Abstracts 2011

January 2011

27.01.11 (Thursday)
16:15, ESO Auditorium, Munich Joint Astronomy Colloquium
"Radiation feedback in high and low mass star and planet formation"
Barbara Ercolano (Cluster/TUM/LMU)
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February 2011

17.02.11 (Thursday)
16:15, ESO Auditorium, Munich Joint Astronomy Colloquium
"Planck's early results on Sunyaev-Zel'dovich clusters"
Nabila Aghanim (IAS, Orsay)
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March 2011

31.03.11 (Thursday)
16:15, ESO Auditorium, Munich Joint Astronomy Colloquium
"Solar magnetism: complexity, simplicity, and a bad conscience"
Manfred Schuessler (MPI f. Sonnenforschung)
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April 2011

18.04.11 (Monday)
15:30, MPA Lecture Hall, Institute Seminar
"Stellar Spectroscopy Unleashed - ELTs and Red Supergiants in the Coma Cluster"
Rolf Peter Kudritzki (Hawaii / currently at MPA)
19.04.11 (Tuesday)
10:00, ESO room D30, Star and Planet Formation Seminar
"Feedback from high-mass stars"
James Dale (USM)
20.04.11 (Wednesday)
13:30, Uni-Sternwarte, room E08, Scheinerstr.1, Munich, USM Seminar
"Subaru weak lensing study of X-ray luminous clusters"
Masahiro Takada (IPMU, Univ. Tokyo)
21.04.11 (Thursday)
10:00, Cluster building, seminar room basement, Special Cluster Talk
"Cosmological constraints on neutrino masses"
Masahiro Takada (IPMU Tokyo, Cluster guest)

May 2011

02.05.11 (Monday)
11:00, MPE Room 1.1.18b, Special MPE Seminar
"Phase referencing and astrometry with the Keck Interferometer"
Julien Woillez (Keck Observatory)
15:30, MPA Lecture Hall, Institute Seminar
"HI properties of massive galaxies - Quenching Mechanism"
Silvia Fabello (MPA)
03.05.11 (Tuesday)
10:00, ESO room D30, Star and Planet Formation Seminar
"What the spatial distribution of stars can tell us about star formation"
Eli Bressert (ESO)
04.05.11 (Wednesday)
13:30, Uni-Sternwarte, room E08, Scheinerstr.1, Munich, USM Seminar
"Reconstructing the Arches cluster"
Stefan Harfst (TU Berlin)
05.05.11 (Thursday)
12:30, ESO Auditorium, Astronomy Talk for Non-Astronomers
"Galaxies II: A Fork, a Trident and a Comb: the Hubble Sequence of Galaxies"
Davor Krajnovic (ESO)
16:15, ESO Auditorium, Munich Joint Astronomy Colloquium
"Intermediate-mass black holes"
Markus Kissler-Patig (ESO)
06.05.11 (Friday)
09:00, IPP D2 Lecture Hall, IPP Kolloquium
"A 100% renewable power system in Europe"
M. Greiner (Aarhus School)
11:00, MPA Lecture Hall, High Energy at MPA
"Galaxy mergers and black hole binaries"
Alessia Gualandris (MPA)
17.05.11 (Tuesday)
10:00, ESO room D30, Star and Planet Formation Seminar
"Characterising sources with disks from the Herschel GASPS survey"
Suzie Ramsay (ESO)
12:30, ESO room D29, Lunch Talk
"Recent PRIMA Commissioning Results"
Gerard van Belle (ESO)
16:30, Cluster building, seminar room, basement, Universe Cluster Colloquium
"Direct Dark Matter Search with CRESST and EURECA"
Jean-Come Lanfranchi (TUM)
19.05.11 (Thursday)
16:15, ESO Auditorium, Munich Joint Astronomy Colloquium
"Stars: The End"
Albert Zijlstra (Jodrell Bank)
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"Stars: The End"
Albert Zijlstra (Jodrell Bank)

Abstract Planetary nebulae reflect the death throes of Sun-like stars. During their final phase of nuclear burning, between 20% and 80% of the mass of the star is ejected through a 'super'-wind. The ejection processdetermines the white dwarf mass distribution, and is the origin of up to half of the gas and dust in the ISM. The cause, evolution and composition of this catastrophic mass loss is still a matter of debate. Observations of planetary nebulae and their progeny, AGB stars, provide important constraints on the superwind and its origin. This talk will discuss mass loss in RGB and AGB stars, including the fate of iron, the formation process of PAHs, and the formation and destruction of dust disks. Observations of planetary nebulae in the Galactic Bulge provide surprising results on the binary stellar population of the Galactic Bulge.
20.05.11 (Friday)
12:30, ESO room D29, Lunch Talk
"Imaging Young Planets at Solar-System Scales"
Mike Ireland (Macquarie University, Sydney, Australia)
24.05.11 (Tuesday)
10:00, ESO Auditorium, Special Talk
"Astrocomb Technology"
Franz X. Kaertner (Center for Free-Electron Laser Science, DESY; and Massachusetts Institute of Technology)
12:30, ESO room D29, Lunch Talk
"A Survey of Stellar Tidal Streams in Nearby Spiral Galaxies"
David Martinez-Delgado (MPIA, Heidelberg)
25.05.11 (Wednesday)
11:00, ESO Auditorium, Special Talk
"Colour computer vision: fundamentals, applications and challenges"
Ignacio Molina Conde (ESO and University of Malaga, Spain)
26.05.11 (Thursday)
16:15, ESO Auditorium, Munich Joint Astronomy Colloquium
"Measuring Black Hole Spin"
Ramesh Narayan (CfA, Harvard)
31.05.11 (Tuesday)
10:00, ESO room D30, Star and Planet Formation Seminar
"Chinese astronomy and understanding RV precision"
Fei Zhao (ESO)
12:30, ESO room D29, Lunch Talk
"Interferometric observations of solar system minor bodies: results and future challenges"
Marco Delbo (CNRS - Observatoire de la Cote d'Azur)
Abstract
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"Chinese astronomy and understanding RV precision"
Marco Delbo (CNRS - Observatoire de la Cote d'Azur)

Abstract I will present results of the first long-baseline interferometric observations of asteroids from the ground. In particular, I will describe the analysis of observations of asteroids that we have obtained with the MIDI instruments of the Very Large Telescope Interferometer (VLTI) of the European Southern Observatory.

I will also discuss some of the current limitations of this technique and how we hope to overcome them using the second-generation instruments of the VLTI. I will show how these latter technological advances in high spatial resolution astronomy will offer a unique opportunity to study the densities and internal structures of asteroids in unprecedented detail.
16:00, Cluster building, seminar room, basement, Special Cluster Talk
"Gamma-ray burst explosions from the first generation of stars"
Rafael de Souza (IPMU Tokyo University)

June 2011

01.06.11 (Wednesday)
12:30, ESO Auditorium, Astronomy Talk for Non-Astronomers
"Galaxies - with small telescopes?"
David Martinez Delgado (MPIA, Heidelberg)
Abstract
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"Galaxies - with small telescopes?"
David Martinez Delgado (MPIA, Heidelberg)

Abstract
Stellar tidal streams are one of the most spectacular phenomena in galaxy formation. These structures form during the gravitational destruction of dwarf galaxies that orbit a spiral galaxy, leaving a spectacular river of stars next to their host galaxy.Spiral galaxies similar to our Milky Way may have swallowed hundreds of satellite galaxies. These defunct satellites should be detectable today as stellar streams, shells or clouds of stars in the outskirts of spirals. Unfortunately, this debris is very faint and thus difficult to observe directly.I will present results of our seach for tidal streams, using a network of small robotic amateur telescopes. Our deep images show for the first time a large variety of giant structures in the outer regions of galaxies. This offers a unique opportunity to study the last stages of galaxy formation, as predicted by cosmological models.
06.06.11 (Monday)
15:30, ESO Auditorium, Special Talk
"The universe as a boundary condition for human life - the energy and information budget of planet Earth: life, climate perceptual space and the future"
Tor Noerretranders (Adjunct professor of the philosophy of science, Copenhagen Business School)
Abstract
07.06.11 (Tuesday)
12:30, ESO room D29, Lunch Talk
"VLBI of interstellar masers to study massive star-formation:the case of the high-mass (proto)star IRAS 20126+4104"
Luca Moscadelli (Arcetri Observatory, Florence)
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"VLBI of interstellar masers to study massive star-formation:the case of the high-mass (proto)star IRAS 20126+4104"

Luca Moscadelli (Arcetri Observatory, Florence)

Abstract

The study of the processes of massive star-formation presents severaltheoretical and observational problems. Since high-mass (proto)stars ignitestill accreting, models of massive star-formation have to deal with the intense stellar radiation, which could push outward and ionize the surrounding gas, reversing the infall and halting the mass accretion.As for the low-mass star formation case, the presence of a disk+outflow systemmight be fundamental to drive the mass accretion even after the star ignites,by channeling stellar photons along the outflow direction and lowering theradiation pression, and by focusing the mass accretion across the disk plane.

Strong molecular masers (as those of the water and methanolcm-wavelengh transitions) are commonly found in regions of massive star-formation and their high brightness temperature makes them suitable targetsfor Very Long Baseline Interferometry (VLBI) observations, which achieve angular resolutions of the order of 1 mas. Multi-epoch VLBI obserations allowus to measure proper motions of maser spots and to derive the 3D velocity fieldof the gas surrounding the (proto)star.

This talk presents the results of multi-epoch VLBI observations of the6.7 GHz methanol and 22.2 GHz water masers towards the source IRAS 20126+4104,one the best candidate of an high-mass (proto)star surrounded by an accretiondisk. From the parallax of the water masers, we obtain a source distance of1.64 +- 0.05 kpc, confirming that this source is an high-mass (proto)star.From the methanol masers we derive the component in the plane of the skyof the systemic velocity of the disk+star system. Accurate knowledge of thedistance and systemic velocity allow us to derive accurate 3D velocitiesof the water masers with respect to the star, and, by fitting the watermaser velocity field with a model, to explore the main properties of thecollimated jet traced by the masers at close distance from the (proto)star.
09.06.11 (Thursday)
12:30, ESO Council Room, Astronomy Talk for Non-Astronomers
"Interferometry 101: Measuring the Temperatures and Radii of Stars or: How I Learned to Stop Worrying and Love Fringes"
Gerard van Belle (ESO)
Abstract
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"Interferometry 101: Measuring the Temperatures and Radii of Stars or: How I Learned to Stop Worrying and Love Fringes"

Gerard van Belle (ESO)

Abstract

One of the most straightforward things an array of telescopes, or 'interferometer', can do is measure the sizes of stars. Such measurements allow us to directly establish the basic properties of these building blocks of the universe around us - their sizes, and their temperatures.Gerard aims to describe the mystical principles underlying a func- tional stellar interferometer, in a way that is understandable to the lay person - or at least, no more confusing than it is to astronomers.
16:15, MPE Large Seminar Room 1.1.18b, Munich Joint Astronomy Colloquium
"The Turbulent-Fragmentation Model of Star Formation"
Paolo Padoan (ICREA - ICC, University of Barcelona)
Abstract
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"The Turbulent-Fragmentation Model of Star Formation"

Paolo Padoan (ICREA - ICC, University of Barcelona)

Abstract

The turbulent nature of the interstellar medium can be viewed as an opportunity to model the global outcome of the star formation process, namely the star formation rate and the stellar initial mass function.I will discuss the observational evidence for the nature and the effect of supersonic turbulence in molecular clouds. I will then present a simple model for the star formation rate and the stellar initial mass function, based on known statistical properties of the turbulence. Model assumptions are based on high resolution simulations, which are themselves tested by a direct comparison with observations.
14.06.11 (Tuesday)
10:00, ESO room D30, Star and Planet Formation Seminar
"Investigating the early formation of planetary systems through mm-wave interferometry"
Luca Ricci (ESO)
12:30, ESO room D29, Lunch Talk
"Colour gradient in early-type galaxies at high-z"
Adriana Gargiulo (INAF - Osservatorio Astronomico di Brera)
Abstract
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"Colour gradient in early-type galaxies at high-z"

Adriana Gargiulo (INAF - Osservatorio Astronomico di Brera)

Abstract

I present F606W - F850LP (~UV - U restframe) and F850LP - F160W (~(U - R restframe) color gradients for two samples of early type galaxies (ETGs) at 1<z_spec<2. Our samples have been selected from GOODS-Southfield and each one of them includes both normal ETGs having effective radii comparable to the mean radius of local ones and compact ETGs with effective radii from two to six times smaller. Colour gradients in the F606W - F850LP bands have been derived taking advantage of the ultradeep HST /ACS observations covering the GOODS field which provide a spatial resolution of about 0.8 kpc at the redshift of the galaxies, while colour gradients in the F850LP - F160W bands exploit the capability of the WFC3 images. Despite the narrow wavelength baseline covered (1000 A) by the two filters F606W and F850LP, which sample approximately the emission dominated by the same stellar population, we detect significant gradients, both positive and negative, in 50 percent of our sample. On the contrary, the analysis of the F850LP and F160W bands shows high-z ETGs to preferentially have negative color gradients, with stellar populations much redder in the centers than in the outskirts. These first estimates of color gradients of high-z ETGs represent a fundamental stone to constrain the model of galaxy formation and evolution.
16.06.11 (Thursday)
16:15, ESO Auditorium, Munich Joint Astronomy Colloquium
"Achievements and challenges in star formation"
Richard de Grijs (Peking University)
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"Achievements and challenges in star formation"
Richard de Grijs (Peking University)

Abstract What has been the most profound discovery, progress or idea that has emerged in astronomy over the last decade? And what will be the most important challenge in astronomical research in the next decade? These questions are at the heart of our discipline, but we rarely venture outside of our own niche areas. I will attempt to focus on the broad picture underlying the field of star formation and discuss the requisite conditions for sustained progress in this field, aided by recent achievements in the context of my group's star cluster research.
21.06.11 (Tuesday)
12:30, ESO room D29, Lunch Talk
"The Nature of Broad Absorption Line Quasars"
Michael Di Pompeo (University of Wyoming)
Abstract
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"The Nature of Broad Absorptiom Line Quasars"

Michael Di Pompeo (University of Wyoming)

Abstract

The subclass of quasars containing broad absorption lines (BALs), the observational signature of high velocity outflows, has been known about for decades. However, while much work has been done their true nature has remained elusive. In order to fully understand and model quasars and their role in galaxy evolution a proper understanding of these massive outflows is necessary. As my PhD thesis I have been working on a study of a large sample of BAL quasars using radio observations and spectropolarimetry, two of the most important tools in distinguishing between competing models for these important objects. In this talk I will discuss the project and preliminary results so far.
22.06.11 (Wednesday)
10:30, ESO Auditorium, Special Talk
"Gratings for high performance applications fabricated by e-beam lithography"
Uwe Zeitner (Fraunhofer Institute for Applied Optics and Precision Engineering IOF, Jena)
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"Gratings for high performance applications fabricated by e-beam lithography"

Uwe Zeitner (Fraunhofer Institute for Applied Optics and Precision Engineering IOF, Jena)

Abstract

Gratings are essential components in different high performance optical set-ups such as the spectrometers in space missions or ultra-short-pulse laser compression arrangements. In a lot of cases these two rather distinct applications do have a number of common aspects from the grating point of view. Often both require gratings operating close to the technological accessible limits of today's fabrication technology. Critical parameters are the diffraction efficiency and its polarization dependency, the wave-front error introduced by the grating, and stray-light performance. Space applications have specific environmental requirements and the laser application typically requires a high damage threshold. All these properties need to be controlled precisely on sometimes rather large grating areas. Gratings with extensions of up to 200mm or above are not unusual.

The talk gives an overview on how such high performance gratings can be realized by electron-beam lithography. This approach is demonstrated by different examples. One of them is the design and fabrication of the grating for the Radial-Velocity-Spectrometer of the GAIA-mission of the ESA.
28.06.11 (Tuesday)
10:00, ESO room D30, Star and Planet Formation Seminar
"New Links in the Asteroid-Meteorite Connection"
Richard P. Binzel (MIT)
12:30, ESO room D29, Lunch Talk
"Dust Around Compact Objects - Clues from the Invisible Monster"
Don Hoard (Spitzer Science Center, California Institute of Technology)
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"Dust Around Compact Objects - Clues from the Invisible Monster"

Don Hoard (Spitzer Science Center, California Institute of Technology)

Abstract

Recent infrared observations, particularly from the Spitzer SpaceTelescope, of white dwarfs, cataclysmic variables and otherinteracting compact binaries, have revealed the presence of dust inmany systems. I have recently made a thorough investigation of theunique and enigmatic long-period (27.1 year) eclipsing binary starEpsilon Aurigae. This system started its latest 2-year long eclipsein August 2009. I utilized new and archival observations from the farultraviolet to the mid-infrared to resolve the nearly 200 year oldmystery concerning the nature of the stellar components in thissystem. Along the way, I have also made some discoveries about thenature of the solar system size dust disk in Epsilon Aurigae that showit to be similar, in all but scale, to the dust disks around compactobjects. I will discuss the properties of dust in Epsilon Aurigae andcompact binaries, and examine similarities and differences that canreveal new insights into the structure, formation, and evolution ofthese two types of binaries, that span the range of known orbitalperiods from the longest to the shortest.
16:30, Cluster Building, seminar room, basement, Universe Cluster Colloquium
"New Physics Searches with Rare Decays"
Christoph Bobeth (TUM)

 


July 2011

05.07.11 (Tuesday)
12:30, ESO room D29, Lunch Talk
"The influence of dust on velocity dispersion observations of early-type galaxies in the Fornax cluster"
Joachim Vanderbeke (ESO Chile)
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"The influence of dust on velocity dispersion observations of early-type galaxies in the Fornax cluster"

Joachim Vanderbeke (ESO Chile)

Abstract

We have carried out a systematic, homogeneous comparison of optical and near-infrared dispersions. Our magnitude-limited sample of early-type galaxies in the Fornax cluster comprises 11 elliptical and 11 lenticular galaxies. We were able to determine the central dispersions based on the near-infrared CO absorption band head for 19 of those galaxies. The velocity dispersions range from less than 70 km/s to over 400 km/s. We compare our near-infrared velocity dispersions to the optical dispersions measured by Kuntschner (2000). Contrary to previous studies, we find a one-to-one correspondence with a median fractional difference of 6.4 per cent. We examine the correlation between the relative dust mass and the fractional difference of the velocity dispersions, but find no significant trend. Our results suggest that early-type galaxies are largely optically thin, which is consistent with recent Herschel observations.
16:30, Cluster Building, seminar room, basement, Universe Cluster Colloquium
"Inclusive semileptonic B decays"
Paolo Gambino (University of Turin)
08.07.11 (Friday)
12:30, ESO room D29, Lunch Talk
"Star and Planet Formation in Extreme Conditions: Life in Cygnus OB2"
Nick Wright (Harvard-Smithsonian Center for Astrophysics)
Abstract
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"Star and Planet Formation in Extreme Conditions: Life in Cygnus OB2"

Nick Wright (Harvard-Smithsonian Center for Astrophysics)

Abstract

Cygnus OB2 is the most massive young stellar association within 2kpc, containing at least 65 O-type stars and a total mass of ~30,000 Msun. Its proximity provides a unique glimpse into star formation at the largest of scales: the extreme physical conditions induced by the proximity of thousands of massive stars, and the large spatial scales under which the star formation process takes place. It represents a vital stepping stone between studies of nearby regions such as Orion and the distant super-star clusters that dominate starburst galaxies.

I will present results from the recent Chandra Legacy Survey of Cygnus OB2, which has produced a catalog of ~10,000 young stars with well-defined completeness limits. Results from these and other multi-wavelength observations are helping us understand how the fundamental products of star formation vary in these massive regions. I will also discuss a follow-up radial velocity survey of the association that will not only reveal the current dynamical state of the association, but also probe the formation and eventual dissolution of such massive star forming regions.
12.07.11 (Tuesday)
10:00, ESO room D30, Star and Planet Formation Seminar
"Protoplanetary Disks: Progress and Prospects with Millimeter Interferometry"
David Wilner (Harvard Smithsonian CfA)
12:30, ESO room D29, Lunch Talk
"SUBARU near-infrared observations and numerical simulations of protoplanetary disks in a young multiple star"
Satoshi Mayama (National Astronomical Observatory of Japan)
Abstract
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"SUBARU near-infrared observations and numerical simulations of protoplanetary disks in a young multiple star"

Satoshi Mayama (National Astronomical Observatory of Japan)

Abstract

Protoplanetary disks are ubiquitously observed around young solar-mass stars and are considered to be not only natural by-products of stellar evolution but also precursors of planet formation. If a forming star has close companions, the protoplanetary disk may be seriously influenced. It is important to consider this effect because most stars form as multiples. Thus studies of protoplanetary disks in multiple systems are essential to describe the general processes of star and planet formation.

At lunch talk, we show the first direct image of an interacting binary protoplanetary disk, showing circumprimary and circumsecondary disks resolved with a 0.1 arcsecond resolution. The binary system exhibits a bridge of infrared emission connecting the two disks and a long spiral arm extending from the circumprimary disk. Numerical simulations reveal that the bridge corresponds to gas flow and a shock wave caused by the collision of gas rotating around the primary and secondary stars. The simulations also show that fresh material streams along the spiral arm, confirming the theoretical proposal that gas is replenished from a circummultiple reservoir. These results reveal the mechanism of interacting protoplanetary disks in young multiple systems. Furthermore, our observations provide the first direct image that enables a comparison with theoretical models of mass accretion in binary systems. The observations of this binary system provide a great opportunity to test and refine theoretical models of star and planet formation in binary systems.
16:30, Cluster Building (basement), Universe Cluster Colloquium
"Classical Dimensional Transmutation and Confinement"
Viatcheslav Mukhanov (LMU)
13.07.11 (Wednesday)
11:00, Cluster Building (basement), Special Universe Cluster Talk
"Observational evidence of a hypernova in our Galaxy"
Anatoli Iyudin (Moscow State University)
14.07.11 (Thursday)
13:30, Cluster Building (basement), Special Universe Cluster Talk
"Multi-phase gaseous galaxy halos"
Ralph Tuellmann (CfA Harvard)
19.07.11 (Tuesday)
12:30, ESO room D29, Lunch Talk
"An X-Shooter survey of nearby star forming regions: low and sub-stellar mass objects"
Juan Manuel Alcala (Osservatorio Astronomico di Capodimonte, Naples)
Abstract
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"An X-Shooter survey of nearby star forming regions: low and sub-stellar mass objects"

Juan Manuel Alcala (Osservatorio Astronomico di Capodimonte, Naples)

Abstract

First results of an X-Shooter@VLT survey of the nearby star-forming regions in Lupus, sigma Ori and TW Hya are presented. This survey allows a detailed characterization of the Young Stellar and sub-stellar Objects(YSOs), and provides a database of accretion diagnostics from the Br-gamma and Pa-beta lines in the near-IR to the Balmer jump in the UV (detected even in some brown dwarfs), including the full optical band with the Balmer series and He 5876 and the Ca IRT. A major topic of this project is studying empirical relations between each of these accretion diagnostics and the mass accretion rate. Eventually, this enables the investigation of the scatter in the mass accretion rate vs. mass diagram, and to constrain formation and early evolutionary scenarios of low-mass YSOs and BDs. Several of our targets drive outflows that are traced by forbidden lines. The ratio between outflow and accretion rate is an important ingredient of jet launching models, and can be constrained here for very low-mass objects. In short, the enormous wavelength range of X-Shooter yields the opportunity for a comprehensive study of accretion and outflows through simultaneous observations of all diagnostics, eliminating variability-induced uncertainties.
21.07.11 (Thursday)
10:00, ESO room D30, Star and Planet Formation Seminar
"Disk mass evolution and the growth of planetesimals"
Jonathan Williams (IfA, Hawaii)
12:30, ESO room D29, Lunch Talk
"Do the Fundamental Constants change with Time?"
Nissim Kanekar (National Centre for Radio Astrophysics, India)
Abstract
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"Do the Fundamental Constants change with Time?"

Nissim Kanekar (National Centre for Radio Astrophysics, India)

Abstract

Radio spectroscopy in the multiple redshifted OH 18cm lines provides a powerful probe of changes in the fine structure constant alpha, the proton g-factor g_p and the proton-electron mass ratio m_p/m_e. Under certain astrophysical conditions, a maser mechanism causes the satellite OH 18cm lines to be "conjugate", with one line in absorption, the other in emission and the sum of the optical depths consistent with noise. This implies that the lines arise in precisely the same gas, making them ideal transitions through which to study changes in alpha, mu and g_p, with few systematic effects. In this talk, I will present results from deep WSRT and Arecibo studies of a redshifted conjugate satellite OH system, at z ~ 0.25 towards PKS 1413+135. I will also describe results from an alternative radio technique, comparing redshifts of inversion and rotational transitions, that has yielded the best sensitivity today to changes in the proton-electron mass ratio.
13:00, Cluster Building (basement), Special Universe Cluster Talk
"Probing the very early Universe with large-scale structure"
Fabian Schmidt (CalTech)
22.07.11 (Friday)
11:00, Cluster building, seminar room (basement), Universe Cluster Talk
"Dynamical behavior of neutrons in the early universe"
Martin Fuerst (USM)
25.07.11 (Monday)
11:00, Universe Cluster building (basement), Special Cluster Talk
"Coevolution of dust and turbulence in protoplanetary disks"
Satoshi Okuzumi (Nagoya University, Japan)
26.07.11 (Tuesday)
10:00, ESO room D30, Star and Planet Formation Seminar
"Planets: minor detail or key driver of proto-stellar disc evolution?"
Sergei Nayakshin (Leicester University)
12:30, ESO room D29, Lunch Talk
"The South African Square Kilometre Array Precursor MeerKAT"
Erwin de Blok (University of Cape Town)
Abstract
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"The South African Square Kilometre Array Precursor MeerKAT"

Erwin de Blok (University of Cape Town)

Abstract

I will describe the South African SKA Precursor MeerKAT, a 64 x 13.5 meter Gregorian offset dish radio interferometer, soon to start construction in the South African Karoo desert.

A proto-type for MeerKAT, called KAT-7, is now undergoing commissioning and I will show some of the first results. The first 5 years of MeerKAT's operational life will be dedicated to a number of large Legacy surveys, and I will give a short overview of the planned science.
16:30, Universe Cluster building (basement), Universe Cluster Colloquium
"Three heterodox aspects of the structure of matter at a neutron star"
Felipe J. Llanes Estrada (Univ. Complutense de Madrid)
28.07.11 (Thursday)
12:30, ESO room D29, ALMA Talk
"Basics of Imaging and Deconvolution in Radio Interferometry"
David Wilner (Harvard-Smithsonian CfA)

August 2011

09.08.11 (Tuesday)
10:00, ESO room D30, Star and Planet Formation Seminar
"Characterizing Early Stages of Massive, Clustered Star Formation in Infrared Dark Clouds"
Ke Wang (Peking University)
18.08.11 (Thursday)
12:30, ESO room D29, Lunch Talk
"Atomic Spectroscopy at NIST for Astrophysical Applications"
Gillian Nave (National Institute of Standards and Technology - NIST, Gaithersburg, MD, USA)
Abstract
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"Atomic Spectroscopy at NIST for Astrophysical Applications"

Gillian Nave (National Institute of Standards and Technology - NIST, Gaithersburg, MD, USA)

Abstract

I shall give a brief overview of the Atomic Spectroscopy Group at NIST,including its work in high-resolution spectroscopy, the Electron BeamIon Trap, and the Atomic Spectroscopy databases. I shall summarize someof our work on reference wavelengths for the calibration of astronomicalspectrographs, and finish by presenting the work we are doing on thespectra and energy levels of Fe II and Cr II.
23.08.11 (Tuesday)
10:00, ESO room D30, Star and Planet Formation Seminar
"Linear regression and the extinction law"
Joana Ascenso (ESO)
Abstract
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"Linear regression and the extinction law"

Joana Ascenso (ESO)

Abstract

Linear regression is probably the most widely used tool in science, but it is surprisingly biased under some conditions and cannot be applied to all problems. This becomes clear when deriving the extinction law from photometric data, when the problem of linear regression must be applied to data with errors in both coordinates, errors that are correlated, and with intrinsic scatter. Using an unbiased method that we developed and validated, we determine the extinction law for two dense cores of the Pipe Nebula, showing that the dust grains are larger at high densities when compared to the ISM, and that the grains likely evolve with the onset of star formation.
25.08.11 (Thursday)
12:30, ESO room D29, Lunch Talk
"Supershells as Molecular Cloud Factories in the Evolving ISM"
Joanne Dawson (University of Tasmania)
Abstract
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"Supershells as Molecular Cloud Factories in the Evolving ISM"

Joanne Dawson (University of Tasmania)

Abstract

The last decade has seen the development of a new paradigm for molecular cloud formation, in which the compression, cooling and fragmentation of the atomic medium in large-scale colliding flows drives the formation of turbulent, star-forming molecular gas. Within the scope of physical systems covered by this theory are supershells – large loops, shells and cavities formed by the cumulative stellar feedback from OB clusters, which shape the ISM on scales of 100s of parsecs. I will report the results of CO(J=1-0) and HI 21cm line observations of the molecular and atomic ISM in two Galactic supershells, in order to examine both qualitatively and quantitatively the role they play in the formation, evolution, transport, disruption of molecular gas. Our observations image the ISM to resolutions of ~ 2pc (~2.5') over ~100 deg2 fields, revealing rich substructure in both tracers, and walls that are dominated by cold HI. A key result of this work is the measurement of an enhanced level of molecularization over the volumes of both objects, providing the first direct observational evidence of increased molecular cloud production due to the influence of supershells, and demonstrating that in the case of these two objects the global influence on the molecular ISM is a positive one. However, our observations also highlight another long-recognised fact – that the influence of shells may also be disruptive to molecular gas on local scales; driving the atomic-molecular transition in the opposite direction in pre-existing clouds disrupted by the shell’s passage.

I will also briefly introduce GASKAP, an upcoming high spatial/spectral resolution survey of HI and OH in the Galaxy and Magellanic clouds. GASKAP's core aims are targeted on broad questions of ISM evolution and Galactic structure, and the physics and dynamics of the matter within our local Galactic system.
30.08.11 (Tuesday)
12:30, ESO room D29, Lunch Talk
"Brewing Great Science with MALT90"
Jill Rathborne (CSIRO Astronomy and Space Science, Australia)
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"Brewing Great Science with MALT90"

Jill Rathborne (CSIRO Astronomy and Space Science, Australia)

Abstract

The Millimetre Astronomy Legacy Team 90 GHz (MALT90) survey is a new, international project aimed at characterizing the physical and chemical evolution of high-mass star-forming cores. Exploiting the unique broad frequency range and fast-mapping capabilities of the Mopra 22-m Telescope, MALT90 will obtain 3′×3′ maps toward ~3000 point sources identified in the ATLASGAL 870 μm galactic plane survey. Because we can map 16 lines simultaneously with excellent spatial (38′′) and spectral (0.11km s−1) resolution, the data reveal a wealth of information about source morphologies, chemistry, and kinematics. In this talk I will outline the survey strategy, current status, showcase some early results, and discuss several exciting follow-up projects we have planned with ALMA.

September 2011

05.09.11 (Monday)
12:30, ESO room D29, Lunch Talk
"Adventures in Planet Formation"
Chris Ormel (Max Planck Institute for Astronomy, Heidelberg)
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"Adventures in Planet Formation"

Chris Ormel (Max Planck Institute for Astronomy, Heidelberg)

Abstract

In the core accretion paradigm of planet formation, bodies grow large by sweeping up smaller bodies. The process is traditionally distinguished into two phases: i) the formation of planetesimals bodies out of a reservoir of primordial dust driven by contact (molecular) forces; and ii) the accretion of these planetesimals to protoplanets under their mutual gravitational attraction. After briefly addressing recent models regarding dust collisions in the pre-planetesimal phase, I will review the planetesimal accretion stage. Here gravitational focusing accelerates growth. Initially, growth proceeds in a runaway fashion (one body outpaces the rest in terms of mass) but, due to feedback effects in the form of dynamical stirring, passes into the much slower oligarchic growth phase thereafter. Using a new simulation method, I will present a new condition for the transition between runaway and oligarchic growth. Next, I will address the question how the emergent protoplanets do acquire their final solid mass: by sweepup of big planetesimal bodies or in a more convoluted setting that involves accretion of small particles.
06.09.11 (Tuesday)
10:00, ESO room D30, Star and Planet Formation Seminar
"Structure and variability of the planet-forming regions in the disc around HD100546 probed with VLTI/MIDI"
Olja Panic (ESO)
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"Structure and variability of the planet-forming regions in the disc around HD100546 probed with VLTI/MIDI"

Olja Panic (ESO)

Abstract

I will discuss the advantages and challenges of the modelling of mid-infrared interferometric observations of circumstellar discs. In particular, I present VLTI observations of a bright Herbig Be star, HD100546. Many signs suggest that this disc hosts one or more planets, namely a gas and dust gap, spiral structure seen in scattered light imaging, Hale-Bopp-like mineralogy. Our mid-infrared interferometric VLTI/MIDI observations probe the disc brightness distribution in the regions from 0.2 to about 20AU where the putative planets may open gaps and cause resonant clumping of disc material. Our data show the presence of disc material both close to the dust sublimation radius (consistent with prior VLTI/AMBER data) and beyond the outer edge of the disc gap, located at about 13~AU (also revealed with VLT/CRIRES and NACO instruments). We detect up to 50% variability in the correlated interferometric fluxes, and their shapes, measured on identical 40m baselines one year apart. This variability can be explained either by changes in the thickness and location of the inner rim, changes in the dust properties at the rim, or by disc asymmetry in the inner few AU. The observed flux changes are too subtle to be detected with a single UT telescope (a few percent of the total disc flux), stressing the need for interferometric monitoring.
12:30, ESO room D29, Lunch Talk
"Characterizing Precursors to Stellar Clusters with Herschel"
Cara Battersby (Center for Astrophysics and Space Astronomy, University of Colorado, Boulder)
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"Characterizing Precursors to Stellar Clusters with Herschel"

Cara Battersby (Center for Astrophysics and Space Astronomy, University of Colorado, Boulder)

Abstract

Massive stars and stellar clusters play a dominant role in shaping the Universe around us, yet their formation mechanism remains poorly understood. In this talk, I present results from the Herschel Infrared Galactic Plane Survey (Hi-GAL) and demonstrate how Hi-GAL can be used to identify potential proto-clusters throughout the Galaxy and help us learn more about the formation processes of stellar clusters and the massive stars that form within them. I present temperature and column density maps in the l=30 and l=59 degree Hi-GAL fields. Using these maps, I compare the physical properties of Infrared Dark Clouds (IRDCs; condensations so cold and dense that they obscure the bright Galactic mid-IR background - thought to be precursors to stellar clusters) to other dust continuum sources. I characterize the level of star formation activity in both populations of sources as well as how it correlates with temperature and column density, giving us some indication as to how these sources evolve.
13.09.11 (Tuesday)
12:30, ESO room D29, Lunch Talk
"10 years of observing with an AO secondary - lessons learned"
Morag Hastie (MMT Observatory)
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"10 years of observing with an AO secondary - lessons learned"

Morag Hastie (MMT Observatory)

Abstract

It has been known for over 20 years that using a deformable secondary mirror in a telescope to correct for atmospheric distortions has several advantages for scientific gain over conventional, bench-mounted, adaptive optic (AO) systems. Conventional AO systems increase the number of reflective surfaces into the telescope beam, which limits the capabilities of the system and the resultant image quality. However, until very recently, only one observatory in the world has had a working AO secondary in operation. The MMT Observatory in Arizona commissioned an AO secondary mirror in late 2002 and has worked in the intervening years to shepherd a proto-type technology into a facility class system. The AO secondary is now routinely used for science operations upwards of 60 nights every year with both the NGS and LGS systems. In the light of the increased use of AO secondaries at current (e.g. MMT, LBT, VLT) and proposed facilities (e.g GMT), it is timely for us to talk about the lessons that have been learned by the MMT observatory over the last 10 years. In my talk I will give an overview of the MMT's AO secondary but will concentrate on describing how the system performs, the improvements we are putting in place to increase performance and the operational "pot holes" which we have encountered over the years.
15.09.11 (Thursday)
16:15, ESO Auditorium, Munich Joint Astronomy Colloquium
"Massive stars: From the VLT to the ELTs"
Chris Evans (Royal Observatory Edinburgh)
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"Massive stars: From the VLT to the ELTs"

Chris Evans (Royal Observatory Edinburgh)

Abstract

Massive stars play a key role in the dynamical and chemical evolution of star-forming galaxies, via their intense stellar winds, UV radiation fields, and explosive deaths. To develop realistic tools to analyse integrated-light observations of distant galaxies, we first need to calibrate the models via study of stars closer to home. To this end, I will present first results from the VLT-FLAMES Tarantula Survey, which has obtained multi-epoch spectroscopy of the massive-star population of 30 Doradus, the richest stellar nursery in the Local Group. Looking ahead, I will also discuss the exciting potential of the future Extremely Large Telescopes (ELTs), which will enable direct abundance estimates for individual stars in galaxies across a large volume of the local Universe.
20.09.11 (Tuesday)
10:00, ESO room D30, Star and Planet Formation Seminar
"The Variable Young Stellar Object Survey (VYSOS) in Hawaii"
Bo Reipurth (Institute for Astronomy, University of Hawaii)
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"The Variable Young Stellar Object Survey (VYSOS) in Hawaii"

Bo Reipurth (Institute for Astronomy, University of Hawaii)

Abstract

Young stars show a wide range of photometric variability. The most common cause is accretion, ranging from the typical small-scale flickering to the major but rare FU Orionis type eruptions. Other variability is due to huge star spots, which dominate mostly at later evolutionary stages. And a small number of pre-main sequence binaries are now adding important information about the absolute dimensions of young stars. Major sky surveys now hold promise that the variability of young stars can be properly monitored and studied. However, almost all of these surveys employ cadences which are not very useful for the study of young stars, and their saturation limits exclude a large fraction of the brighter young stars, which are amenable to further spectroscopic study. To overcome these problems, I have developed the VYSOS survey, which employs two small robotic telescopes at the Mauna Loa Observatory in Hawaii to monitor the principal star forming regions on a nightly basis.
12:30, ESO room D29, Lunch Talk
"Cosmic Evolution in the Australia Telescope Large Area Survey"
Minnie Mao (University of Tasmania)
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"Cosmic Evolution in the Australia Telescope Large Area Survey"

Minnie Mao (University of Tasmania)

Abstract

The Australia Telescope Large Area Survey (ATLAS) observes seven square degrees of sky down to 10 microJanskys at 1.4 GHz using the Australia Telescope Compact Array. The survey covers two fields to minimize cosmic variance; the Chandra Deep Field South (CDFS) and the European Large Area ISO Survey - S1 (ELAIS). My PhD focusses specifically on the cosmic evolution of radio sources in ATLAS. Using spectroscopic redshifts we obtained from the Anglo-Australian Telescope, we have studied the radio luminosity function for ATLAS sources. We have also identified and analysed wide-angle tailed galaxies in ATLAS and discovered a ~12 Mpc large-scale structure in ELAIS at z~0.2. Using deep far-infrared data from the FIDEL project we were able to study the far-infrared radio correlation in the eCDFS and we found no evidence for evolution out to redshifts of ~3.
22.09.11 (Thursday)
16:15, ESO Auditorium, Munich Joint Astronomy Colloquium
"Dark Matter, Dwarf Galaxies, and Massive Failures in the Halo of the Milky Way"
James Bullock (University of California)
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"Dark Matter, Dwarf Galaxies, and Massive Failures in the Halo of the Milky Way"

James Bullock (University of California)

Abstract

The favored dark energy plus cold dark matter (LCDM) model of cosmology predicts that the Milky Way should be surrounded by thousands of dark matter satellite clumps, in great excess of the observed count of Galactic dwarf satellite galaxies. This mismatch is known as the "missing satellite problem". Recent discoveries in theSloan Digital Sky Survey have revealed a new population of ultra-faint dwarf satellites, motivating excitement within the community that some "missing" LCDM satellites are finally being found. Unfortunately for the theory, the situation is not quite so rosy once the dynamical masses of the known satellites are considered. Specifically, the majority of the most massive dark matter satellites predicted to exist are too dense to host any of the bright satellite galaxies of the Milky Way. This poses a serious puzzle theoretically: either galaxy formation becomes effectively stochastic on scales smaller than ~0.1L* or the central densities of dark matter subhalos are significantly lower than predicted in dissipationless simulations. I discuss some possible solutions to this puzzle from the standpoint of baryonic physics and non-standard dark matter physics.
27.09.11 (Tuesday)
12:30, ESO room D29, Lunch Talk
"HOPS: the H2O southern Galactic Plane Survey"
Andrew Walsh (James Cook University, Australia)
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"HOPS: the H2O southern Galactic Plane Survey"

Andrew Walsh (James Cook University, Australia)

Abstract

I will summarise early results of HOPS which has recently completed observations on the Mopra radiotelescope in Australia. HOPS has covered 100 square degrees of the Galactic plane in the 12mm band, including observations of water masers, NH3 inversion transitions, HCCCN, radio recombination and methanol spectral lines. We have found 540 water masers, of which nearly two-thirds are new detections. We also find around 700 NH3 clumps, as well as widespread detections of HCCCN and occasional detections of Class I methanol masers and other spectral lines. It is our intention that the HOPS data base can be used as a map of high density gas in the southern Galaxy, particularly as a finding chart for ALMA.
29.09.11 (Thursday)
16:15, ESO Auditorium, Munich Joint Astronomy Colloquium
"Comets, charge exchange, and a novel look at the X-ray universe"
Konrad Dennerl (MPE)
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"Comets, charge exchange, and a novel look at the X-ray universe"

Konrad Dennerl (MPE)

Abstract

The discovery of cometary X-ray emission in 1996 with ROSAT has revealed the importance of a fundamental process for the generation of X-rays which was overlooked for a long time: charge exchange, a process where X-rays are not produced by hot electrons, but by ions picking up electrons from cold gas. It has also provided a conceptual breakthrough for the understanding of the soft X-ray background, and has opened up entirely new fields of X-ray studies. The talk will attempt to put the various aspects of the study of charge exchange reactions into a broader historical context, with special emphasis on X-ray astrophysics, where cometary X-rays may have stimulated a novel look at our universe.

October 2011

04.10.11 (Tuesday)
10:00, ESO room D30, Star and Planet Formation Seminar
"On the Formation of O-type Stars"
Roberto Galvan-Madrid (ESO)
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"On the Formation of O-type Stars"

Roberto Galvan-Madrid (ESO)

Abstract

The 'truly' massive stars (M > 10 to 20 Msun) likely start to ionize their surroundings before they reach their final mass. How can they accrete in spite of the presence of over-pressurized gas? I will present Submillimeter Array and Very Large Array studies of very luminous (L > 10^5 Lsun) massive star-formation regions in the early stages of ionization: molecular-line observations at resolutions from a few arcsec to 0.3 arcsec reveal rotation, infall, convergence of filamentary structures, and/or outflow from parsec scales down to < 0.05 pc. Small groups of massive (proto)stars are found at different evolutionary stages. The innermost ionized gas sometimes shows organized motions, probably from outflow and/or rotation. Multiepoch observations of the free-free continuum reveal flux variations in timescales of years, attributable to interactions with the surrounding molecular gas. Observations, analytical models, and numerical simulations of HII region evolution in star-forming accretion flows suggest that: i) These very massive stars form in accretion flows that are partially ionized. ii) The cores from which these stars form keep accreting material from their enviroment (clump).
12:30, ESO room D29, Lunch Talk
"The Dynamical Evolution of Newborn Triple Systems"
Bo Reipurth (University of Hawaii)
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"The Dynamical Evolution of Newborn Triple Systems"

Bo Reipurth (University of Hawaii)

Abstract

Recent large surveys have established improved statistics of binarity and multiplicity of embedded low-mass stars, which not only have demonstrated the known excess of binaries among newborn stars, but also have uncovered a surprising excess of wide companions. A new set of extensive numerical N-body simulations of stellar embryos accreting from dense cloud cores have been able to reproduce the main features of the observations, and have uncovered a wide range of dynamical behaviors, which have unexpected connections to various poorly understood phenomena in early stellar evolution, including FUor eruptions and the formation of spectroscopic binaries.
06.10.11 (Thursday)
12:30, ESO room D30, Lunch Talk
"Atmospheric water vapour measurement campaigns for E-ELT site characterization"
Richard Querel (Radioastronomical Instrumentation Group, Department of Electrical Engineering, Universidad de Chile)
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"Atmospheric water vapour measurement campaigns for E-ELT site characterization"

Richard Querel (Radioastronomical Instrumentation Group, Department of Electrical Engineering, Universidad de Chile)

Abstract

In 2009, in the context of E-ELT site characterization, our team conducted a set of dedicated campaigns to measure precipitable water vapour (PWV) over La Silla, Paranal and APEX. The goal of the campaigns was to compare contemporaneous ground-based measurement techniques to radiosonde launches and overhead satellite estimates of PWV. ESO facility instruments provided high resolution telluric absorption/emission spectra at high cadence in parallel with continuous infrared radiometer (IRMA) measurements. A historical analysis of PWV over the sites was also performed by processing archival data. Based in part on the results from these campaigns the E-ELT site selection advisory committee recommended the Armazones site and the VISIR upgrade project is currently deploying a water vapour monitor for permanent operation on Paranal.
06.10.11 (Thursday)
16:15, ESO Auditorium, Munich Joint Astronomy Colloquium
"High redshift ULIRGs and the formation of massive galaxies"
Scott Chapman (Institute of Astronomy, Cambridge, UK)
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"High redshift ULIRGs and the formation of massive galaxies"
Scott Chapman (Institute of Astronomy, Cambridge, UK)

Abstract Studying ultraluminous galaxies (ULIRGs) at early times (z>2) provides insight into the formative phases of massive galaxies around us today. While the field has become a relatively mature science, there remain various aspects of this field that are still mired in uncertainty, and new facilities offer possibilities for great leaps forward in our understanding. I will provide an overview of this exciting field, and present new avenues of research into high-z ULIRGs which are significantly pushing our understanding of the population. These include Herschel-HerMES, the South Pole Telescope (SPT), our recently completed IRAM-PdBI survey of CO 50 high-z SMGs (Bothwell et al. 2011), and the CDFS-LESS survey with LABOCA and its followup.
07.10.11 (Friday)
15:00, Cluster Building Seminar Room, basement, Special Universe Talk
"Indirect search for new physics with the LHCb experiment"
Johannes Albrecht (CERN)
10.10.11 (Monday)
13:30, Cluster Building Seminar Room, basement, Special Universe Talk
"Weighing the Giants: Measuring Unbiased Weak Lensing Masses for X-ray Luminous Galaxy Clusters"
Douglas Applegate (Stanford University)
11.10.11 (Tuesday)
11:00, MPE Seminar Room 1.1.18b, Universe Cluster Seminar
"The Interstellar Medium: confronting 3D high resolution simulations with observations"
Dieter Breitschwerdt (TU Berlin)
13.10.11 (Thursday)
16:15, MPE Seminar Room 1.1.18b, Munich Joint Astronomy Colloquium
"A Holistic Study of Supernovae"
Alicia Soderberg (Harvard University, Cambridge MA)
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"A Holistic Study of Supernovae"

Alicia Soderberg (Harvard University, Cambridge MA)

Abstract

Throughout history, observational supernova studies have focused almost exclusively on their strong optical emission powered by the radioactive decay of Nickel-56. Yet many of the leading breakthroughs in our understanding of supernovae and their progenitors have been enabled by observations at other wavelengths. For example, through the combination of radio, optical, X-ray and gamma-ray observations, we now know that less than 0 .1 percent of all core-collapse supernovae require "central engines" (compact accreting sources) to power associated gamma-ray bursts. As I will discuss, it is the growing sample of radio and X-ray observations of nearby supernovae that are enabling rapid progress in revealing the nature of the GRB-SN connection. The fundamental question at this stage is clearly: which key progenitor property enables such a small fraction of massive star explosions to give rise to relativistic ejecta, and in turn, GRBs? While progenitor mass, metallicity, and binarity are among the most popular explanations, I will discuss how panchromatic observations (radio through gamma-rays) of supernovae and their environments shed light on this puzzle.
18.10.11 (Tuesday)
10:00, ESO room D30, Star and Planet Formation Seminar
"High-energy emission from protostellar jets"
Christian Schneider (Hamburg Observatory)
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"High-energy emission from protostellar jets"

Christian Schneider (Hamburg Observatory)

Abstract

Protostellar jets are an ubiquitous phenomenon of star formation. Up to now, X-ray emission from protostellar jets has been detected only in about a dozen sources. However, these detections clearly demonstrate the existence of a million degree plasma spatially close to the hundred times cooler gas producing the optical emission which is usually studied. I will present recent results from high-energy observations of protostellar jets and their implications for the heating, cooling and launching process.
12:30, ESO room D29, Lunch Talk
"The AMBRE Project: Stellar Parameterisation of the ESO:FEROS Archived Spectra"
Clare Worley (Observatoire de la Cote d'Azur)
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"The AMBRE Project: Stellar Parameterisation of the ESO:FEROS Archived Spectra"

Clare Worley (Observatoire de la Cote d'Azur)

Abstract

The AMBRE Project is a collaboration between the European Southern Observatory (ESO) and the Observatoire de la Cote d'Azur (OCA) that has been established in order to carry out the determination of stellar parameters (effective temperature, surface gravity, global metallicity and individual chemical abundances) for the archived spectra of four ESO spectrographs: FEROS, UVES, HARPS and FLAMES/GIRAFFE.

We have built an automated analysis pipeline that carries out normalisation and correction procedures on the archived spectra and then feeds them into the stellar parameterisation algorithm, MATISSE, which has been developed at OCA. This analysis pipeline has been designed so that is it easily tailored to the archived spectra of each spectrograph. I will present a description of the AMBRE analysis pipeline and the results of the stellar parameter determination of the FEROS archived spectra as well as some examples of galactic archaeology research that will be possible with the stellar parameters for the ESO archived spectra.
21.10.11 (Friday)
12:30, ESO room D29, Lunch Talk
"Massively Multiplexed IFU surveys: dissecting galaxy evolution"
Scott Croom (University of Sydney)
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"Massively Multiplexed IFU surveys: dissecting galaxy evolution"

Scott Croom (University of Sydney)

Abstract

Galaxies are intrinsically complex systems, with multiple components (disk, bulge, halo, black hole, gas, dust, stars etc) which interact with each other in non-trivial ways. Major steps forward have been possible using massive galaxy surveys, such as 2dFGS and SDSS, but these are fundamentally limited by their having only a single aperture per object. I will present the arguments as to why the next major leap forward in our understanding of galaxy formation will be enabled by large surveys containing spatially resolved spectroscopy for thousands of galaxies. This will be driven by new instrumentation which will enable multi-object IFU observations. I will describe the Sydney-AAO Multi-object IFU (SAMI), a multi-object IFU system developed jointly by the University of Sydney and the Australian Astronomical Observatory (AAO), using a new astrophotonic development: hexabundle optical fibres. This system recently had first light on the AAT and already shows the potential for major surveys.
25.10.11 (Tuesday)
12:30, ESO room D29, Lunch Talk
"The role of deep radio imaging in a multi-wavelength Universe"
Edo Ibar (UK Astronomy Technology Centre)
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"The role of deep radio imaging in a multi-wavelength Universe"

Edo Ibar (UK Astronomy Technology Centre)

Abstract

We have employed the Giant Metrewave Radio Telescope and the Very Large Array to image a few legacy fields such as GOODS, Lockman, and SXDF, reaching noise levels of 5-15 uJy/beam. These images in combination with deep multi-wavelength observations have allowed us to describe the very faint sub-mJy radio population -- found to be mainly composed by star-forming galaxies and radio-faint AGNs extending up to z~3. These deep radio observations play an important role in characterising sub-millimetre galaxies; to pinpoint the galaxy and to provide a proxy for the FIR/radio correlation - therefore to best exploit and drive the present Herschel science. In this talk I will show how our data have allowed us to pursue a wide variety of research projects; the far-infrared/radio correlation as proved by Herschel, the radio spectral index of submm galaxies and the nature of the faint sub-mJy radio population. These new findings are providing an important information for what will be observed and the limitations for the upcoming large radio surveys.
26.10.11 (Wednesday)
16:30, Cluster building, seminar room (basement), Universe Cluster Colloquium
"Neutrino oscillations at GSI?"
Avraham Gal (The Hebrew University, Jerusalem)
28.10.11 (Friday)
11:00, ESO Auditorium, Munich Joint Astronomy Colloquium
"Quasar Death"
Martin Elvis (Harvard-Smithsonian Center for Astrophysics)
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"Quasar Death"
Martin Elvis (Harvard-Smithsonian Center for Astrophysics)

Abstract Supermassive black holes pass through several 'ages' - birth, rapid growth at high redshift, moderate growth as quasars, merger growth, and slow growth as radio galaxies and Seyferts, and finally a turn-off. Downsizing of active black holes toward the present means that turned off quasars remain quiescent, a kind of "quasar death". Most of this life cycle is very poorly known, with only the quasar phase well studied. I will describe our new studies, based on both the COSMOS and the SDSS DR5 quasar samples, which shed light on this quasar death phase, as well as adding new complexity to the quasar and merger growth phases. These studies include a careful examination of the Mass-Luminosity plane for quasars, and the nature of 'intrinsically red' quasars based on joint optical and X-ray observations.
12:30, ESO Auditorium, Astronomy Talk for Non-Astronomers
"Supernovae"
Jason Spyromilio (ESO)
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"Supernovae"

Jason Spyromilio (ESO)

Abstract

Some stars end their lives in spectacular explosions, briefly outshining entire galaxies. Supernovae enrich the interstellar medium with elements and stir up the gas in galaxies. As bright standard candles they have been used to measure distances to galaxies and determine the absence of content in our universe. I will present what we know about the explosions and what they tell us about the stars that blow up.

November 2011

02.11.11 (Wednesday)
16:30, Cluster building, seminar room (basement), Universe Cluster Colloquium
"The distribution of dark matter in galaxies"
Paolo Salucci (SISSA, Italy)
03.11.11 (Thursday)
12:30, ESO Auditorium, Astronomy Talk for Non-Astronomers
"The Physics Nobel Prize 2011: Supernova Cosmology"
Bruno Leibundgut (ESO)
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"The Physics Nobel Prize 2011: Supernova Cosmology"

Bruno Leibundgut (ESO)

Abstract

This year's Nobel Prize in Physics is partially based on ESO observations. The distances to galaxies as measured with supernova explosions surprisingly indicate that the expansion of our universe is accelerating. We therefore had to fundamentally change our conception of cosmology - i.e. how the universe “works”. In this talk I will present the research and the ESO involvement in the new results.
16:15, ESO Auditorium, Munich Joint Astronomy Colloquium
"Cosmology from ACT: the small-scale CMB"
Joanna Dunkley (Oxford University)
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"Cosmology from ACT: the small-scale CMB"

Joanna Dunkley (Oxford University)

Abstract

The Atacama Cosmology Telescope has mapped the microwave sky to arc minute scales. I will present recent results from ACT on the angular power spectrum of the Cosmic Microwave Background fluctuations, measuring primordial acoustic oscillations well into the Silk damping tail. I will also describe the extraction of a gravitational lensing signal from the observations, and the detection of galaxy clusters via the Sunyaev-Zeldovich (SZ) effect. I will describe the implications of these various measurements for cosmology, and discuss prospects for the upcoming ACTPol experiment.
08.11.11 (Tuesday)
10:00, ESO room D30, Star and Planet Formation Seminar
"From gaseous giants to super-Earths : Lessons learned over the past decade"
Damien Segrasan (Astronomical Observatory, Geneva University)
12:30, ESO room D29, Lunch Talk
"Cosmography with Lensed Quasars"
Cecile Faure (Lab. d'Astrophysique EPFL, Observatoire de Sauverny, Switzerland)
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"Cosmography with Lensed Quasars"

Cecile Faure (Lab. d'Astrophysique EPFL, Observatoire de Sauverny, Switzerland)

Abstract

Strong gravitational lensing offers a unique opportunity to map the mass distribution in galaxies and to measure the Hubble constant, Ho, at cosmological distance and independent of any standard candle. The COSMOGRAIL collaboration is monitoring about 30 lensed quasars since 2004 with the goal of measuring the so-called "time delays" between the lensed images, a quantity directly related to Ho and to the slope of the mass distribution in lensing galaxies. I will show recent results of our monitoring campaign and improved tools to measure the time-delays and model the lenses.
09.11.11 (Wednesday)
16:30, Garching Cluster building, seminar room basement, Universe Cluster Colloquium
"An alternative scenario of inflation"
Erandy Ramirez (TU Muenchen)
10.11.11 (Thursday)
16:15, ESO Auditorium, Munich Joint Astronomy Colloquium
"Tracing the growth of the first black holes"
Marta Volonteri (University of Michigan)
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"Tracing the growth of the first black holes"

Marta Volonteri (University of Michigan)

Abstract

Massive black holes, weighing millions to billions of solar masses, powered luminous quasars within the first billion years of the Universe. The first massive black holes must therefore have formed around the time the first stars and galaxies formed, at the end of the cosmic Dark Ages. In this talk I will discuss our recent simulations that trace the evolution of massive black holes in the first billion years of the Universe, and review possible strategies for testing our understanding of this early evolution.
15.11.11 (Tuesday)
12:30, ESO room D29, Lunch Talk
"An Infrared View of Galaxy Evolution"
Karina Caputi (University of Edinburgh)
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"An Infrared View of Galaxy Evolution"

Karina Caputi (University of Edinburgh)

Abstract

I will review our most recent results of galaxy evolution at high redshifts, based on the analysis of deep infrared galaxy surveys carried out with major ground-based and space telescopes. I will particularly focus on the study of galaxy stellar mass assembly, and the buildup of massive galaxies over the first few billion years of cosmic time. I will also present our discovery of previously unrecognised galaxy populations at high redshifts using some of the deepest infrared maps. Finally, I will summarise the wide range of infrared galaxy surveys that are now in progress, and discuss their fundamental role to improve our understanding of galaxy evolution, as well as plan the first science programmes that will be conducted with future infrared telescopes, such as the JWST and SPICA.
16.11.11 (Wednesday)
16:30, Garching Cluster building, seminar room basement, Universe Cluster Colloquium
"The search for particle electric dipole moments"
Peter Fierlinger (Universe Cluster, TUM)
17.11.11 (Thursday)
16:15, ESO Auditorium, Munich Joint Astronomy Colloquium
"The Sun's magnetic surface"
Henk Spruit (MPA)
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"The Sun's magnetic surface"

Henk Spruit (MPA)

Abstract

The magnetic field of the Sun is generated in its convective envelope. It is often considered a manifestation of 'the interaction between magnetic fields and turbulent convection'. In the first part of the talk I'll review some observations, old and new, which show that such a turbulent interaction picture fits the observations poorly. The observations, complemented with numerical work, lead to a considerably different conceptual picture of the solar cycle. In a second part I briefly review some spectacular recent successes in realistic numerical simulations of magnetic structures at the solar surface, which have greatly boosted confidence in our ability to reproduce observables with realistic radiative MHD simulations. In the third I discuss the (controversial) possibility that variations of the Sun's magnetic field might have an influence on climate.
22.11.11 (Tuesday)
12:30, ESO room D29, Lunch Talk
"The Herschel Reference Survey"
Alessandro Boselli (Laboratoire d'Astrophysique de Marseille)
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"The Herschel Reference Survey"

Alessandro Boselli (Laboratoire d'Astrophysique de Marseille)

Abstract

As part of the Herschel guaranteed time we defined a project aimed at studying the dust emission properties of a complete, volume limited (15<D<25 Mpc), K band selected sample of 322 nearby galaxies spanning a large range in morphological type, luminosity and galaxy density. This sample has been selected to minimise selection biases and to derive the mean statistical properties of those galaxies dominating the nearby universe. The Herschel Reference Survey has been recently completed. I will review the first results obtained on the study of the far-IR colours of galaxies, on the UV to radio centimetric spectral energy distributions, on the effects of the environment on the dust content and distribution of cluster galaxies with respect to similar isolated objects, and on the study of some intriguing galaxies.
23.11.11 (Wednesday)
16:30, Garching Cluster building, seminar room basement, Universe Cluster Colloquium
"Searches for New Physics in B meson decays with the LHC"
Louise Oakes (Universe Cluster Fellow, TUM)
24.11.11 (Thursday)
16:15, ESO Auditorium, Munich Joint Astronomy Colloquium
"Astronomy at the very edge of black holes"
Giovanni Miniutti (CSIC/INTA, Madrid)
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"Astronomy at the very edge of black holes"

Giovanni Miniutti (CSIC/INTA, Madrid)

Abstract

Accretion onto black holes can liberate a significant fraction of the rest mass energy as radiation and/or relativistic jets. It powers both X-ray binaries and active galaxies. Most of the power is dissipated in the immediate vicinity of the central black hole. Irradiation of the flow produces a characteristic reflection spectrum which, through relativistic blurring, carries imprints of the effects of strong gravity. X-ray observations probe the innermost regions of the accretion flow via X-ray spectra and variability. I will review our current understanding of the phenomena associated with the X-ray emission in accreting black holes and discuss past and most recent observational and theoretical results in the field.
29.11.11 (Tuesday)
10:00, ESO room D30, Star and Planet Formation Seminar
"Asteroid Lutetia may be Earth's baby sister"
Pierre Vernazza (ESO)
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"Asteroid Lutetia may be Earth's baby sister"

Pierre Vernazza (ESO)

Abstract

Isotopic and chemical compositions of meteorites, coupled with dynamical simulations, suggest that the main belt of asteroids between Mars and Jupiter contains objects formed in situ as well as a population of interlopers. These interlopers are predicted to include the building blocks of the terrestrial planets as well as objects that formed beyond Neptune (Bottke et al. 2006, Levison et al. 2009, Walsh et al. 2011). Here we report that the main belt asteroid (21) Lutetia – encountered by the Rosetta spacecraft in July 2010 – has spectral (from 0.3 to 25 microns) and physical (albedo, density) properties quantitatively similar to the class of meteorites known as enstatite chondrites. The chemical and isotopic compositions of these chondrites indicate that they were an important component of the formation of Earth and other terrestrial planets. This meteoritic association implies that Lutetia is a member of a small population of planetesimals that formed in the terrestrial planet region and that has been scattered in the main belt by emerging protoplanets (Bottke et al. 2006) and/or by the migration of Jupiter (Walsh et al. 2011) early in its history. Lutetia, along with a few other main-belt asteroids, may contain part of the long-sought precursor material (or closely related materials) from which the terrestrial planets accreted.
11:00, ESO Auditorium, Special Presentation
"Status report of the National Astronomical Observatory of Japan"
Masanori Iye (NAOJ)
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"Status report of the National Astronomical Observatory of Japan"

Masanori Iye (NAOJ)

Abstract

The presentation will include the status of the Subaru telescope (of which Masanori Iye was the Project Scientist), TMT-J activities (Masanori Iye is Head of the Japanese Thirty Meter Telescope Project Office), studies of high-z galaxies, and others.
12:30, ESO room D29, Lunch Talk
"Hungry Galaxies: Coeval Massive Black Hole and Galaxy Formation at High Redshift"
Nick Seymour (CSIRO Astronomy and Space Science, Australia)
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"Hungry Galaxies: Coeval Massive Black Hole and Galaxy Formation at High Redshift"

Nick Seymour (CSIRO Astronomy and Space Science, Australia)

Abstract

Across cosmic time, powerful radio sources are robust beacons of the most massive galaxies in the Universe. Hence, they trace the co-formation of the massive galaxies and their central black holes as well as the collapse of the most massive dark matter halos. I shall present results from a comprehensive Spitzer/infrared imaging of a sample of 70 high redshift radio galaxies (L3GHz >10^{26} W/Hz, 1<z<5.2). We use these data to determine stellar masses of the host galaxies, AGN mid-IR luminosities and compare these to radio and sub-mm properties. We shall also present early results from an extension of this project to longer wavelengths with Herschel which allows more accurate separation of AGN and starburst components as well as a more accurate estimate of the star formation rate.
18:00, IPP Auditorium, building D2, Cluster evening talk
"Faster than light neutrinos, an optical illusion?"
Ramy Brustein (Ben-Gurion University, Israel)
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"Faster than light neutrinos, an optical illusion?"

Ramy Brustein (Ben-Gurion University, Israel)

Abstract

The OPERA experiment has recently reported that neutrinos propagating through Earth from CERN to Gran Sasso arrive earlier than if they were propagating at the speed of light in vacuum. This measurement has attracted the attention of scientists as well as the general public. Ramy Brustein will first review the measurement and the extensive attempts to find some errors in it. Assuming that the measured time shift is indeed related to the propagation of neutrinos, it will be argued that it is likely not a measurement of Lorentz invariance violation, since Lorentz symmetry is highly constrained in the neutrino sector. Then, it will be argued that the effect has to be both, a matter effect and a collective effect. Ramy will end by discussing our scenario that the index of refraction of the neutrino wave in rock is smaller than unity. This framework can be used to explain the measured time shift and to predict the results of additional experiments, so it can be verified in the near future.

December 2011

01.12.11 (Thursday)
16:15, ESO Auditorium, Munich Joint Astronomy Colloquium
"Observational constraints on the critical metallicity for low mass star formation"
Piercarlo Bonifacio (Observatoire de Paris)
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"Observational constraints on the critical metallicity for low mass star formation"

Piercarlo Bonifacio (Observatoire de Paris)

Abstract

The Universe emerged from the Big Bang with a very simple chemical composition: hydrogen, helium and traces of lithium. The first stars that formed had this chemical composition, however, from the theoretical point of view only very massive stars should have formed, due to the lack of efficient cooling mechanisms that allow the formation of low mass stars. Thus there should exist a critical metallicity, below which no low-mass stars, that are long-lived and may still be observed at the present time, can be formed. To put observational constraints on this critical metallicity we have to search for extremely metal-poor stars and derive the metal-weak tail of the metallicity distribution function. The critical metallicity should manifest itself as a sharp drop in the MDF. In this search one finds many extremely metal-poor stars (EMP) that hold in their atmospheres the fossil record of the chemical composition of the early phases of the Galactic evolution. The chemical analysis of such objects provides important constraints on these early phases and especially on the masses of their progenitors that produced the metals observed in their atmospheres. To pursue this objective it is necessary to treat large amounts of data. With an automatic procedure, we analysed objects with colours of Turn-Off stars from the Sloan Digital Sky Survey to select a sample of candidate EMP stars. During the French-Italian X-Shooter GTO, used as a pilot programme, we observed a small sample of these candidates. We could confirm the low metallicity of our sample of stars, and we succeeded in finding the present record metal-poor star: SDSS J102915+172927 with [M/H]=-5, Z <= 6.9x10^{-7}. This star shows no enhancement of CNO elements, as do the previously found extremely iron-poor stars and, surprisingly, shows no lithium.
06.12.11 (Tuesday)
12:30, ESO room D29, Lunch Talk
"The flow of material in the spiral arms of disk galaxies. Ordered or Chaotic motion?"
Panos Patsis (Academy of Athens)
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"The flow of material in the spiral arms of disk galaxies. Ordered or Chaotic motion?"

Panos Patsis (Academy of Athens)

Abstract

The stellar flow in the arms of spiral galaxies is qualitatively different among different morphological types. The stars that reinforce the spiral arms can be either participating in an ordered or in a chaotic flow. Ordered flows are associated with normal (non-barred) spiral galaxies. Typically they are described with precessing ellipses corresponding to stable periodic orbits at successive energies (Jacobi constants). Contrarily, the spiral arms in barred-spiral systems may be supported by stars in chaotic motion. The trajectories of these stars are associated with the invariant manifolds of the unstable Lagrangian points at the two ends of the bar. We find that the spirals and the outer parts of the bars share the same orbital content. However, we have found also barred-spiral systems with spirals inside corotation, consisting mainly by chaotic orbits. The talk will present the differences between the two flows of material on the galactic disks.
07.12.11 (Wednesday)
16:30, Cluster Building, seminar room, basement, Universe Cluster Colloquium
"Phenomenological constraints on multi-Higgs-doublet models: Flavour Alignment"
Antonio Pich (IFIC, Valencia University - CSIC)
08.12.11 (Thursday)
16:15, ESO Auditorium, Munich Joint Astronomy Colloquium
"Weak Lensing: revealing the dark side of the universe"
Rachel Mandelbaum (Princeton University)
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"Weak Lensing: revealing the dark side of the universe"
Rachel Mandelbaum (Princeton University)

Abstract Weak gravitational lensing, the deflection of light from distant galaxies due to all intervening mass along the line of sight, is one of the most direct ways to observe dark matter. As a result, in the past decade, weak lensing has become a very important tool both for constraining cosmological parameters and for revealing the connection between galaxies and dark matter. I will begin by reviewing some recent, significant observational advances related to both galaxies and cosmology that were made possible by weak lensing. Next, I will outline some of the challenges and opportunities facing the lensing community in existing and upcoming imaging surveys. I will conclude with some perspective on how these challenges will be addressed to do ground-breaking work in the fields of cosmology, galaxy formation, and galaxy cluster formation and evolution with weak lensing observations in the next decade.
13.12.11 (Tuesday)
10:00, ESO room D30, Star and Planet Formation Seminar
"The influence of the turbulent perturbation scale on protostellar disk formation"
Steffi Walch (MPA)
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"The influence of the turbulent perturbation scale on protostellar disk formation"

Steffi Walch (MPA)

Abstract

The collapse of weakly turbulent prestellar cores is a critical stage in the process of star formation. Being highly non-linear and stochastic, the outcome of collapse can only be explored theoretically by performing large ensembles of numerical simulations. Standard practice is to quantify the initial turbulent velocity field in a core in terms of the amount of turbulent energy (or some equivalent) and the exponent in the power spectrum (n=-d log P_k/d log k). Here I will present a numerical study of the influence of the details of the turbulent velocity field on the collapse of an isolated, weakly turbulent, low-mass prestellar core. We show that, as long as n>3 (as is usually assumed), a more critical parameter than n is the maximum wavelength in the turbulent velocity field, Lambda_MAX. This is because Lambda_MAX carries most of the turbulent energy, and thereby influences both the amount and the spatial coherence of the angular momentum in the core. We show that the formation of dense filaments during collapse depends critically on Lambda_MAX, and we explain this finding using a force balance analysis. We also show that the core only has a high probability of fragmenting if Lambda_MAX>R_CORE=2 (where R_CORE is the core radius); that the dominant mode of fragmentation involves the formation and break-up of filaments; and that, although small protostellar disks (with radius R_DISK<20AU) form routinely, more extended disks are rare. In turbulent, low-mass cores of the type we simulate here, the formation of large, fragmenting protostellar disks is suppressed by early fragmentation in the filaments.
14.12.11 (Wednesday)
11:00, ESO Auditorium, Astronomy Talk for Non-Astronomers
"The Fantastic Discoveries of Astronomy made possible by the Wonderful Properties of II-VI Materials"
Jim Beletic (Teledyne)
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"The Fantastic Discoveries of Astronomy made possible by the Wonderful Properties of II-VI Materials"

Jim Beletic (Teledyne)

Abstract

The universe is an amazingly huge place. While humankind has directly explored Earthʼs sister planets with space probes, we donʼt have the means to venture beyond the solar system, and so almost all information about the universe comes from sensing light that happens our way. Astronomy is constantly striving to find better ways to sense the feeble amount of energy from distant stars and galaxies. This quest has led to a new generation of 10-m class very large telescopes on the ground and the deployment of the 2.4-meter Hubble telescope in space. Ground-based astronomy will soon begin construction of 30-meter class extremely large telescopes (ELTs), and the JWSTʼs 6.5-meter mirror will launch by the end of the decade. Possibly more important than the development of bigger telescopes is the rapid advancement in solid state detector technology. The detector revolution was led by silicon CCDs (IV material) starting in the 1970ʼs for sensing visible light, but the II-VI material (HgCdTe) that was developed during the past two decades for sensing infrared light has made the most significant difference in astronomy. Infrared light is the only way to study a wide range of astronomical phenomena, it propagates through dust, and it is required for sensing cooler objects. The distant universe is an infrared universe and several of the next generation facilities will rely mainly, if not entirely, on infrared detectors made from the II-VI materials whose features enable modern astronomy. This talk will present the cutting edge astronomy that is made possible by the wonderful properties of II-VI materials.
16:30, Cluster Building, seminar room, basement, Universe Cluster Colloquium
"Phenomenological constraints on multi-Higgs-doublet models: Flavour Alignment"
Antonio Pich (IFIC, Valencia University - CSIC)
15.12.11 (Thursday)
16:15, ESO Auditorium, Munich Joint Astronomy Colloquium
"Measuring the Cosmos"
Marc Reid (CfA Harvard)
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"Measuring the Cosmos"

Marc Reid (CfA Harvard)

Abstract

Over 2000 years ago, Hipparcus measured the distance to the Moon by triangulation from two locations across the Mediterranean Sea. However, determining distances to stars proved much more difficult. Many of the best scientists of the 16th through 18th centuries attempted to measure stellar parallax, not only to determine the scale of the cosmos but also to test Heliocentric cosmologies. While these efforts failed, along the way they lead to many discoveries, including atmospheric refraction, precession, and aberration of light. It was not until the 19th century that Bessel measured the first stellar parallax.

Distance measurement in astronomy remained a difficult problem even into the early 20th century, when the nature of galaxies ("spiral nebulae") was still debated. While we now know the distances of galaxies at the edge of the Universe, we have only just begun to measure distances accurately throughout the Milky Way. Using the Very Long Baseline Array, we now can achieve positional accuracy approaching 10 micro-arcseconds! I will present new results on parallaxes and motions of star forming regions and the black hole at the center of the Milky Way. These measurements address the nature of the spiral structure, size, rotation speed, and mass of the Milky Way.