Welcome to the European ALMA Regional Centre Newsletter!
This Newsletter, which appears on a bimonthly basis, is a compilation of recent European ALMA Regional Centre announcements. In addition to these, the Newsletter provides an inside look into ALMA operations, showcases some of the exciting science carried out with ALMA by our European colleagues, and informs you about ALMA or ALMA-related meetings.
Cycle 7 PI science observations have been continuing, although with some significant interruption due to snowstorms at the end of May and in mid-June. Combined with pandemic conditions affecting maximum staffing levels at the site, this led to a delay in reaching the 12-m Array C43-7 configuration (completed on 12 July). Unfortunately, the delay has an impact on the configuration schedule for the remainder of Cycle 7.
A visibility amplitude calibration error that affects fields containing strong line emission has been discovered in ALMA interferometer observations up to and including Cycle 7.
ALminer (ALMA archive mining and visualization toolkit) is a novel Python-based code that enables users to efficiently query, analyse, and visualize the ALMA Science Archive. Users can programmatically query the archive for positions, target names, or any other keywords in the archive metadata (e.g. proposal title, abstract, scientific category) in a simple way. For more information about how to install and use ALminer, please visit the documentation or GitHub pages.
The training series I-TRAIN organised by the European ARC Network will be paused during the European summer months and then resumed in the autumn. In the meantime, videos and materials of the past sessions can be accessed from the ALMA Science Portal, including the last trainings on self-calibration and polarisation observations with ALMA.
The UK ARC Node at the Jodrell Bank Centre for Astrophysics invites applications for a postdoctoral research associate position to work as a support astronomer for UK ALMA users. The closing date is 09 August 2021.
On 2 July 2021, theEU ARC CalMS service provided the calibrated dataset (MOUS) number 1001.The service was launched in October 2019 and has now been extended to be capable of serving up to several 100 MOUSs per month.
The ALMA Science Archive query interface can now show all sources from SIMBAD and NED that fall into any of the ALMA observations. It is furthermore possible for the users to search for particular categories of sources.
Luke joined the ARC at ESO in October 2018, following a 4-year position at the Dutch ARC node, Allegro, where he studied phase calibration and the effect of scaling the WVR solutions. At the ARC he is involved with Extension and Optimization of Capabilities (EOC), with a specific focus on long-baseline high-frequency observations and the Band-to-Band technique. He is also the EU ALMA pipeline contact.
Scientifically, Luke studies high-mass YSOs using mm interferometers in search of bona-fide protostellar disks.
Dr. Edwige Chapillon
Edwige is the manager of the IRAM ARC node in Grenoble since 2016 and she is mainly involved in User Support activities. She also participates in the operation of NOEMA as astronomer on duty and supporting the users.
Edwige started to be involved in the ALMA project in 2011, when she joined the Taiwanese ARC node at ASIAA (Academia Sinica Institut of Astronomy and Astrophysics). In 2013 she returned to France at the Bordeaux observatory (Laboratoire d'astrophysique de Bordeaux) as assistant astronomer. She is delegated to IRAM to join the IRAM ARC node.
Scientifically, Edwige is interested in star formation in general and in the study of protoplanetary disks in particular, trying to infer their physical structures thanks to molecular observations.
ALMA science highlight
The first 3-mm ALMA survey of protoplanetary discs:
evidence of large grains in the Lupus region
Gallery of the 3-mm-continuum emission from protoplantary discs in the Lupus region. In contrast with theoretical expectations, the discs' 3-mm emission is spatially extended, implying the presence of large (mm-sized) grains at large distances from the star. Each image covers a field of view of 3 arcsec squared (Tazzari et al. 2021a).
Observations at sub-mm/mm wavelengths have long been used to infer the size of dust grains in protoplanetary discs, a key parameter needed by theoretical models to set the initial conditions for planet formation.
Since most long-wavelength observational campaigns typically targeted individual sources or very limited samples of discs in different regions, a true statistical perspective on the abundance and on the spatial distribution of mm-sized grains was missing.
Thanks to the sensitivity of ALMA, Tazzari et al. (2021a) have been able to target at 3 mm the 36 brightest protoplanetary discs in the Lupus star-forming region (55% of the sample) with deep observations (rms noise 20-50 μJy/beam) at 0.35″ resolution. Combining this new 3 mm data with previous ALMA surveys at 0.89 and 1.3 mm, the authors have assessed the level of grain growth in the relatively young Lupus region. They find that the typical spectral index between 0.89 and 3.1 mm is 2.23 ± 0.06, in all cases smaller than the ISM-like value of 3.0. These results can be readily interpreted with the widespread presence of grains larger than 1 mm. Thanks to an in-depth multi-wavelength analysis of the ALMA visibilities, by measuring the disc continuum sizes at 0.89, 1.3, and 3.1 mm, Tazzari et al. (2021b) obtained the strongest evidence to date that large mm-sized grains must be present in most Lupus discs. This is true not only close to the star - as predicted by radial drift models - but throughout the disc extent: an indirect evidence that dust trapping in local pressure maxima, possibly associated with the presence of protoplanets, must be effective in these discs.
From August 24 to 27, 2021, IRAM will host the virtual 50th Young European Radio Astronomers Conference (YERAC).
YERAC is a real opportunity for graduate and doctoral students, as well as young postdoctoral researchers to meet together, present their work, tap into different radio-astronomical subjects, and discuss research done by others. Important dates:
This workshop will be held online during the week of September 27-30 (inclusive), 2021. Following the first two of three workshops intended to promote discussion of upgrades that will realize the ALMA 2030 vision, we plan to complete the workshop trilogy with this ALMA Front-End Development Workshop.
This workshop is intended to be relatively small and focused, but participation from all ALMA regions and the rest of the world is explicitly welcome. Registrations are open and abstracts can be submitted here until July 16, 2021. Potential participants can inquire with the organization about late submission of abstracts, via ALMA_FED_2021@eso.org.
The 10th IRAM 30-meter School on Millimeter Astronomy will be held on-line, on 15-19, 22 and 23 November2021. On-line registration will open shortly.
The school will combine lectures on millimeter astronomy with observations using the 30-meter telescope. Lectures will be given by experienced scientists and 30-meter observers, covering a wide range of topics. In addition, the school will include lectures on instrumentation, observing techniques, and data processing.
The lectures will be complemented by practical work using the 30-meter telescope. Unlike previous schools, in this edition all observations will be conducted in remote mode.
The school is primarily meant for young researchers with little previous experience in millimeter astronomy. Due to the constraints imposed by the practices at the telescope, the school attendance will be limited to about 60 students who will be selected on the basis of their interests, experience, and references.
