Welcome to the European ALMA Regional Centre Newsletter!
This monthly newsletter is a compilation of recent European ALMA Regional Centre news and announcements, showcases an exciting ALMA science result by European colleagues and announces upcoming ALMA and ALMA-related meetings and I-TRAIN sessions. In the "Meet the ARC" section, the work of ARC personnel and the services and expertise areas of an ARC node are highlighted. Every month, you can learn an incredible ALMA fact in "Did you know" and give your opinion about a particular ALMA matter in the "Poll of the month". You can also connect with the European ALMA Regional Centre via social media!
The European ARC Network invites users to an introduction to the eXtended CASA Line Analysis Software Suite (XCLASS) on February 16th, 11:00 CET [Zoom].
A new development study, led by the Cosmic DAWN Center (DAWN) at the Technical University of Denmark (DTU, Cophenhagen), started on 10 January 2024. The study aims to explore the feasibility and scientific impact of using focal plane arrays (FPAs) to improve the mapping speed of ALMA, while maintaining its exquisite spatial resolution.
A new development study, led by the Group of Advanced Receiver Development (GARD, Chalmers University, Sweden) started on 19 December 2023. The study aims to improve the sensitivity of ALMA receivers by developing a new low-loss construction technique for the waveguide components.
As previously announced, the workshop 'The promise and challenges of the ALMA Wideband Sensitivity Upgrade' will take place at ESO - Garching from the 24th to the 28th of June, 2024. This upgrade constitutes the top priority of the ALMA 2030 roadmap. It consists of an increase of the instantaneous spectral bandwidth by as much as a factor of four, while retaining full spectral resolution over the entire bandwidth, thus resulting in increases of the spectral scan speed up to a factor of 50 for the highest spectral resolution. In addition, an upgrade of the full signal chain of ALMA — from the receivers and digitizers, all the way through to the correlated data — will result in increases in sensitivity for all observations.
Planetary building blocks survive ice sublimation following accretion outbursts
Left panels: Final images of the dust thermal emission of V883 Ori, in Band 7 and Band 6. The dashed-blue curve indicates the water snowline position, at 80 au as inferred by Tobin et al. 2023. Top-right panel: Spectral index radial profile of the dust emission of V883 Ori between Band 7 and Band 6, including error bars. The disc is optically thick (α~2) in the inner ~20 au. Beyond 50 au, it is optically thin and characterised by α≈2.5, indicating the presence of large particles inside the snowline. Bottom-right panel: Schematic representing the two end-member scenarios for the response of icy particles to water ice sublimation. Credit: Houge & Krijt (2023).
In protoplanetary discs, planets are thought to form preferentially at the water snowline, a region characterised by dramatic changes for dust particles, as the water ice, that is usually deeply embedded within the rocky structure, sublimates. However, it remains a mystery what happens to the leftover rocky structure: does it remain unchanged or does it totally fall apart, if we imagine water ice to act as a glue?
To solve the ice sublimation mystery, Houge, Macías & Krijt (2024) studied V883 Ori, a protoplanetary disc currently undergoing a powerful accretion outburst, which results in intense heating and ice sublimation up to 80 au. They used ALMA observations taken at four different bands (Bands 7, 6, 4 & 3), all characterised by high angular resolutions, to probe the properties of dust particles in V883 Ori. Coupled with dust evolution simulations, they find that large particles are present in the disc, indicating that they survived the intense ice sublimation process when the outburst started.
Given that accretion outbursts subject dust particles to intense heating and stress, their findings highlight the resistance of dust particles in protoplanetary discs. It also suggests a broader implication, as their findings could extend to other environments with more gentle heating, such as icy pebbles drifting through the water snowline.
Meet the ARC
Dr. Ashley Barnes
Ashley joined the European Southern Observatory (ESO) in Garching as a research fellow in November 2022. His responsibilities as part of the fellowship at the ESO ARC include quality assurance and user support. Before this role, he served as a postdoctoral researcher at the Argelander-Institut für Astronomie (University of Bonn) and earned his Ph.D. from a joint program between Liverpool John Moores University (LJMU) and the Max Planck Institute for Extraterrestrial Physics (MPE).
Ashley's research focuses on high-mass star formation and stellar feedback within the Milky Way, Galactic Centre, and nearby galaxies. He primarily utilizes interferometric facilities such as ALMA, NOEMA, and the VLA, while also showing interest in optical and infrared instruments like MUSE, HST, and JWST. His recent work involves the analysis of multi-wavelength observations (including ALMA) as part of the Physics at High Angular Resolution in Nearby Galaxies (PHANGS) survey. Recently, he investigated a massive molecular bubble named "the phantom void" in the nearby disk galaxy NGC 628.
Join the online ALMA training events!
The European ARC Network invites you to the next session of the online training series I-TRAIN, which will be:
Introduction to XCLASS - 16th February 2024
You can find further details on this session below. You can access or subscribe to the calendar of sessions at [calendar URL][iCal address].
Please contact us by submitting a ticket to the ALMA HelpDesk (Department "General Queries") if you wish to provide your feedback on I-TRAIN. Information on the I-TRAIN sessions, including legacy materials and links to YouTube videos from previous sessions, are available in the Science Portal.
The European ARC Network invites users to an introduction to the eXtended CASA Line Analysis Software Suite (XCLASS) on February 16th, 11:00 CET [Zoom].
NGC 2264 refers to both the Cone Nebula (at the bottom of the image) and the Christmas Tree Cluster (inverted on this image where the bright star near the cone depicts the tree topper and the bright star at the top of the image is in the tree trunk). This emission nebula is located in the Monoceros constellation at a distance of about 720 parsec. It was discovered in January 1784 by the astronomer William Herschel.
ALMA poll results December 2023
Did you know...
that you can contact the ESO Education and Public Outreach department (press@eso.org) if you have impactful results that you would like to share with the public? They will help you to identify the potential news value of your results and coordinate potential press releases to publicize them.
