6th Netherlands ALMA Science Day: Dec. 8, 2022

Allegro announces the 6th Netherlands ALMA Science Day, that will take place in person at Leiden Observatory on Thursday, December 8, 2022. At the Science Day, we will highlight the latest scientific results obtained with ALMA by the Netherlands astronomical community. The meeting will also allow ample time to discuss user experiences and other ALMA related topics. Registration for contributed talks is now open (deadline: Nov. 25, 2022) and we welcome contributions in all science areas. 

Following the Science Day, on Friday, December 9, 2022, we will also host an introductory ALMA Data Reduction Training Day. At this workshop, Allegro fellows will introduce CASA and ALMA data reduction techniques, share tips & tricks, and offer hands-on training in exploring the ALMA archive, self-calibration, imaging, and data analysis.

>>> Registration Form <<<


Program December 8, 2022
1000-1005 Welcome (Allegro)
1005-1020 Violeta Gamez Rosas (Leiden) Kinematics of the molecular torus in NGC 1068
1020-1035 Joshua Butterworth (Leiden) Understanding if molecular ratios can be used as diagnostics of AGN and starburst activity: The case of NGC 1068.
1035-1050 Ko-Yun (Monica) Huang (Leiden) Reconstruct shock history in NGC 253 with ALCHEMI
1050-1105 Mathilde Bouvier (Leiden) Sulphur-bearing species in NGC 253: what do they trace?
1105-1120 Ian Roberts (Leiden) Gas Compression from Ram Pressure in Nearby Cluster Galaxies
1120-1145 Gergö Popping (ESO) The latest from ALMA
1145-1205 ALMA Q&A and discussion
1205-1300 Lunch
1300-1330 Rychard Bouwens (Leiden) The REBELS Large Program
1330-1345 Ivana van Leeuwen (Leiden) Dust-obscured star formation at z ∼ 6 from [CII] selected companion galaxies
1345-1400 Raffaella Morganti (ASTRON, Groningen) On-going feeding of the radio galaxy 3C84
1400-1415 Di Wen (Groningen) Testing Primordial Black Hole Dark Matter with ALMA Observations of Strong Gravitational Lensing
1415-1430 Hector Olivares (Nijmegen) EHT and black hole physics (tbd)
1430-1445 Short break
1445-1500 Margot Leemker (Leiden) Hot or cold: finding the temperatures in transition disks using ALMA
1500-1515 Logan Francis (Leiden) Accretion Burst Echoes as Probes of Protostellar Environments and Episodic Mass Assembly
1515-1530 Milou Temmink (Leiden) Investigating the Cold Chemistry in the Asymmetric Disk of HD 142527
1530-1545 Lucas Stapper (Leiden) Herbig disks: flat vs flared, really?
1600 End of meeting
ALMAxLeiden - Lettering

ALMAxLeiden- “The Great Telescope Adventure” walking tour launched in Leiden

As part of the European City of Science Leiden 2022 project, Allegro has been developing a series of self-guided walking tours to introduce the public to ALMA and radio interferometry. The first tour entitled “The Great Telescope Adventure” has now launched. Participants take on the role of young researcher Robin, who is visiting ALMA only to find that all of ALMA’s antennas have stopped working. It’s then up to them to get ALMA functioning again by visiting and reactivating a number of ALMA antennas one by one. As the tour progresses and more antennas come online, the image of the object Robin is observing will become clearer revealing how the process of interferometry works. During the tour Dr Maria Gomez serves as a guide who offers interesting facts about radio astronomy, ALMA and connections to Leiden. The route of the walking tour visits several landmarks in the centre of Leiden, is 5.2km long and can be completed in roughly 1.5 hours. You can find out more about ALMAxLeiden on the ALMAxLeiden website or go directly to the English Tour or the Dutch Tour to try them out.

Instructions from CASSIS cookbook

Allegro releases CASSIS cookbook

Allegro has developed a simple cookbook that describes how to use CASSIS, a free interactive spectrum analyser. It is a powerful and user-friendly software to efficiently analyse spectral lines, for example to determine physical conditions like column densities and excitation temperatures of different molecules.

The cookbook material can be downloaded from the Allegro website. It describes how to use CASSIS with a special emphasis on ALMA observations, including instructions on how to extract a spectrum from ALMA data in a format that can be read by CASSIS. The document comes with hands-on practice material that can be downloaded as well. The material contains a copy of the cookbook, scripts, an ALMA dataset that can be used to extract a spectrum from, a spectrum formatted for CASSIS, and a folder with codes and files relevant for scripting CASSIS. Detailed instructions on how to install and use CASSIS can be found on the CASSIS website.

Don’t hesitate to e-mail us if you would like to use CASSIS on the Allegro computing nodes or if you encounter any issues using the cookbook.

Enjoy CASSIS in the ALMA era!

Allegro logo

Allegro launches Friends of Allegro 2023 program

Allegro is looking for applicants for its Friends of Allegro 2023 program, which aims to expand and facilitate connections across the ALMA community in the Netherlands. This program is open to Ph.D. students and Postdoctoral Researchers at Dutch research institutes and universities. Members of the Friends of Allegro program will be given opportunities to develop ALMA-related skills and expertise further. They will also help Allegro spread relevant ALMA-related communications within their institutes.

If you are interested in participating in this program, please fill out this form. We will contact successful applicants near the end of December for participation in 2023. If you are interested in learning more, don’t hesitate to contact us at alma@strw.leidenuniv.nl.

Time requested by Cycle

Cycle 9 statistics

ALMA Cycle 9 received a total of 1769 proposals for a requested 27,912 hours for the 12-m array (4300 hours offered), 14,962 hours for the 7-m and 16,096 hours for the Total Power array. This number of proposals has been pretty stable in the past two years (after a record peak surpassing 1830 proposals only three years ago), however the actual number of hours requested for the 12-m array has been growing at every cycle.

For the ACA standalone array, there were 109 proposals submitted (with, respectively, 4100 and 3000 hours requested for the 7-m and total power array). The number of Large proposals submitted in Cycle 9 was 40 (same number as last year) requesting 4349 hours of 12-m array time, 2700 hours from the 7-m array and 3612 hours on the total power array.

Getting time at ALMA is still very difficult. The Cycle 9 oversubscription rate is still the highest in Europe (39% of all proposals had a European PI) with a total of 11,000 hours requested on the 12-m array. The European oversubscription is 7.6, compared to 6.2 in North America, 5.8 in East Asia and 3.7 in Chile.

ALMA has been encouraging its users to increase the hours of time requested according to their science goals. For this reason, the overall time requested per proposal (excluding large proposals) has been slowly growing, with a median of about 12.2 hours per proposal requested for this cycle. The most requested receiver bands are Band 6, Band 7, and Band 3.

Of the total 1769 proposals submitted, 348 had Dutch participation (41 as PI) — these included 19 Large and 12 VLBI proposals. From the Dutch pool, 27 proposals were accepted with grades A+B+C (18 as PI), of which two were Large proposals, nine were VLBI proposals and one was a Target of Opportunity proposal. Requested receivers from the Dutch community range across the band, again with a higher request for Band 6 and 7 (183 and 125 proposals submitted, respectively), but there was also a notable interest for bands 8 and 9 (39 and 26 proposals submitted – 13 and 10 of those were accepted!). This all makes the Dutch community a very active and successful part of ALMA. The science categories of Dutch PIs were also evenly distributed, with slightly more proposals in Cosmology, and then an equal number among Galaxies, star formation/astrochemistry, and circumstellar disks.

For more information, please visit: https://almascience.eso.org/documents-and-tools/cycle9/cycle-9-proposal-submission-statistics

Amplitude and phase calibration errors

Self-calibration and improving image fidelity for ALMA and other interferometers

The high quality of ALMA calibrated data sets allows researchers to tune the imaging parameters to their preferences, and to produce images ready for publication in few steps.
Sometimes the exploratory analysis of calibrated datasets can also show the need for post-calibration processing. Identifying and/or diagnosing imaging problems from structured artifacts, or to identify errors induced from the observations and/or prior calibration, could save valuable time when researchers deal with challenging datasets.

Although there is extensive documentation out there for experts, a document accessible for researchers less experienced with radio interferometry was still missing. Recently, Anita Richards et al. published an internal ALMA memo (620), also available in the ArXiv, with the title “Self-calibration and improving image fidelity for ALMA and other interferometers”.

This document is an up-to-date manual with practical explanations of the errors normally found in interferometric data, and corrections that can be applied.
The main topic is self-calibration, in particular with ALMA data. However, the concepts explained are also relevant for other long-baseline interferometers.
The document includes examples and a quick-start guide for continuum self-calibration, as well as special cases.

Complementary to the ALMA Memo is the I-Train tutorial on self-calibration. In this tutorial, Anita Richards, Emily Moravec, Carmen Toribio, and Andrés Pérez explain and show examples of self-calibration.

Images from Bouwens et al. and Brunken et al.

ALMA probes atoms and molecules, near and far

ALMA’s supreme capabilities to detect spectral lines across the Universe are beautifully illustrated in two recently published papers by astronomers in the Netherlands. Bouwens et al. (2022, ApJ 931, 160) give an overview of the design and results of the ALMA Large Program REBELS. Using an efficient selection scheme, REBELS detects no less than 18 star-forming galaxies with bright [CII] 158 µm ISM cooling lines, out of a sample of 40 z>6.5 systems. This makes ALMA [CII] searches as efficient as Lyα to find high-redshift star-forming galaxies. Brunken et al. (2022, A&A 659, A29) stay closer to home and detect Complex Organic Molecules (COMs) in the highly asymmetric planet-forming disk around the young star IRS48. The disk around this star has a very pronounced ‘dust and ice trap’ where material accumulates, and future planet(esimals) may form. Brunken et al. report the first detection of dimethyl ether (CH3OCH3) vapor in a planet-forming disk, and a tentative detection of methyl formate (CH3OCHO) vapor. The presence of these molecules shows that a wide variety of oxygen-carrying COMs are present in the birth environment of planets. As these two papers show, wherever ALMA turns its ‘eye’, atoms and molecules leap out at us.

ALMA Proposal Preparation Day 2022

The Allegro ARC Node would like to invite you to attend a proposal preparation workshop on March 28, 2022. The aim of this workshop is to assist you in making the most out of ALMA’s new capabilities, getting an overview of the new modes offered, and proposal preparation through the ALMA Observing Tool (OT). We will also offer guidance with writing double-anonymous proposals and in the new stages of proposal writing and reviewing (the “distributed proposal review process”) that has been in use from Cycle 8 2021. An overview of important dates and what’s offered in Cycle 9 will be released with the Call for Proposals on March 24, 2022.

The workshop will consist of:

  1. an in-person event with the Allegro team on March 28th with a few presentations and an extensive Q&A session. The workshop will take place at Leiden Observatory, but we will organise streaming for those unable to travel.
  2. individual 1-1 support that can be booked at any time (e-mail us)

You can register to attend the workshop using this registration form. Deadline for registration: March 20, 2022

Program March 28, 2022
before 11:00 Arrival to Allegro offices (HL 1122)
11:00-11:30 Welcome coffee/tea & cookies (HL 11th floor)
11:30-12:00 ALMA science overview Katharina Immer & Aida Ahmadi
12:00-12:20 ALMA Call for proposals & capabilities in Cycle 9 Violette Impellizzeri
12:20-13:15 Lunch
13:15-13:35 Distributed peer review Katharina Immer
13:35-13:50 Dual anonymous proposal review Andrés Pérez-Sánchez
13:50-14:15 How to write an ALMA proposal Violette Impellizzeri
14:15-14:35 Break
14:35-15:10 The ALMA Observing Tool Ashley Bemis
15:10-15:30 Simulating ALMA observations Alex Hygate
15:30-15:50 Mining the ALMA archive Aida Ahmadi
15:50-16:10 Break
16:10-16:30 Open Q&A session
Registered participants

Michiel Hogerheijde Leiden Observatory
Violette Impellizzeri Leiden Observatory
Alex Hygate Leiden Observatory
Andrés Pérez-Sánchez Leiden Observatory
Ashley Bemis Leiden Observatory
Aida Ahmadi Leiden Observatory
Katharina Immer Leiden Observatory
Marco Grossi Observatório do Valongo, UFRJ
Sander Schouws Leiden Observatory
Maren Hempel Universidad Andres Bello , Chile
Veronica Allen University of Groningen
Wuji Wang Center for Astronomy of Heidelberg University
Pooneh Nazari Leiden Observatory
Simin Tong Leiden Observatory
Thomas Steinmetz Nicolaus Copernicus Center for Astronomy (Torun)
Di Wen Kapteyn Astronomical Institute
Agnieszka Kobak Nicolaus Copernicus Center for Astronomy (Torun)
Alice Booth Leiden Observatory
Lucas Stapper Leiden Observatory
Margot Leemker Leiden Observatory
Bayron Portilla Revelo Kapteyn Astronomical Institute
Marta Frias Castillo Leiden Observatory
Fernanda Roman de Oliveira University of Groningen
Ko-Yun (Monica) Huang Leiden Observatory

Directions to Leiden Observatory

The address of Leiden Observatory is Niels Bohrweg 2, 2333 CA Leiden. Note that this is not the old observatory in the center of Leiden. Instructions on how to get to Leiden Observatory, including transportation from Schiphol Airport or the central trains station, can be found here. Leiden Observatory is located on the 4-5th floors of the Oort building (seen on the right in the photo below), and the Huygens building (the taller building seen on the left in the photo below). Allegro offices are located on the 11th floor of the Huygens building.

Upon arrival and before the start of the event, join us on the 11th floor of the Huygens building for tea, coffee, and cookies. The workshop will take place in room HL 106-109 on the 1st floor of the Huygens building. We will have signs and there is also a reception at the entrance of the building where they can provide you with directions.

For those joining us online, connection details will be sent to you by email before the start of the event.



Useful resources:

I-TRAIN logo

I-TRAIN: Writing & Reviewing ALMA proposals

The European ARC Network invites users to an online training on good practices for writing and reviewing ALMA proposals on March 18th, 11:00 CET.

This training is organised in view of the upcoming ALMA proposal deadline in April, and will serve as a guideline for writing ALMA proposals and in particular anonymous proposals. The training will also offer guidelines on reviewing proposals, how to best give feedback and the ALMA Reviewer Tool. It will include some tips and tricks and plenty of time for discussion and questions at the end. No preparation will be needed for this session, but we encourage everyone to bring plenty of questions for the Q&A.

The duration of this training session will be about one hour. If you have any doubts or questions, do not hesitate to contact the Allegro node at alma@strw.leidenuniv.nl.

Hands up for a community assembly!

Fifth European ALMA Regional Centre community assembly

The Fifth European ALMA Regional Centre community assembly meeting will take place virtually on the 24th of March at 11:00 AM CET and can be accessed via this Microsoft Teams link. During the meeting, staff from the European ALMA Regional Centre will present updates on the current and future ALMA cycle, including the imminent ALMA cycle 9, which is scheduled to be announced the day before the meeting. In addition, you will hear about the support for using ALMA that the European ARC network offers the community. There will also be a dedicated question and answer session where staff from the European ALMA Regional Centre will be on hand to answer your questions.