German ALMA Regional Centre (ARC) Node

The Atacama Large Millimeter/Submillimeter Array (ALMA) is a revolutionary interferometer for mm and submm astronomy in the Atacama desert in Northern Chile. It is operated by a global collaboration between Europe (ESO), North America (NRAO) and East Asia (NAOJ), in cooperation with Chile. The interface between ALMA and the user communities is provided by three ALMA Regional Centres (ARCs) in Europe, North America and East Asia.

The European ARC (EU ARC) is organized as a coordinated network with a central node at ESO Headquarters in Garching bei München and regional nodes located in Bologna(I), Bonn/Cologne(D), Grenoble(F), Leiden(NL), Manchester(GB), Ondrejov(CZ), and Onsala(S). The concept and the implementation of the EU ARC network has been described in an article in the ESO Messenger (Hatziminaoglou et al. 2015, Msngr. 162, 24).

The German ARC node is a collaboration of the universities of Bonn and Cologne. Its headquarters are located at the Argelander-Institut für Astronomie in Bonn. The German ARC node provides services to ALMA operations, the local astronomical community and the general public:

Newsletters and Announcements

Recent News

3mm VLBI observations in Cycle 8 2021

[11 January 2020]

The phased ALMA array is expected to participate in Global mm-VLBI Array (GMVA) observations during ALMA Cycle 8 2021 (October 2021 - September 2022). Interested parties find an introduction to the GMVA+ALMA observing mode here.

Investigators who are planning to submit a GMVA+ALMA proposal or have submitted a GMVA+ALMA proposal in early 2020 should note the following policies:
  • Proposals submitted at the GMVA deadline in February 2020 have been reviewed by the GMVA observatories, but not by ALMA. On the GMVA side, these projects will be carried over (with their grades) for possible scheduling in the GMVA Session I 2022. These proposals will compete with any new GMVA+ALMA proposals submitted at the February 2021 deadline. On the ALMA side, the proposals must be re-submitted by the ALMA proposal deadline in April 2021 and will be reviewed together with any newly submitted GMVA+ALMA proposals.

  • Proposers who wish to revise their GMVA+ALMA proposal submitted in early 2020 can do so by submitting a revised version to the GMVA before 01 February 2021 in addition to submitting the proposal to ALMA by the proposal deadline in April 2021. In those cases, the proposers should give the code number of the earlier GMVA proposal that is superseded.

  • New proposals for GMVA+ALMA must be submitted to the GMVA before the GMVA deadline on 01 February 2021. In addition, a separate proposal must be submitted to ALMA by the deadline in April 2021.

Pre-announcement of the Cycle 8 2021 Call for Proposals

[17 December 2020]

After ALMA Cycle 8 had to be postponed due to the COVID-19 pandemic, the new cycle of observations, referred to as Cycle 8 2021, is anticipated to start in October 2021. A Call for Proposals (CfP) with detailed information on Cycle 8 2021 is expected to be issued in March 2021, with the deadline for proposal submission in April 2021.

In order to facilitate an early preparation, this pre-announcement provides an overview of the anticipated capabilities, configurations and updated procedures. This pre-announcement supersedes the pre-announcement published for Cycle 8 in December 2019. While the global pandemic continues to evolve, interested parties are encouraged to check the ALMA Science Portal for the latest information.

Second European ALMA Regional Centre community assembly

[14 December 2020]

All European ALMA users are cordially invited to a virtual community assembly on December 18 at 11:00 CET, following the pre-announcement for Cycle 8 2021, scheduled for December 17. At this community meeting, the ALMA director will present the latest on the Return to Operations. Participants will then get information on the timeline for the Call for Proposals, ALMA's capabilities and changes in the reviewing process for Cycle 8 2021. Finally, there will be the opportunity to ask questions on all the above in a dedicated Q&A session. The meeting can be accessed via this link.

Upgrade of Helpdesk software on December 3 and 4

[last update: 14 December 2020]

On December 3 and 4 the ALMA Helpdesk migrated to a new service provider, Deskpro. The new Helpdesk system has the same functionality as the current system, but with an enhanced user experience for the ALMA users when creating tickets and interacting with the knowledgebase. We are confident that the new system will further improve the value of the Helpdesk in supporting exciting ALMA science. If you encounter any difficulties or if you have questions related to the new system, please don't hesitate to contact us, either via the Helpdesk or by email to arc at

ALMA training sessions

[last update: 14 December 2020]

The European ARC Network has initiated a series of online topical training sessions focused on the analysis of ALMA and interferometric data in general. The sessions cover a wide range of topics of interest to the ALMA user community with the aim to help users gain expertise in working with interferometric data.

The topics of the first three ALMA training sessions are
1. Imaging with the ALMA Pipeline (December 4, 2020, 11:00 CET)
2. ALMA Science Archive update and ARI-L (December 15, 2020, 11:00 CET)
3. UVMultiFit (January 15, 2021, 11:00 CET)

The duration of each training session is approximately one hour and includes a live demo and an interactive Q& A session. More details on these and future sessions can be found in the EU-ARC announcements.

ALMA during the COVID-19 pandemic

[last update: 16 November 2020]

Six months after the ALMA Observatory had to be shut down due to the rise of the COVID-19 pandemic in Chile, ALMA has started the long process of recovering the telescope array, ultimately leading to operations and science observations. During the shut-down, almost the whole ALMA site was shut down, with a ALMA Caretaker Teams ensuring the safety and security of the ALMA Observatory.

On 21 October, ALMA started the Operation Support Facility (OSF) Ramp-up phase, during which the Operations Support Facility is returned to normal service, including food service, the opening of labs and offices, and the confirmation of the stability of critical services. The total duration of this phase is expected to be approximately 50 days, contingent on the gate reviews, after which the Array Operations Site Phase 1 should commence, starting with the technical building and associated infrastructure, before moving to the final phase of powering and recovering antenna elements.

ALMA is stepping through a number of carefully defined phases as part of the Return-To-Operation (RTO) procedure, following the philosophy of the Chilean paso-a-paso (step-by-step) return to normal life within the Country. More details on the recovery plan can be found here.

The Cycle 8 Call for Proposals remains suspended. It is anticipated that the Cycle 8 Call for Proposals will open again in 2021 March with the start of ALMA Cycle 8 in 2021 October. ALMA Cycle 7 will continue through 2021 September, with currently non-completed projects ranked A, B and C remaining in the observing queue.

The ALMA proposal preparation support tools produced by the German ARC node in response to the Cycle 8 Call for Proposals in spring 2020 remain available to the community. When the new Cycle 8 Call for Proposals will be issued, these tools will be updated accordingly. In addition, the German node will again offer a drop-in proposal clinic via zoom.

Operations at the German ARC node under the current COVID-19-induced restrictions

[last update: 16 November 2020]

In light of the COVID-19 pandemic, the German ARC node and the hosting universities of Bonn and Cologne have taken measures against the spread of the corona virus. While the crucial infrastructure is kept running with minimum staff on site, most of the staff work in home office and meet regularly in video conferences.

By means of remote computing, emails and video-conferencing, the staff of the German ARC node continues to provide all services of an ARC node including user support and training on a best effort basis. In the months of April through August, the node successfully conducted the hands-on training course "Radio Interferometry" via zoom. While meeting in person is discouraged, ALMA users are very welcome to contact the staff via email or via the helpdesk. Consultation and practical help via video conference systems can be arranged on short notice.

Regular updates on the status of ALMA and the German ARC node will be posted on this webpage and at the ALMA Science Portal.

The First 60000 ARI-L Images are Now Available in the ALMA Science Archive

[13 October 2020]

The first 60000 data cubes and continuum images generated by the Additional Representative Images for Legacy (ARI-L) ALMA development project are now available to download from the ALMA Science Archive (ASA). In addition to the primary-beam-corrected images, the released products also include the primary beams, and mask for all targets and calibrators of more than 1200 Cycle 3 and 4 datasets. More information on the European development project ARI-L can be found here.

The ARI-L image products can be retrieved from the ALMA Science Archive as Externally delivered products on the Request Handler download page directly listed below the ALMA data. Furthermore, all the corresponding calibrated measurement sets are stored on the INAF-IA2 facilities and can be requested through the ARI-L project website.

European ALMA Community Assembly on 08 October

[02 October 2020]

The European ALMA Regional Centre invites all European ALMA users to a short virtual community assembly on October 8 at 10:00 CEST. After a long period of suspended science observing, there is now a path towards getting back on sky and collecting science data with ALMA again. The meeting will include an update on the timeline for recovery and offers an opportunity for questions on individual ALMA projects and support from the European ARC network. The meeting can be accessed via this link (Microsoft Teams).

New Community Activity: Redesign of the ALMA User Experience

[01 October 2020]

ALMA is launching a new global project to Redesign the User eXperience (RedUX). As part of RedUX, focus groups will discuss specific aspects of the ALMA user experience. All ALMA users and prospective ALMA users are invited to help shape the future of ALMA by joining a focus group. (As a token of appreciation, contributors to RedUX will receive a small gift at the end of the provess.) Volunteers are kindly asked to fill in this form.

Release of Full Polarization ALMA Test Data

[01 October 2020]

New data sets taken as part of the Extension and Optimization of Capabilities effort (EOC) have been released on 01 October 2020. 3C279 and Orion-KL were targeted to test, implement, and determine the accuracy of the linear-polarization mosaicking observing mode of ALMA. More details on the newly released data can be found here, information on all science verification data including the latest ones is listed here.

Successful Hands-on Training: Mastering Radio Interferometry via ZOOM

[last update: 08 September 2020]

Throughout the lock-down in Germany (April - July 2020), the German ARC node offered the hands-on training course Radio Interferometry: Methods and Science in the form of an interactive course via zoom. The Master-level course, which attracted more than 25 participants from Germany and abroad, was open to Master students, PhD students and more senior astronomers interested in the data reduction and analysis of radio interferometric data. After a brief review of the basic concepts of radio interferometry, the participants were guided through the various steps necessary to create fully calibrated data cubes from interferometric raw data. In the second part of the course, the participants learned how to construct images and data cubes from the calibrated data and how to analyze their interferometric data. For more details of the course, please see the course homepage.

The next training course in Radio Interferometry is anticipated to start in April 2021.

ALMA at the EAS 2020

[last update: 08 September 2020]

The Special Session No. 13 (SS13) Eight years of ALMA ground-breaking results: A joint venture between the ALMA user community and the ALMA Regional Centres was organised as part of the yearly meeting of the European Astronomical Society. The conference was conducted as an online conference on June 29 - July 3, 2020, in total counting 1777 participants.

The three sessions of SS13 on Friday, July 3, 2020, covered the wide field of ALMA-related research and development, from the newly commissioned observing modes to innovative analysis tools needed to exploit the wealth of ALMA data to the first exciting science results of the ALMA Large Programmes.

Requesting calibrated data in Europe

By popular demand, the EU ARC has implemented a service which permits ALMA users to request the calibrated data for a given dataset (Member Obs Unit Set, MOUS) to be made available for download. The service is open both for ALMA PIs or Delegees with proprietary ALMA data and for archival users wanting to use datasets for which the proprietary time has expired. For a description how to request calibrated data, please go here.

Highlights der Physik in Bonn

The 19th edition of the science festival Highlights der Physik took place in Bonn on 16-21 September 2019. This year's theme was Show yourself! Making the invisible visible. The core of the science festival was a hands-on exhibition on the Münsterplatz with approximately 50 exhibits on physics and astronomy. Scientists from Bonn and other parts of Germany were available for questions, explanations and discussions. There were also science shows, live experiments, the EinsteinSlam, a junior laboratory, workshops, a school competition, numerous lectures and lots of science to touch and try out.

Throughout the festival, the German ARC node welcomed visitors at their exhibition stand, which focussed on ALMA and the principle of radio interferometry. An interactive model of ALMA allowed the public and interested colleagues alike to define a configuration, conduct their own interferometric observations and view the resulting images in real time.