NRAO eNews
Volume Vol#, Issue Iss#
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NRAO eNews
Volume Vol#, Issue Iss# • Day# Month# Year#
NRAO/GBO Status
This is week six in Infectious Disease Operating Status (IDOS). The North American NRAO/GBO instruments are all operational. IT systems are performing well. We are planning to remain in IDOS until Monday, 1 June 2020.
I have received no new reports of NRAO or GBO staff receiving medical care for COVID-19. Strict physical distancing, and monitoring whenever possible your external interactions (necessary shopping, people visits, etc.) remain important. For staff visiting the NRAO facilities regularly (skeleton crew) or occasionally, face coverings are required.
This week, a document describing the procedures we will follow to restart office work in Charlottesville, Virginia was distributed internally for broad comment. The NRAO Edgemont Road facility is going first to define these procedures (which should be similar for the office buildings and functions across NRAO and GBO), and I hope we can start implementing them soon. Efforts continue to document field (telescope) key areas, essential activities and the personal protective equipment (e.g. masks, gloves, suits) across the Observatories. More news on our return to the buildings, and approaches to enable more field corrective and preventative maintenance work, will be distributed in coming weeks.
At the national level, we are seeing discussions of the widespread removal of work and personal restrictions, with significant differences of opinion apparent. As an essential service, and with the support from the National Science Foundation that we are receiving, we have full flexibility to make the best possible decisions for our staff about when and how to modify/remove our work restrictions. In all cases, we have another five weeks in IDOS, at which point we will have more data. Infection rates have slowed in major metropolitan areas over the past week or two, which is an important piece of news during a terrible time.
Upcoming Events
[Rescheduled] Compact Objects and Energetic Phenomena in the Multi-Messenger Era
Jun 23 - 25, 2021 | Saint Paul, MN
Postponed Events
The following NRAO-related conferences have been postponed owing to concerns about the COVID-19 coronavirus. Please consult the conference websites (links below) for details.
From Cells to Galaxies 2020: Exploring the Synergies between Radio Astronomy and Medical Imaging
New Dates TBD | Santa Fe, NM
17th Synthesis Imaging Workshop
New Dates TBD | Socorro, NM
Multiphase Gas in Galaxy Groups
New Dates TBD | Charlottesville, VA
COVID-19 Impacts on VLA Reconfiguration & Special Call for Exploratory Director's Discretionary Time
To address concerns with coronavirus and protect the health of its staff, the NRAO entered into an Infectious Disease Operating Status (IDOS) on March 16. Very Large Array (VLA) observing continues, but with most NRAO-New Mexico staff working from home and maintenance being performed on an as-needed, call-out basis. The IDOS currently remains in effect until June 1.
The reconfiguration of VLA antennas from the array's C- to its B-configuration was originally scheduled for May 11-27. The reconfiguration requires a large number of staff, and the work involved under IDOS makes it difficult to maintain proper social distance and potentially requires widespread use of Personal Protective Equipment (PPE) that is currently in short supply. In view of the IDOS and the attendant constraints imposed upon the conduct of the work, the beginning of the VLA's reconfiguration will be postponed by four weeks, from May 11 to June 8. If NRAO operating status returns to normal at that time, the reconfiguration may proceed on June 8. In the event IDOS is extended, VLA staff are revisiting and modifying antenna move procedures with the goals of maintaining social distance and identifying and procuring the type and quantity of PPE required to perform the antenna moves in early June.
The additional observing time in C-configuration made available by postponing the reconfiguration will be partially filled by existing approved programs in the Semester 2020A proposal queue. Additionally, this NRAO Announcement serves as a Special Call for Exploratory Proposals for Director's Discretionary Time (DDT) to make use of the additional available time. In particular, we encourage proposals with Local Sidereal Times (LSTs) in the range 1900 - 0800 hours, and that can use frequencies up to 12 GHz. This LST range occurs mostly during daytime throughout the extension of the C-configuration; the recommended frequency range is less vulnerable to poor weather during daytime.
Further details are available for this special DDT call for proposals.
ALMA Program News
ALMA Cycle 8 Call for Proposals Suspended due to COVID-19
The COVID-19 crisis has continued to affect the global community, including ALMA users and staff. ALMA operations remain suspended, as announced on 20 March. Under these difficult and unprecedented circumstances, the ALMA Director, with support from all Executives, has decided to suspend the submission of Cycle 8 proposals until further notice. The Cycle 8 proposal submission server was closed as of 15:00UT on Friday, 17 April, 2020.
We appreciate that the community has worked hard on new science ideas for Cycle 8, even under such difficult conditions. We also realize the work the community has done in generating an exciting Cycle 7 observing program. At this time, our first priority is the health and well-being of the global community.
The ALMA Board is meeting this week remotely to discuss courses of action. New timelines for Cycle 7 and Cycle 8 will be announced on the Science Portal in the coming weeks as the global situation evolves.
These times offer unprecedented stress and challenges for our community members and their families. Our thoughts go out to all those affected by the current situation. The Regional ARCs continue to provide support to their communities. Please contact the ALMA Helpdesk if you have any questions or concerns.
Cycle 8 Call for NA ALMA Development Study Proposals
The Proposal Deadline for the Cycle 8 Call for NA ALMA Development Study Proposals remains 2020 May 1.
ALMA and You!
Win prizes like exclusive NAASC mugs and other cool limited-edition swag!
At the North American ALMA Regional Science Center (NAASC), we are making the best of staying at home by virtually getting to know our users and potential users alike. If you attended the Winter 2020 American Astronomical Society meeting in Honolulu, you may have noticed the fantastic prizes offered for simply filling out some information on your use of ALMA and the NRAO outreach programs.
To help us better understand you, the ALMA user (and possibly more importantly, the non-ALMA user), we ask you to take a short survey (seriously, will only take a minute or less) to gauge demographics, scientific interests, and familiarity with ALMA and NAASC programs in the hopes that we can better provide resources and information to the scientific community. The survey is online.
Because no survey would be complete without a prize, we're offering "a grab bag of NRAO swag" with limited edition prints and artwork, stickers, mugs, and other gifts to hopefully brighten your day! Winners will be chosen randomly as surveys come in. The first winner will be announced 15 May 2020, so get your survey in early! We also encourage you to share this survey among friends and colleagues in the scientific community who aren't already ALMA users. Note that only one survey entry is allowed per user!
Stay healthy and safe!
Rescheduled Conference: Please Save the Dates
Due to COVID-19 concerns, the conference Compact Objects and Energetic Phenomena in the Multi-Messenger Era, originally scheduled for 14-16 July 2020 in Saint Paul, MN has been rescheduled for 23-25 June 2021. We hope you will be able to join us next year. As new timelines are set, abstract submission and registration will start afresh. Stay tuned.
Salts as Tools for Stellar Disk Measurements with the ngVLA
ALMA (NRAO/ESO/NAOJ); NRAO/AUI/NSF; Gemini Observatory/AURA.
The Orion BN/KL outflow showing the location of the detected salt disk, with an image of the disk inset (Ginsburg et al. 2019). The spectrum (top) shows the salt line forest in one of the planned ngVLA bands. While ALMA can detect these lines in nearby objects, the ngVLA will allow us to perform these measurements galaxy-wide.
[click to enlarge]
Material travels around young stars in disks that follow orbits described by Kepler's laws, and we measure these motions to infer the mass of the central stars. This dynamical approach is the most reliable and accurate tool we have to determine the masses of accreting young stars. However, in the most embedded, rich environments like the Orion Nebula Cluster, and around any high-mass young stars, the molecules we like to use for these measurements are often hidden by the cloud.
The recent discovery (Ginsburg et al. 2019) of salts, both ordinary table salt (NaCl) and the common food additive potassium chloride (KCl), in orbit around Orion's Source I opens the possibility of using these rarer molecules to measure protostellar masses. Salts are rarely seen in the interstellar medium (McGuire 2018): they adsorb onto dust grains, so rare conditions – high temperatures and densities – are needed to release them into the gas phase. These conditions are realized in disks around young stars and in the atmospheres of dying stars.
The lowest rotational transitions of NaCl and KCl are at longer wavelengths, starting at 4 cm for KCl J=1-0 and 2 cm for NaCl. The first nine (NaCl) and fifteen (KCl) transitions are within the planned ngVLA frequency range. These molecular transitions are unique probes of the rapidly-spinning inner disks around young stars, as lower-mass molecules have rotational transitions limited to higher frequencies, where the inner-disk dust is often optically thick. The ngVLA will have an ability to measure protostar masses throughout our Galaxy with tools unavailable to any other telescope.
This article continues a regular feature intended to highlight contributions to the ngVLA Science Book. We are especially interested in showcasing work done by early-career researchers. Anyone wishing to volunteer to author a feature should contact Joan Wrobel.
Recent Media Releases
From the Archives
Ellen Bouton
[click to enlarge]
About this month's photo:The first move of a Very Large Array antenna across Route 60, 18 January 1980. According to the account in The Observer (vol. 21, no. 1, page 39), "VLA crews moved an antenna 5.2 km out the North Arm, thus necessitating the first antenna crossing of Rt. 60. Many turned out to witness the event, including NRAO personnel, news media, and the State Highway Dept., who came to measure traffic disruption and check safety procedures.... Rubberneckers rubberneck, gawkers gawk and we all cheer as Route 60 is crossed with little or no effort." The North arm track was still incomplete, and engine and ballast cars belonging to Wm. A. Smith Company were hard at work preparing the final section.
From the Archives is an ongoing series illustrating NRAO and U.S. radio astronomy history via images selected from our collections of individuals' and institutional papers. If readers have images they believe would be of interest to the Archives, please contact Ellen Bouton.
