ALMA North American Science Advisory Committee

  • The double loops of DCO+ in IM Lupi show that it is, in fact, loopy. Oberg et al. 2015:
    150923-IMLupALMA nrao.jpg

Contact Information for those calling in.

* Call date: 2015-10-09 1:00 pm EDT or 17:00 UT (Friday (Saturday in Taipei))
  • Duration: 1 hr
    * USA Number: 1-866-692-4538
  • Outside USA +1-517-466-2084
  • Passcode: 9480444#
  • Leaders: R. Osten, P. Jewell, A. Wootten
  • CV Room: 331


  • Attendees: Wootten, Oberg, Lazio, Bolatto, Osten, Scott, Doeleman, Lai, Marrone

--+++ Notes from meeting: notes from 10-09 telecon:

Topics

  1. Old Business
  2. New Business under Discussion.

Discussion Items

  • new ANASAC chair
  • An advertisement seeking ALMA Postdoctoral Fellows has been published today. Please consider, disseminate and otherwise help us get some great candidates to work with at the JAO.
  • New NAASC meetings news at end of meetings section.
  • ASAC f2f Meeting ALMA EDM document repository user: arc

Oct 14

8:30-9:00 closed session

9:00-12:00 Regional reports (0.5 h)

* 5-10 minutes for each region

Charge 2: Review the Cycle 3 Proposal Review Process (2 h)

Quick summary of the cycle 3 PRP (10 min)

Inputs and concerns from regional SACs (5 min x 4)

12:00-13:00

Lunch and ALMA Science Summary Talk by EASAC

13:00-17:00

Charge 3: Review the time allocation of the array with ORR documents (2 h)

  • FYI: including the main array and the ACA, and correcting for the better efficiency of the 7m antennas, ALMA's collecting area is that of 58 12m antennas, near the original specification.
  • +Material for Charge 3c: ASAC has been presented material on image quality and fidelity before, in Feb 2005 in Garching--when the number of antennas was cut to 50 from 64. A charge at that time was:
    • Examine the status of ALMA re-baselining, including rescope options identified to date, and comment on the impacts that the proposed changes will have on ALMA’s scientific capability. The ASAC is invited to comment on the scientific capability of a smaller number of antennas operating simultaneously, specifically 40 or 50.
    • The agenda for that f2f meeting and materials are at http://www.cv.nrao.edu/~awootten/mmaimcal/asac/asacgarchingagendav0.50.html where you will find the memo linked under 'Second Draft'. The ASAC report for that charge is at https://safe.nrao.edu/wiki/bin/view/ALMA/AlmaSac It urged trying to obtain 60 12m antennas. The 66 antenna array has an effective area approximately that of 58 12m antennas I believe, so it is close.
      • As part of this study, there was investigation of the effect of losing antennas or groups of antennas from the array. This was found to be most serious for antennas nearer the center than the outer edges, where the loss was almost unnoticeable.
    • There is also a US National Research Council study on that question, which found that 54 12m antennas (which we ended up with oddly enough) was an effective minimum. For that report please see http://www.nap.edu/catalog/11326/the-atacama-large-millimeter-array-alma-implications-of-a-potential
      • The committee concluded that:
      • A 60-element array would be greatly superior to any current or planned comparable instrument for several decades and would revolutionize millimeter and submillimeter astronomy.
      • Two of the three level-1 requirements, involving sensitivity and high-contrast imaging of protostellar disks, will not be met with either a 40- or a 50-antenna array. It is not clear if the third requirement, on dynamic range, can be met with a 40-antenna array even if extremely long integrations are allowed for.
      • Speed, image fidelity, mosaicing ability,2 and point-source sensitivity will all be affected if the ALMA array is descoped. The severest degradation is in image fidelity, which will be reduced by factors of 2 and 3 with descopes to 50 and 40 antennas, respectively.
      • Despite not achieving the level-1 requirements, a descoped array with 50 or 40 antennas would still be capable of producing transformational results, particularly in advancing understanding of the youngest galaxies in the universe, how the majority of galaxies evolved, and the structure of protoplanetary disks, and would warrant continued support by the United States.
      • Furthermore, it is the committee’s appraisal that a 40-antenna array would retain ALMA’s strong support within the general astronomical community. However, the rapid decline in imaging capability that would result with a further reduction below 40 antennas would erode this support.

Quick summary of the current time allocation (and ORR documents?) (10 min)

Inputs from regional SACs (10 min x 4)

Charge 5: Review the basic performance and function of ALMA at the end of cycle 2 (1.5 h)

*Quick summary of the performance and function (15 min)

*Inputs from regional SACs (5 min x 4)

17:00-17:15 closed session

Oct 15

8:30-9:00 closed session

9:00-12:00

Charge 1: Review the Principles of Proposal Review (PPR) document (1 h)

*Quick summary of PPR document?

*Inputs from regional SACs (5 min x 4)

Charge 4: Review prioritization of new development projects vs. baseline construction capabilities (1.5 h) (N.B. Recall all NA project summaries are in a zipfile distributed in the 2014 Feb 20 Agenda) An updated overview is provided in an attachment here.

*Quick summary of lists, timelines, and costs for new development projects and baseline construction capabilities (10 min)

*Inputs from regional SACs (5 min x 4)

12:00-13:00 Lunch

13:30-16:00

Summarizing discussions and writing draft report

16:30-17:00

Inputs from ASAC to JAO

    • Development: The deadline for submissions in response to the ALMA/NA Call for Development Studies issued in March was 12 June. 15 valid proposals were received from 56 proposers representing 20 institutions requesting a total of $2.528M; $1M is available. The proposals have been reviewed and ranked by referees as nominated by ANASAC. The review panel recommendations for funded studies await NSF consent.
    • ANASAC, NAASC Meetings and Workshop
  1. Science Operations (Lonsdale)
    • Timed Out projects - PIs have been notified. Incomplete datasets will be delivered.
    • Data processing: see John's charts.
    • The first batch of Cycle 3 SBs are now being prepared: long baseline studies
  2. Astronomer Outreach
  3. Date of next meeting
    • Late Sep 2015? (TBC)
    • Proposed dates for 2015 telecons: late September, 5 Nov. Comments please.
  4. VLBI with ALMA Phasing (see attached document)
  5. Other Business

Science Corner

  1. Memos and papers of note
CONFLICT original 6:
    • A revision of North American ALMA Science Center Memo 110 – ALMA Data Rates and Archiving at the NAASC – has been posted online. Memo 110 describes the data flow plans for ALMA, as revised based on recent experience. It is shown that 200 TB/year remains a good estimate of the steady-state data rate, and a data link speed between Chile and the ALMA Regional Centers (ARCs) of 100 Mb/sec will be sufficient for the next decade. It is recommended that the ALMA Observing Tool warning on observational data rates be removed, though observers should still be prompted to keep datasets to workable sizes.
    • North American ALMA Science Center Memo 115 has been posted online: Doubling the Bandwidth of the 64-Antenna ALMA Correlator, by R. Escoffier, R. Lacasse, J. Greenberg, A. Saez, A. Baudry, J. Webber. Memo 115 describes a method of doubling the bandwidth of the baseline ALMA correlator. The proposed approach is to use the present correlator infrastructure as much as possible, but replace most of the circuit cards. This approach will minimize hardware costs, software development costs, and ALMA operations disruptions.
CONFLICT version 8:
    • A revision of North American ALMA Science Center Memo 110 – ALMA Data Rates and Archiving at the NAASC – has been posted online. Memo 110 describes the data flow plans for ALMA, as revised based on recent experience. It is shown that 200 TB/year remains a good estimate of the steady-state data rate, and a data link speed between Chile and the ALMA Regional Centers (ARCs) of 100 Mb/sec will be sufficient for the next decade. It is recommended that the ALMA Observing Tool warning on observational data rates be removed, though observers should still be prompted to keep datasets to workable sizes.
    • North American ALMA Science Center Memo 115 has been posted online: Doubling the Bandwidth of the 64-Antenna ALMA Correlator, by R. Escoffier, R. Lacasse, J. Greenberg, A. Saez, A. Baudry, J. Webber. Memo 115 describes a method of doubling the bandwidth of the baseline ALMA correlator. The proposed approach is to use the present correlator infrastructure as much as possible, but replace most of the circuit cards. This approach will minimize hardware costs, software development costs, and ALMA operations disruptions.
CONFLICT end
  1. Press Releases
  2. ALMA Papers (choose ALMA)

Events of Interest

2015
 
 
 
 
 
Oct 1 2015
 
Start of Cycle 3 observing seasons
 

See also google calendars:
  1. ALMA Science Meetings
  2. ALMA Training Events

-- AlWootten - 2015-10-06

Topic attachments
I Attachment Action Size Date Who Comment
150923-IMLupALMA_nrao.jpgjpg 150923-IMLupALMA_nrao.jpg manage 34 K 2015-10-08 - 14:42 AlWootten The double loops of DCO+ in IM Lupi show that it is, in fact, loopy. Oberg et al. 2015
ADMIT-ASAC-Oct2015.pptxpptx ADMIT-ASAC-Oct2015.pptx manage 1 MB 2015-10-08 - 14:45 AlWootten Report on ADMIT, from L. Mundy
APP_slides_for_Al_2015.pptxpptx APP_slides_for_Al_2015.pptx manage 12 MB 2015-10-08 - 14:46 AlWootten Report on APP, from L. Matthews
ASAC_F2F_meeting_draft_agenda_20151007.docxdocx ASAC_F2F_meeting_draft_agenda_20151007.docx manage 89 K 2015-10-08 - 15:14 AlWootten 7 October agenda version
ASAC_Summary.pptxpptx ASAC_Summary.pptx manage 6 MB 2015-10-08 - 23:16 AlWootten Summary of Progress on Band 2 Prototype ALMA Receiver
ConfProposal_for_Web.txttxt ConfProposal_for_Web.txt manage 3 K 2015-10-09 - 11:13 AlWootten NAASC Conference Spring 2016 Strawman Plan
DevelopmentSummary_AW.pdfpdf DevelopmentSummary_AW.pdf manage 4 MB 2015-10-08 - 13:19 AlWootten NA Development Summary (in progress)
anasac_vlbi_9oct.pdfpdf anasac_vlbi_9oct.pdf manage 30 K 2015-10-09 - 10:44 RachelOsten slide from Shep about ALMA phasing
telecon151009.txttxt telecon151009.txt manage 6 K 2015-10-11 - 11:18 RachelOsten notes from 10-09 telecon
Topic revision: r11 - 2015-12-08, AlWootten
This site is powered by FoswikiCopyright © by the contributing authors. All material on this collaboration platform is the property of the contributing authors.
Ideas, requests, problems regarding NRAO Public Wiki? Send feedback