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* 2010-1-20 14:30 UT
Note 'usual' UT time.
* Note: C. Wilson points out line noise may be muted by pressing *6 which works thru the call center.
* Duration: 1 hr
* Toll Number: NEW; Old number cancelled 1-203-480-8549
* USA Toll Free Number: NEW; Old number cancelled 866-600-8836
* Passcode: NEW; Old number cancelled 3283890
* Leader: Hills, Wootten, Testi, Morita
* Attendees:

Topics

1 Old Business The enhanced Agenda from last meeting is available. Science IPT notes from last month's telecon are unavailable.

Three antennas at the AOS.

Three ALMA antennas working in unison at the AOS. © ALMA (ESO/NAOJ/NRAO), W. Garnier (ALMA)

See other images and animations.

  1. New Business--Project news/updates.(Hills, Peck)
    1. R. Hills
      1. A detailed status report may be found in ALMA Monthly Reports
      2. Brief status report. After review, the commissioning and science verification process is slated to begin 2010 Jan 22. This is exactly a year after 'first light' was achieved.
      3. As announced, Phase closure has been achieved at the AOS.
      4. Three antennas are operating at the AOS after the 20 Nov ascent of DV02. Two antennas are at the OSF being outfitted for interferometry there by early February. R7.0 computing integration and testing has progressed well. On 11 Jan, exactly four hundred years after Galileo identified the fourth Jovian moon, fringes were achieved with ALMA on all four Galilean satellites of Jupiter.
      5. The Control Room at the OSF Technical Facility continues as the center of activity.
    2. Employment
    3. ALMA Science IPT wiki page
    4. Astronomer Outreach: ALMA News. JAO ALMA Webpages. JAONews. NRAO eNews ESO Newsletter No 16 NAOJ News. NRAO ALMA Calendar
    5. Current ALMA System Block Diagram Vers P.
    • Current IPS attached
  2. Directories

Project Scientists

  1. Parametric cuts. In order to recharge project contingency we identified parametric cuts to the budget. So far the only suggestion that appears to have an impact on capabilities is one to reduce the photonic distribution system so that, instead of 4 units which can supply 80 antennas, we have 2 that can do that and two that can supply only 16 antennas. This would presumably slightly limit the sub-arraying flexibility but the details are not yet clear. Software line length correction is another (controversial) option but the intention there would be to do it only if there is no loss of performance.
  2. Change Requests. 234. Change to the “differential” definition for Saturation in the Front-End Technical Specifications and relaxation for the Bands 3 and 4. Todd notes: "With the FE CDR looming in mid-February, the question of gain compression has returned. Band 3 cold cartridges appear to not be meeting the gain compression spec of 5%. What to do about it? Here is a link to discussion on the AlmaCal page. Here are the relevant minutes from yesterday's FE IPT meeting (which I do not attend). Excerpt: "The Calibration working group have been adequately informed about the problem, but have so far not suggested a suite of measurements that are required. At this point, a redesign of the Band 3 cartridge is unlikely, appropriate quantification should suffice." Perhaps someone at the Science IPT can specify to what level we need to know the actual gain compression? For at least some of the bands, I suspect that the level of compression will depend on the operating (bias) point of the mixer. If so, then it seems to me that we will need a way to measure this quantity in the antenna, as we are unlikely to forever use the same operating point as measured in the FEICs.
  3. Configuration change. New configuration files from Sawada are attached and will be incorporated into the CASA simulator in the imminent release.
  4. Development. As part of the NA proposal to fund ALMA Operations we are required to submit a Strawman development program which meets the guidance funding and which might be completed in the 2012-2015 years.
  5. Operations Plan Version E. Meetings of the SciOps group continue aiming at producing VerE in February. Various scenarios for streamlining costs were proposed.
    1. One which might be discussed is 'What would the science impact be if ALMA were to move through a subset of its 28+ configurations?' Considerable savings in transporter crews might be made.
      • It has been suggested that only moving the array through a subset of configurations may save personnel costs, by eliminating one transporter crew. An investigation by Rob Reid suggests a configuration could emulate its immediate neighbors without sacrificing much sensitivity, but stretching it two configurations away would be more serious. If the moves were cut to 12-15, or skipping one configuration (and perhaps alternating on the inward cycle) the investigation suggests little loss. Larger savings could be realized by, for example, moving through fewer configurations--perhaps say eight in one direction, with moves in the other direction chosen to move through complementary arrays.
    2. Should there be a shutdown for the 'Alitplanic Winter'?
      • It has been proposed that the array might be shut down during the Jan-Feb 'Bolivian Winter' in order to save costs. Transparency for median, 25% and 75% conditions may be seen here. The most recent writeup is ALMA Memo 512, which shows a comparison of data from 1973 to 2005. Site characterization studies were discontinued in 2005, but Radford has continued his studies. Note that opacity during this period may be as high as 0.3 at 225 GHz, which translates to about 6mm of PWV but that in some years it is better; the El Nino pattern may have similar substantial effects on opacity during other parts of the year. The phase statistics show less variation. Although submm operation may be difficult for much of the period, operation at mm wavelengths is still quite practical.
  6. We need to implement automatic control of the focus on the antennas and take care of the resulting effects on pointing and path length. This is quite a complicated subject. The current draft of the design / requirements document is at Focus control: (pdf). Comments would be very welcome.

Jeff Mangum -- Calibration

  • See discussion on gain compression above. Measurement will be a function of frequency and tuning settings. There is an interesting discussion of methods of measurement in the link above.
  • Temporary weather station readout here.
  • Procurement of a temperature profiler for ALMA based on radiometric sounding of the O2 lines under way.

Bojan Nikolic/John Richer -- WVRs

  • Version 7 of the software has been rolled out, WVR data are now written out to ASDM to filled through to Measurement Sets and are readable in CASA
  • First data with 3 antennas, all equipped with WVRs, were taken 4th January
  • A lunchtime talk on the WVRs and phase correction given at NRAO/Charlottesville: http://www.mrao.cam.ac.uk/~bn204/publications/2010/2010JanNRAO.pdf

Lars-Ake Nyman -- AOP and Operations Software

  • AOP update:
    • Documents on cost issues and savings are discussed with ABC (ALMA Budget Committee)
    • The text in the AOP is being updated
    • Weekly telecons
  • The Operations Software Coordination Group (OSCG)started to meet

Wootten, Mauersberger, Sawada -- Site Characterization

Remijan, Markwick -- Splatalogue

  • In the last month, a Simple Line Access Protocol (SLAP) service was implemented to access the database structure we have for Splatalogue. Ray Plante from the IVOA was able to get a prototype going that returns an XML VO table. For example, try:

http://voera.ncsa.uiuc.edu:8080/splat-slap/slap?REQUEST=queryData&WAVELENGTH=0.00260075/0.00260080

To see a human-readable version of the result, see this:

http://heasarc.gsfc.nasa.gov/vo/squery/query.sh?viewform=1&viewURL=http://voera.ncsa.uiuc.edu:8080/splat-slap/slap%3FREQUEST=queryData%26WAVELENGTH=0.00260075/0.00260080

Comments on the result are always welcome.

Now these examples are currently accessing a copy of the splatalogue database on a local server at NCSA. In addition, the Splatalogue specific code is in the publicly accessible NVO repository for now as a branch of the dalserver toolkit (see http://trac.us-vo.org/project/nvo/browser/dal/dalserver/branches/splat). I'm guessing at some point we would move this to a respository of our choosing, but Ray said they would be happy to host the code more formally in their repository.

One of the main projects left to do is hosting the SLAP service at each of the institutions planning on hosting a spectral line catalog service (NRAO, JPL and CDMS). For that Ray is working on a list of installation instructions that will make available to us via a wiki page on the NVO Trac. Once we have those instructions, we will each be able to host a SLAP service. This will then lead to the transparency we desire as well as to be seemless to a user who wants to use these databases...one small program will then be able to access all the SLAP services simultaneously. Brian Kent also developed a very simple php code that uses the VO standards and queries. See: http://www.cv.nrao.edu/php/bkent/slap/SLAPClient2.php. I also have planned for Paul Frieden, the splatalogue programmer, to work on a simple bit of code (most likely JAVA) both of which we are planning to put off the main splat webpage to illustrate how to access the DB via the VO and perform queries.

I (we) have some stuff left to do:

1. finish handling some corner cases required by the standard. Ray is working on this...meaning, what will happen if someone selects a freq range from 100 - 100 GHz? Will the whole thing come crashing down?

2. Tony will expand the main table to explicitly enter the quantities in the SSLDM for expanded use. Meaning populate fields for Jupper, Jlower, KaUpper, KaLower, etc...When this is done, I will send a new copy of the DB to JPL and KOLN.

3. Continue to discuss versioning and referencing issues. You will see in the service that there are no references except where the data came from...ie, Lovas/JPL/CDMS.

4. Fix any implementation issues - ongoing of course.

Science Corner:

  1. Extragalactic millimeter-wave sources in South Pole Telescope survey data: source counts, catalog, and statistics for an 87 square-degree field
  2. Probing high-redshift quasars with ALMA. I. Expected observables and potential number of sources Authors: Dominik R. G. Schleicher, Marco Spaans, Ralf S. Klessen

Calendar

  1. Next meeting is on Feb 17th (14:30 UT). Mar 17th 2010 for the following month.

Events of Interest

(see also Al's ALMA Biweekly Calendar)

2010
 
 
 
 
 
 
Day
Date
Time
Event
location
details
 
 
Jan 18-21
 
Ops WG
Meeting
SCO
 
 
Jan 20
 
Sci IPT
telecon
 
 
 
Feb 17
 
Sci IPT
telecon
 
 
 
Mar 9-10
 
ASAC
F2F
 
 
 
Mar 17
 
Sci IPT
telecon
 
 

Upcoming Meetings

AAS 215, Washington 3-7 Jan, DC 'The largest astronomy meeting ever held.'

Astrobio 2010 13-15 Jan, Santiago

ESO Workshop on "The Origin and Fate of the Sun: Evolution of Solar-mass Stars Observed with High Angular Resolution", Garching, Germany, 2-5 March, 2010.

Astrobiology Science Conference 2010 April 26-29, 2010 League City, Texas

Synthesis Imaging School, June 8-15, Socorro.

ALMA-Herschel meeting November 17-19, ESO

Recent Meetings (presentations online)

From circumstellar disks to planetary systems Garching, 3-6 November 2009 talks online.

-- AlWootten - 2010-01-18
Topic attachments
I Attachment ActionSorted ascending Size Date Who Comment
Control_of_Antenna_Focus_-_Detailed_Requirements.pdfpdf Control_of_Antenna_Focus_-_Detailed_Requirements.pdf manage 157 K 2010-01-20 - 07:22 RichardHills Focus control
NAASC_NSF_proposal_ALMADevpt.pdfpdf NAASC_NSF_proposal_ALMADevpt.pdf manage 165 K 2010-01-20 - 08:50 AlWootten DRAFT of a STRAWMAN proposal which might be executed by one partner in early development.
Topic revision: r15 - 2010-08-02, ToddHunter
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