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Contact Information

  • 2005-8-17 14:30 UT
  • Duration: 1 hr
  • USA Toll Free Number: 877-874-1919
  • Toll Number: +1-203-320-9891
  • Passcode: 185064
  • Leader: Al Wootten


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

DUSTY04 collection of papers relevant to ALMA.

  1. New Business--Project news/updates (Wootten, Wilson, Kawabe)

  1. Milestones
  2. Subarrays-- 1 Subarrays -- An option has arisen whereby the patch panel could accommodate any or all of the antennas available. See Subarray Wiki
  3. Nutator Science Requirements. Finalize the Nutator almaedm requirements by 15 August.
  4. RFMembrane Science Requirements are being developed.
  5. Early Science Modes: Originally the plan was to implement only modes which were available on the single baseline correlator at the ATF on the ALMA correlator in Chile. However, the tunable filter bank will almost certainly be implemented on the Chilean correlator, though not at the ATF. Therefore we need to define modes which we would like to have available both for testing and for observing in the early phases of Chilean operations. Please see the document Baseline Correlator + TFB Specs for details. One possibility is a wideband mode for e.g. continuum simultaneous with a narrowband mode for e.g. a spectral line. See ALMA Early Science Modes SCID-
  • We should implement at least a mode with polarization cross products.
  • With few antennas, every bit of sensitivity could count. I favor at least one mode with four bit sampling.
  • Maximum continuum sensitivity suggests implementing the widest mode, which does not provide four bit sampling. Best velocity resolution for full polzn is only 1.28 km/s@230 GHz, which is not sufficient for molecular cloud work. The latter needs at least .3, better .15km/s sampling.

The following should cover most bases:
>Full polzn
>Number of sub-channel filters   Total Bandwidth   Number of Spectral Points   Spectral Resolution   Velocity resolution at 230 GHz   Correlation   Sample Factor   Sensitivity*
>32   2 GHz   2048   976 kHz   1.28 km/s   2-bit x 2-bit   Nyquist   0.88
>1   62.5 MHz   2048     30 kHz   0.04 km/s   2-bit x 2-bit   Nyquist   0.88
>1   62.5 MHz   1024     61 kHz   0.08 km/s   2-bit x 2-bit   Twice Nyquist   0.94
>1   62.5 MHz   512    122 kHz   0.16 km/s   4-bit x 4-bit   Nyquist   0.99
>1   62.5 MHz   256    244 kHz   0.32 km/s   4-bit x 4-bit   Twice Nyquist   0.99
>Time Division Mode   2 GHz   64   31.25 MHz   40.8 km/s   2-bit x 2-bit   Nyquist   0.88
>no cross polzn, two baseband.
>32   2 GHz   4096   488 kHz   0.64 km/s   2-bit x 2-bit   Nyquist   0.88
>1   62.5 MHz   4096     15 kHz   0.02 km/s   2-bit x 2-bit   Nyquist   0.88
>1   62.5 MHz   2048     30 kHz   0.04 km/s   2-bit x 2-bit   Twice Nyquist   0.94
>1   62.5 MHz   1024     61 kHz   0.08 km/s   4-bit x 4-bit   Nyquist   0.99
>1   62.5 MHz   512    122 kHz   0.16 km/s   4-bit x 4-bit   Twice Nyquist   0.99
>Time Division Mode   2 GHz   128   15.6 MHz   20.4 km/s   2-bit x 2-bit   Nyquist   0.88
  1. Group Activities (all)
  2. Next meeting is on Sept 14th (14:00 UT)

Science IPT Group Activity Reports

Please include your Group Activity Report here (How to Enter Your Report), or email it to AlWootten

1 Science IPT -
  • Rebaselining Options.
  • New Charges to ASAC
  • ALMA Cost Review forced postponement of JAO/IPT activities, ACA system review.

2 ASAC news

3 Astronomer Outreach: NRAO Newsletter ESO Newsletter. NRAO ALMA Calendar

4 Sci 05Q2 Report

5 I have a Science IPT Directory but cannot upload owing to NRAO security.

Emerson/Laing/Vila-Vilaro -- Instrument Scientists

  • B4, B8 PDR: Kawabe-san reports that the "Band-4 and Band-8 PDRs we had last month in Japan were very successful. Qualification model for each band meets ALMA Specification." These models use a conventional wire grid to separate polarizations. However, an ortho-mode transducer could achieve much smaller beam squint. Sekimoto-san, a leader of the B8 team, and Kawabe-san support parallel development of the OMT owing to its scientific benefits.
  • Front End Delta-PDR:
  • System Requirmenets Review:

Conway, Holdaway -- New Configuration

  • Site team identified a few problem areas; repositioning of pads is under refinement.
  • John writes: "You can download here. The draft document ALMA- specifying the positions and configuration occupation schemes for the inner 151 pads of ALMA. This document includes the changes proposed by the recent ground-truth survey at the site led by Angel Otarola. After discussion with management it was thought best to submit a document now covering the inner 151 pads, and wait till a later document to define the approx 35 pads of the Y+ array. If there are no comments on this document I intend to submit this document (after fixing any typos) to ALMAEDM."

Jeff Mangum -- Calibration

Robert Lucas -- SSR

  • There was no SSR meeting during July... but there was one in August (2005-08-10)
    • The new Japanese members/subsystem scientists are: Toshihiro Handa(obs.Prep., Scheduling), Munetake Momose (ACA, Tel.Cal.), Masatoshi Ohishi (Pipeline, Off-Line)
    • Debra Shepherd will progressively move her focus to coordination of software commissioning at the ATF (she continues as Offline subsystem scientist however).
    • SSR to include optical pointing as an observing mode
    • SSR and Use Cases document being updated for ACA.
    • Face to Face Meeting in Charlottesville next fall (2005-11-20/21)

Michiel Hogerheijde -- DRSP

  • There still are two new DRSP projects under consideration: one is being revised and a second one is being reviewed. New projects are welcome at any time! Bally and Williams will work on one centering on proplyds.

Robert Laing -- Commissioning and Science Verification

Mark Holdaway/Steve Myers -- Imaging

L.-A. Nyman -- Site Characterization

The goals Angel, Alison, Roberto, Juan, Jorge and Vicente achieved in this campaign are given in the following report from Angel:

1) Roberto managed successfully to replace the NRAO battery bank with new ones. The best of the old batteries were used to arrange a better battery bank for the radiosonde equipment.

2) Removal of the stakes indicating the position of the previous spiral configuration. We also removed two of the stakes of the old Y+ configuration. I gave Roberto a list of 41 coordinates for the stakes to be removed in the Y+ configuration. This operation might need another two days of work in the neareast future.

3) Staking of the spiral configuration. The compact configuration was not staked out because the accuracy of the GPS positioning is not good enough for locating the pads keeping a +/- 5 cm accuracy for the distance between them. The survey group will have no problems to locate the position of all these pads because they fall within a small area.

4) We also gathered energy flux data at Chajnantor (5000 m) and a site at 4500 m just east from Co Negro and west from Chajnantor using equipment Alison borrowed from the University of Reading in the UK.

5) We launched a total of 35 radiosondes covering night time, dawn, daytime and dusk. We used exclusively AIR-5A sondes and despite our efforts we couldn't make the radiosonde equipment work with RS-80 Vaisala sondes. We are now in contact with Simon Radford and Bryan Butler for ideas. Making the system work with Vaisala sondes is especially important because the Air-5A sondes are no longer produced and we have used all the ones available at the site.

6) With the collaboration of the survey engineer Mr. Emilio Pacheco we managed to measured the accuracy of the north-sout orientation as monumented at the site. After a quick look at the measurements performed by Mr. Pacheco I obtained an accuracy of about 1.5' (I will calculate all the stars positions used for this verification once I am back in Tucson).

7) Roberto and I talked about the procedure to perform a calibration of the existing water vapour radiometers. This procedure consists of using a liquid nitrogen load to verify the temperature of the hot and warm calibration loads. The last calibration was performed -I believe- in 1999 so I think would be good to repeat the measurements. For this calibration we need liquid nitrogen, our neighbors from APEX do use LN2 but unfortunately they didn't have it available at this time. It would be great if Roberto can borrow some LN2 in the future (a couple of liters) to perfom the radiometers calibration.

Science Corner:

ALMA and Cosmology


Official JAO Calendar New!!

ALMA Events of Interest

(see also Al's ALMA Biweekly Calendar)

Day Date Time Event location details
Aug 25
All Day
Amplitude Calibration Review
August 26
2-3pm EDT
ANASAC Telecon
877-874-1919 PC=185064
Sep 7
1500 UT
ASAC Telecon
Sep 22
ALMA Board telecon
Oct 1-2
all day
ASAC Face-to-Face Meeting
Oct 6
Rolling Stones Concert
Scott Stadium, Charlottesville
October 28
2-3pm EDT
ANASAC Telecon
877-874-1919 PC=185064
Nov 1-2
ALMA Board Meeting
Dec 8
ALMA Board telecon
2 days
SSR Meeting

Upcoming Meetings

IAU Symposium 227 Massive Star Birth: A Crossroads of Astrophysics May 16-20 2005, Acireale, Italy

Astrobiology and the Origins of Life Hamilton, Ontario, Canada May 24-28.

Workshop on submillimeter wavelength astronomy in Cambridge (JUN 13-16).

Star Formation in the Era of Three Great Observatories July 13-15, 2005 in Cambridge, Massachusetts

Astrochemistry throughout the Universe: Recent Successes and Current Challenges 2005 August 29 - September 2; Asilomar, California

Galactic and Extragalactic ISM Modelling in an ALMA Perspective October 13-15 2005 Onsala, Sweden.

Protostars and Planets V 24 - 28 October 2005 Hilton Waikoloa Village, The Big Island, Hawaii

Mm/submm Techniques and Science session, at the URSI General Assembly 2005 October 23-29, New Delhi, India

"IR Diagnostics of Galaxy Evolution". 14-16 November 2005, Pasadena, CA

50th anniversary of the founding of NRAO October 15-19, 2006; Charlottesville, Virginia

ALMA November 13-16; Madrid, Spain

See also NAASC listing

-- AlWootten - 13 Aug 2005
Topic revision: r9 - 2013-05-21, JeffMangum
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