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Contact Information

• 2010-10-20 14:30 UT
  Note 'unusual' 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: 1-203-480-8549
  
• USA Toll Free Number: 866-600-8836
  
• Passcode: 3283890
  
• Leader: Hills, Wootten, Testi, Saito
  
• Attendees:

Topics

1 Old Business The enhanced Agenda from the last meeting is available. Science IPT notes from the last telecon are not available.

Eight ALMA antennas in operation at the AOS, seen in this photo from J. Zivick 2010 September 28. l-r DV08, DV03, DV04, DV07, DV02, DV05, DV06, PM02 where DV denotes Vertex antennas and PM Mistubishi antennas. Image courtesy ALMA (ESO/NAOJ/NRAO).

See other images and animations.

1. New Business--Project news/updates.(Hills, Peck)
   • For a recent summary see September 2010 Science Report
   • Previous reports for the project as a whole are at ALMA Monthly Reports.
   • See : PMCS Science Milestone Report 5 Oct 2010 for 'the big picture'. Infrastructure instability continues but seems to be improving.
   • As seen above, eight antennas were available after a move of DV08 to the AOS at pad T703. The array now consists of DV02 in pad J504; PM02 in pad T701; DV03 in pad N605; DV04 in pad T702; DV05 in pad J505; DV06 in pad T704; DV07 in pad J510; DV08 in pad T703. We are calling this the "Initial Commissioning Array" configuration. This allows good tests of e.g. antenna performance at different elevations. We expect to have 9 antennas later in the year; 16 by mid-April.
2. Change Requests and other technical items.
   • 260. Relaxation of the Band 3 polarization efficiency specification
     • CRE Number : ALMA-40.02.03.00-0662-A-CRE
     • Description :Relaxation is sought to the FE Requirement [FEND-40.00.00.00-00226-00 / AT] which requires that the polarization efficiency of the tertiary optics system shall exceed 99.5% for all ten bands. The proposed relaxed requirement (for Band 3 only) is 98% (-17 dB cross polarization in the integrated sense.) The peak cross polarization for the cold cartridge alone (without warm optics), [FEND-40.02.03.00-00298-00 / T], is sought to be relaxed to -19 dB instead of the presently specified -23 dB.
     • This request is instigated due to two factors: (i) several FE assemblies have been measured at the integration centers at this level of cross polarization for Band 3, and this represents the limit of achievable/measureable performance. (ii) The Band 3 cartridge group is unable to meet their originally specified cross polarization requirement (for the cold cartridge alone, without warm optics), due to manufacturability/yield concerns.
     • Note that, the cross polarization requirements for the Band 3 "cold cartridge alone" (without warm optics) are specified in terms of peak cross polarization performance (and not in the integrated cross polarization performance sense that the completed FE assembly is eventually evaluated against). This metric was chosen (somewhat arbitrarily) and meeting or failing this criteria at -23 dB peak cross polarization level does not guarantee compliance to the formal FE specifications one way or the other. This metric was chosen because integrating over the entire beam scan area (again without the warm optics) was thought to under estimate the cross polarization efficiency.
     • Statistics collected for the Band 3 cartridges produced thus far indicate that about 50% of the cartridges have a cross polarization performance (in the peak sense, on at least one polarization/test frequency combination) that is poorer that -23 dB with respect to the peak of the co-polarization pattern.
   • 258. Comments are available at the link from CRE 258. See also discussion at CSV-463. Change Several Requirements Applied to the Back End Antenna Article CRE Number : ALMA-50.00.00.00-401-A-CRE. Summary:
     • a) Change the requirement for VSWR from ≤ 1.4 to ≤ 1.8 in Section 3.1.1 of the ICD between the Front End and Back End IF Processor (ALMA-40.08.00.00-52.00.00.00-A-ICD).
     • b) Change requirement 272 from ≤ 3 dB to ≤ 4.9 dB gain variation (pk-pk) across a baseband channel (2 - 4 GHz) allocated to Back End (Antenna Article) in ALMA System Technical Requirements for the 12m Array (ALMA-80.04.00.00-005-B-SPE). Also change the passband gain variation requirement 02720 in Technical Requirements for the Back End Subsystem (ALMA-50.00.00.00-092-B-SPE) allocated to the IF Processor (IFP) from ≤ 2.7 dB pk-pk to ≤ 3.7 dB pk-pk and allocated to the Data Transmitter (DTX) (digitizer) from ≤ 1 dB pk-pk to ≤ 1.2 dB pk-pk.
   • Source on Chajnantor. Here is a Requirements_for_an_Artificial_Source.pdf note on the requirements for an Artificial Source to do holography and polarization calibration measurements. This has been talked about for some time but interest has been renewed as a result of the investigations of the surface errors on the antennas. To track the surface on the other antennas we need to do a lot more high-resolution holography at the high site. This source is proposed as a way of making this practical using the astronomical receivers. The holography side is straight-forward but we need help in understanding the polarization requirements.
3. Employment
   • JAO DSO Support Astronomer positions. Proposal Handling Team Lead interviews scheduled.
   • ESO:
   • NRAO: Advertisement for postdoctoral positions will appear in AAS Newsletter soon
   • NAOJ: Advertisement for postdoctoral positions will appear in AAS job register on Nov 1st.
4. Astronomer Outreach: ALMA News. JAO ALMA Webpages. JAONewsletter No 6. NRAO eNews ESO Newsletter No 16 NAOJ News. NRAO ALMA Calendar
5. Current SYSE-80.04.01.00-004-Q-DWG.pdf: ALMA System Diagram Rev Q
   1. Current IPS attached
6. Directories
   • (old) ALMA Chile Directory. The directory is online at alma.cl from within the project.

Project Scientists

1. North America
2. Europe
3. East Asia
   • ALMA-Subaru Science Workshop held on Sep 29th- Oct 1st in Mitaka including ALMA OT demo.
   • First announcement of 2nd ALMA-J Users meeting held on 13-14th Jan. 2011.

1. ASAC Report, Board Meeting

Jeff Mangum -- Calibration

• Temporary weather station readout here.
• Satellite images of water vapor at Chajnantor.
• Forecasts of Meteorological Conditions at Chajnantor

Bojan Nikolic/John Richer -- WVRs

• Presentation at the EU FP6 ALMA Enhancement Annual Meeting on WVR phase correction: http://www.mrao.cam.ac.uk/~bn204/publications/2010/2010-10-14-Annual.pdf
• Oxygen sounder: People with access to the ALMA network can view the latest measured temperature profile at http://10.195.17.192:8080/latest

Lars-Ake Nyman -- eSSR

• SciOps Review

Wootten -- Site Characterization

1. * 2010-10-11-ALMA-20.01.04.00-90.05.13.00-D-ICD.pdf: Draft ICD Site-Science Ancillary Equipment from C. Janes. Update to former document proposed.

Science Corner

Calendar

1. Next meeting is on Nov 17th (14:30 UT). Dec 15th 2010 for the following month.

Events of Interest

(see also Al's ALMA Monthly/Biweekly Calendar)

2010
Day	Date	Time	Event	location	details
	Oct 7-8		CSV Status Update	Chile
	Oct 11-12		SciOps Readiness Review	Chile
	Oct 13-14		ASAC f2f		Santiago
	Oct 20		Sci IPT	telecon
	Oct 25-28		Annual ALMA External Review	Chile
	Nov 10		Observatory Readiness Review	Chile
	Nov 17		Sci IPT	telecon
	Nov 16-18		ALMA Board Meeting	Chile
	Nov 22		Date for decision on ES	Chile
	Dec 15		Sci IPT	telecon

Upcoming Meetings

Stormy Cosmos: The Evolving Interstellar Medium: Recent Progress from Space IR/Submm 1 - 4 November 2010 Pasadena, CA Hosted by the NASA Herschel Science Center, Spitzer Science Center

The Impact of Herschel Surveys on ALMA Early Science Garching, November 17-19, 2010

Observing with ALMA--Early Science IRAM, 29 Nov - 1 Dec 2010

217th AAS Seattle, WA Observing with ALMA - Special Session- January 12, 2011 2:00 PM

15-17 Jan 2011 Workshop ALMA: Extending the Limits of Astrophysical Spectroscopy in Victoria

The Molecular Universe May 30 - June 3, 2011 Toledo, Spain

-- AlWootten - 2010-10-19

• Science_-_September_2010.pdf: September 2010 Science Report

• Science_Milestones_05Oct2010.pdf: PMCS Science Milestone Report 5 Oct 2010

• Requirements_for_an_Artificial_Source.pdf: Requirements for artificial source on chajnantor

• 2010-10-11-ALMA-20.01.04.00-90.05.13.00-D-ICD.pdf: Draft ICD Site-Science Ancillary Equipment