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Contact Information

• 2008-5-28 14:30 UT Please check your local time; it may have changed!
• Note: C. Wilson points out line noise may be muted by pressing *6 which works thru the call center.
• Duration: 1 hr
• USA Toll Free Number: 877-874-1919
• Toll Number: +1-203-320-9891
• Passcode: 185064
• Leader: Al Wootten
• Attendees:

Topics

1. Old Business The enhanced Agenda from last meeting is available. Science IPT notes from last month's telecon are attached to the bottom of the agenda.

Interferometric spectrum of Orion from ATF, reduced in CASA.

See other images and animations. See other images and transporters.

1. New Business--Project news/updates (Hills, Peck)

• ALMA Status Report (From R. Hills to ASAC).
• ASAC Matters.
  • Response to Report
  • New Charges
  • Blain becomes ASAC Chair; Meeting in Charlottesville 28-29 September 2008.
• Band 10 Report The atmospheric transmission during best octile (stringency = 8) conditions at Chajnantor over the ALMA Band 10 window (787-950 GHz) is shown. Some important lines mentioned in the ASAC Enhancement report (Sept 2001) on Band 10 are flagged. Additionally, the ASAC mentioned the scientific utility of this window for Redshifted [C II] emission and also for dust emission . Redshifted [C II] can, of course, cover this band for z=1 - 1.4, a critical period in the evolution of galaxies toward their present form. The band is clearest in its center, of course, which makes that the best frequency locale for dust measurements. Please see Attachment at bottom of agenda
• Band 7 Cross polarization performance status. (See attached report below).
• Extended configuration status
• ACA Correlator -- a single subarray (Peck)
• Quarter Wave plate requirements
• ALMA Science IPT wiki page
• Astronomer Outreach: ESO Newsletter New ESO Messenger with WVR Correction article, New NRAO Newsletter ALMA News. NAOJ News. NRAO ALMA Calendar
  • Current ALMA System Block Diagram Vers O.

1. Directories
   • Science IPT Directory Contributors to ALMA Science IPT (Sept06).
   • ALMA Directory ALMA Directory v3.0
   • ALMA Chile Directory.

Science IPT Group Activity Reports

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

Project Scientists

1. Science IPT - Follow up from last meeting
   • Change Control Board items, other technical concerns (Hills)
     • Discussion on cartridge availability in front ends. (Hills)
     • Polarization. See discussion items circulated by Hills.
     • LO Phase lock bandwidth. CRE 179 proposes reducing this which should reduce phase noise at the highest frequencies but lose a little efficiency from the lag when phase switching.
     • Line Stretcher Compensation Is it really necessary to use a closed-loop servo to compensate for the line-length changes or would it be sufficient to simply measure the changes and correct them all in software - either by adjusting the LO phase or in the data reduction? Follow link to attachment please for discussion.
     • Acceleration of the 7m ACA antennas. CRE 184 proposes reducing the maximum accelerations and demonstrates that the loss of observing efficiency will be small. See table at Jan 2007 discussion.
     • Here Draft Front End Pointing CRE is a first version of a change request aimed at ensuring that the any pointing errors arising due to deflections in the front end are small. Differential movements between the receivers would be particularly damaging to offset pointing.
     • QuarterwavePlates are suggested for B7. A proposed specification is among FE IPT documents. We proposed these to begin a dialog with FE in July 2006. At that time there was a f2f meeting with FE and Sci here in Cville. A reply was posted to edm 14 months later calling for review and approval of these specifications; I am unaware that this was discussed in a science or cal group meeting. Let us proceed: is the proposed bandwidth and center agreed? How accurately does it need to be a quarter wave? A memo on the SMA device is attached at the bottom of the agenda for last month.
   • ATF: (Peck)
     • Summary. ATF lifetime to be extended thru 1 Sept, if no mishaps.
     • Goals: (1) Get software working (2) Training personnel and developing procedures
     • Spectral-line pointing needs to be available in Q1 2008 for single dish testing in Chile.
     • The current schedule is below. Please let Alison and Debra know if anyone has any issues with this. During the current period foci of interest include further understanding of the behavior of the Line Length Corrector, to measure the baseline correctly and to begin interferometric pointing.

Week	Event
2008

• OSF

2008
Week	Event
Jun ?	Emerson VxRSI antenna contractor handover testing begins 4 Feb

1. Next meeting is on June 21st (14:30 UT). June 18th for the following month.
2. Astronomer Outreach: New ESO ALMA Webpages. http://www.nrao.edu/news/newsletters/][NRAO Newsletter]]. NAOJ News. NRAO ALMA Calendar

Emerson/Laing/Vila-Vilaro -- Instrument Scientists

• Phase jump across scan boundaries. We discovered at the ATF that the phase is reset at scan boundaries, as there is no requirement to maintain it. Q: Should this be a requirement? (Emerson)
• Sci IPT at the ATF Checklists, Progress Reports.
• CIPT Wiki Daily ATF reports.

Richard Hills, Alison Peck, Robert Laing -- Commissioning and Science Verification

• Commissioning and Science Verification
  • Plan.

Holdaway, Reid -- Configuration Group

• ExtendedConfiguration Work
  • Holdaway's description of the development of the design for the extended ALMA configurations, rev 2 for edm.
• Revision to YPlus array by Holdaway for comment.
• Final configuration design. We continue to assess performance - see imaging, below, and possible improvements. Some initial results from Holdaway's recent study are attached to that link.
• The uv error amplitudes after CLEANing a simulated noiseless 4h observation of an HII region with out26 and its reoptimized version.
• http://www.cv.nrao.edu/~rreid/telesims/cfgeval has been created as a repository of miscellaneous configuration evaluation items.

Steve Myers/Rob Reid (Mark Holdaway)-- Imaging

• A set of ALMA PSFs with varying amounts of robust weighting has been made and summarized in weighting.html. It will be useful for determining how much Briggs weighting to use when, but the most immediately interesting result is that it should be possible to use any resolution in the ALMA range with only a litte reweighting: . The set is being extended with tapered beams.
• CASA Simulator Report
  • The Library of standard ALMA images for simulation is available.
  • Fidelities over 10⁴ have been achieved for 4 hour noiseless "observations" of the M31 HII region, using deep cleans with a tightly constrained support region.
  • CASA simulation wiki with examples
  • Bojan Nikolic is using the simulator to make u-v data and maps when investigating the effects of atmospheric phase and, in the future, for trying out phase-correction techniques.
• Pointing selfcalibration for mosaics

Jeff Mangum -- Calibration

• Response to ASAC comments
• Pointing Design document now drafted.
• Calibration Plan: Current version of the calibration plan and associated documents ("examples", "roadmaps", "matrices", etc.) posted. Comments welcome.
• Calibration Examples: The "meat" of the Calibration Plan. Review of these documents nearly complete, some need updates.
• Ancillary Calibration Devices: Documents which describe the weather station and temperature profile technical specifications have been developed. Initial purchase documentation for (P,T,RH,Ws,Wdir) measurement devices has been made by Leonardo.

Robert Lucas -- SSR

• Latest SSR meeting (2008-04-09).
• Testing of integrated system at the ATF, using data in ASDM format.
• Testing of TelCal: phase measurement, delay measurement, phase curve .
• ACA Correlator integration work continued

Michiel Hogerheijde -- DRSP

• No progress on including the author responses to the referee comments, the DRSP 2.0 web site continues to be password protected. If you would like access (keeping in mind that the author responses have not been added yet) use: username=review and password=chajnantor! (including the exclamation mark).

L.-A. Nyman -- Site Characterization

• OSF Weather Station link.
• APEX Weather Station link.

Remijan, Markwick-Kemper -- ALMA Working Group on Spectral Line Frequencies

• ALMA White Paper on Lab Astrophysics was sent to Al and Andrew on Dec 1, 2007 - Click for a COPY . It includes a summary of:
  • NASA Laboratory Astrophysics Workshop White Paper
  • Workshop on Submillimeter and Far-Infrared Laboratory Spectroscopy in Support of Herschel, SOFIA, and ALMA Report
• Splatalogue.net is the home for Splatalogue and has been updated with the newest database and user interface. This is the "beta" release we anticipated for this year. We are in the process of continuing to debug the user interface as well as updating the database. Paul Frieden, a programmer from Illinois, has joined the efforts and is making a substantial contribution to the user interface. Splatalogue was presented at the AAS in Austin and will be presented in a formal presentation at the Ohio State Molecular Spectroscopy Meeting in June.

Science Corner:

The properties of powerful radio sources at 90 GHz Authors: M. J. Hardcastle, L. W. Looney Discussion of ALMA contribution to radio galaxy astrophysics.

Calendar

Events of Interest

(see also Al's ALMA Biweekly Calendar)

2008
Day	Date	Time	Event	location	details
	May 15		ALMA Board	Telecon
	May 21	2200UT	ASAC	Telecon
	May 28-29		1st LO and WCA Manufacturing Readiness Review	Charlottesville
	June 16-18		Master Laser, Laser Synthesizer CDR	Teraxion
	July 2	1430UT	ASAC	Telecon
	July 17		ALMA Board	Telecon
	Sep 3	1430UT	ASAC	Telecon
	Sep 28-29		ASAC face-to-face	Charlottesville
	Dec 9-11		ALMA Annual External Incremental Review	OSF

Upcoming Meetings

URSI General Assembly Aug 7-16, Chicago

Transformational Science with ALMA: The Birth and Feedback of Massive Stars, Within and Beyond the Galaxy Sep 25-27, Charlottesville.

See ALMA related meetings.

-- AlWootten - 27 May 2008 * Band10.pdf: Band10.pdf

* Configurations_update.pdf: Configurations_update.pdf

* Configurations_update.pdf: Good copy

* Band10.pdf: Good copy