MMA Imaging and Calibration Group

Agenda for meeting Tuesday, 16 May 2000 at 4pm EDT.

Date: 16 May 2000

Time: 4:00 pm EDT (2:00 pm Socorro, 1:00 pm Tucson)

Phone: (804)296-7082 (CV SoundStation Premier Conference phone).

Past minutes, etc on MMA Imaging and Calibration Division Page

Minutes

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News. -Wootten

A New Project Book is available for ALMA. Other news from other groups at the joint DG meeting:

Backend

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Europe: The 1st-generation digitizer (2GHz clock) will go to the foundry at the end of June.

It is important for the group to receive the IF downconverter specifications.

The minutes of the future correlator meeting held in April will be available soon.

US: Goal to have the 10-Gbps IF digital link working by end of summer.

Correlator

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CDL is proceeding with chip design. Continuing bench prototype experiments on the 0.18 micron Zylink chips. There will be an internal review of the FIR filter final layout.

SSR -Wootten, Glendenning, Mangum

Review discussion of Items for ASAC to consider.

Japan Involvement -Wootten

See Letter to ASAC from Bob Brown.

Configurations - Morita, Yun

Morita has conducted several simulations for single pointing imaging including antenna pointing errors.

He reports:

'Array configurations used in these simulations are a ring array and a spiral array which was modified from an original John's spiral array. A multi compact Gaussian model was used as a source model. In the case of no pointing error, results shows that we can obtain very high quality images with both arrays, although there are significant differences of image qualities depending on array configuraions and HA coverages. However, when I put some pointing errors, such differences disappears soon. For example, dynamic ranges of no pointing error cases are from 4,000 to 15,000 but from 2,000 to 3,000 for 1 arcsec pointing error and around 1,000 for 2.5 arcsec pointing error at 230 GHz (See attached figures).

	V1. First of Morita's figures.

	V2. Second of Morita's figures.

I am writing a short report and detailed explanation of these simulations will be appeared in the report.

These are preliminary results and I need more simulations using various configurations and source models. At the moment, however, the imaging simulation with pointing errors is limitted by CPU power so current pixel size of the model is 256 x 256. In the case of 1024 x 1024 pixel size and 64 antennas, it takes about 1 hour to calculate visilities for every integration by the most powerful CPU server at Nobeyama! So, unfortunately, I cannot use standard images in the library prepared by Min.'

These calculations are very interesting and we should proceed quickly with the simulation machine discussed in Tucson. I think we should have a goal of finishing a first round of simulations by the end of June and proceeding with AIPS++ simulations then, achieving results by July.

Action items from the March CoDR will be discussed.

Prototype Antenna, Calibration -Mangum

Upcoming Reviews: Test Interferometer plans, Antenna PDR (June 20-23). Mangum calibration protomemo. Any word from the meeting?

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Action Items 9May2000

DECISION: Configurations--where are we? Next phone meeting plans...

DECISION: Implementation of 183 GHz WVR?

DECISION: Are the specs for a nutating secondary correct?

DECISION: What is the total power specification on the ALMA?

DECISION: What is the effect of 1/f noise in the HEMT amplifiers of SIS receivers upon our ability to combine total power and interferometric images into a faithful representation of the sky?

Year 2000

January	February	March	April
May	June	July	August
September	October	November	December

May, 1-2	Site Development Discussions	Garching, Germany
May 15-17	Test Interferometer Planning	Tucson, Arizona

Jun, 12-16	2nd IRAM Millimeter Interferometry Summer School	IRAM Grenoble, France
June 19-20	Vertex Antenna PDR	Duisburg, Germany
Jun, 20-27	7th Synthesis Imaging Summer School	Socorro, USA
June 21-22	EIE Antenna PDR	Venice, Italy

October 13

ACC Meeting

Paris, France

Send comments to <tcontini@eso.org> Last modified: Tue Feb 22 09:55:07 MET

Travel

AW -> Socorro 20-25 May 2000 ------