Teleconference,
2 May 2002
Draft
Minutes
Participants:
R. Bachiller, A. Benz, L. Bronfman, R. Brown, P. Cox, R. Crutcher, N. Evans, S.
Guilloteau, M. Gurwell, T. Hasegawa, M. Ishiguro, R. Kurz, J. Mangum, D.
Mardones, M. Rafal, J. Richer, P. Schilke, P. Shaver, E. van Dishoeck, M.
Walmsley, D. Wilner, A. Wootten, S. Yamamoto
The
proposed agenda
was adopted, and the minutes of the March face-to-face meeting and the April
teleconference were accepted.
Possible
dates for the next face-to-face meeting were discussed. Options D (15-18
September) and E (6-9 September) are being kept open (D is favoured), but
potential conflicts have to be cleared and a decision will be made this month.
1)
Project
status and report from the Venice ACC meeting
R.
Kurz reported on the most important decisions made at the ACC meeting:
a)
The
ACC will be replaced on 1 June by an ALMA Board; Europe and North America will
each have one agency representative, one executive representative, and at least
two representatives from the community.
b)
Recruitment
for the Joint ALMA Office will proceed as rapidly as possible, with
announcements within 1-2 months for the positions of Project Director, Project
Manager, and Project Scientist. The process should be completed within 9-12
months. Meanwhile, an interim Joint ALMA Office will be set up, with interim
appointments for the above positions (and possibly Project Engineer) to be made
by 1 June.
c)
The
AEC project plan was accepted, subject to some minor modifications. The revised
plan will be submitted to the ACC for final approval at its 21 May
teleconference.
Progress
is also being made with the issues in Chile. R. Brown said that the changes in
the management structure were very important and represented major progress
toward a more integrated project. Finally, R. Kurz announced that R.
Eisenstein will be leaving his position
at the NSF in June.
2)
Reports
from the ALMA week (Granada April 22/26)
Summary
reports were given of the various parallel sessions at the ALMA week in
Granada; full reports are being prepared by the teams. Concerning the front
ends, S. Guilloteau reported a major reorganization: W. Wild is leaving as team
leader, and C. Cunningham will serve as acting team leader. The overall
schedule is a serious issue. Another major issue is that the photonics
development is not advancing fast enough, and the baseline LO option will
likely be implemented. Other critical items include band 6, and the
implementation of optics for the WVR.
J.
Mangum summarized the calibration sessions. A Calibration Group is being
formed; there is already a draft list of potential members, and the next step
is to appoint a leader of the group. J. Mangum mentioned that modifications are
required in the Project Book on calibration. There were reports on various
calibration techniques: the apex radiator, the dual-load system, the
semi-transparent vane system, and the Cambridge-Onsala phase calibration
technique. Very good progress has been made on atmospheric radiometry
calibration; the effective temperature of the atmosphere can be determined to a
few percent accuracy with the new
version of the ATM program developed by J. R. Pardo and J. Cernicharo. R.
Crutcher asked about polarization calibration. J. Mangum reported that it is in
the requirements, but was not discussed in detail at the meeting. S. Guilloteau
mentioned a new memo and a change request in the Project Book concerning the
limitations of the dual-load system at submillimeter wavelengths.
On
photonics, A. Wootten said that progress is being made; there is enough power
from the laser, but excess noise. An optical filter may be used to suppress RIN
noise and will soon be tested in Tucson. However it may be necessary remain
with the baseline plan: photonics to 100 GHz, multipliers at higher
frequencies.
A.
Wootten also reported on the configuration meetings. There is a memo on the Y+
configuration, which is looking good. A decision is needed between the Y+ or
the ring around Chascon for the long baselines (the ring is more difficult
because of terrain, but gives somewhat better resolution). Work continues on
the smaller configurations. L. Bronfman commented that the Y+ configuration
requires antennas to the west of the ALMA reserve, and this raises questions
about the shared vs. exclusive areas. S. Guilloteau said that a decision by the
ASAC will be needed on the configuration issue.
J.
Richer summarized the software and SSR sessions. The ASAC concept of a “core
program” generated interest, as there are differences from the current
development plan. The group is recruiting subsystem project scientists in 10
areas, and developing a detailed management plan which will be ready by the
time of the September ASAC meeting. P. Cox said that the Operations Group would
have to give more consideration to the “stringency” concept, and communicate
with the SSR group.
R.
Bachiller reported on the backend sessions, which contained the only PDR held
during the ALMA week. He said that this area is going well, and there is no
important technical risk (the only problem area is the photonics laser
oscillator). A final report on the PDR will be available in a few weeks and a
prototype (end-to-end) will be ready by Fall 2003.
3)
ASAC
Charge
P.
Cox reported that the ACC has expressed
concern about the relative independence of the ASAC, and that the ACC intends
to give stronger direction in the future, including more specific charges. A.
Wootten said that the final version of the ASAC charter is now on the web. To a
question by N. Evans, it was replied that the ACC had not made any comments on
the TAC process discussed in the ASAC report.
4)
Next
teleconference
The
next ASAC teleconference will take place on Wednesday 5 June at 14:30 UT.