THE STUC REPORT
==========
Subject: Final STUC report
Date: Thu, 26 Apr 2001 23:43:58 +0200
From: George Miley <miley@strw.leidenuniv.nl> (by way of George Miley
<miley@strw.leidenuniv.nl>)
To: beckwith@stsci.edu, david.s.leckrone.1@gsfc.nasa.gov
CC: macchetto@stsci.edu, marc@coma.berkeley.edu,
jsd@roe.ac.uk,elmegreen@vaxsar.vassar.edu,
ford@pha.jhu.edu,slh@pillan.astro.washington.edu,
cimpey@as.arizona.edu,kormendy@chandra.as.utexas.edu,
miley@strw.strw.leidenuniv.nl,sanders@galileo.ifa.hawaii.edu,
krs@exoplanet.jpl.nasa.gov,stocke@casa.colorado.edu, vidalmadjar@iap.fr
Dear Steve and Dave,
Here is the final version of the STUC report for the April 2001 meeting.
Many thanks for all the effort devoted to the meeting by the Institute
and Project staff. Below is an asci and attached a MSWord version.
Looking forward to seeing you at the next meeting in October.
Best wishes,
George
-----------------------------
SPACE TELESCOPE USERS COMMITTEE
REPORT - APRIL 2001
The Space Telescope Users Committee (STUC) met on 19th and 20th April
2001 in the Board Room of the Space Telescope Science Institute.
Attended: Debra Elmegreen, Holland Ford, Chris Impey, John Kormendy,
George Miley (Chair), Dave Sanders, Karl Stapelfeldt, Alfred Vidal-Madjar.
Unable to attend: Marc Davis, James Dunlop, Suzanne Hawley, John Stocke
1. GENERAL- STUC PORTFOLIOS
The composition of STUC changed substantially since the last STUC
meeting. The chairman welcomed 5 new members to the committee, James Dunlop,
Holland Ford, Karl Stapelfeldt, John Stocke and Alfred Vidal-Madjar, only 3 of
which were able to attend this meeting.
The following is a revised list of allocated portfolios:
(i) Instrumental Issues: (including observing modes, calibration, performance, capabilities and
upgrades),
ACS/ WFPC2: Elmegreen, Ford, Impey, Stapelfeldt
COS/ STIS: Hawley, Stocke, Vidal-Madjar
NICMOS/ WFC3: Davis, Dunlop, Kormendy, Sanders
(ii) Operational Issues:
Proposal Handling and Scheduling: Ford, Kormendy, Stapelfeldt
Software Analysis Tools: Davis, Impey, Sanders
Time Allocation Procedures: Hawley, Dunlop, Stocke
Solar System and Targets of Opportunity: Stapelfeldt, Vidal-Madjar
Archive: Davis, Dunlop, Impey
GO Funding: Elmegreen, Stocke
Users who have relevant input of general interest about any of these
issues, should contact the relevant STUC portfolio-holder or communicate
directly with George Miley. Information about the portfolios should be
clearly displayed in the STUC section of the STScI web site.
2. STATUS OF PROJECT AND SM3B SERVICING MISSION
The telescope appears to be performing well and preparation for the SM3b
service mission is proceeding on schedule. We congratulate the Project
for making considerable progress in alleviating the budget shortfall
mentioned in our previous report.
Although the first scientific priority of SM3b is to install the
Advanced Camera for Surveys, an additional activity that should have high
scientific priority is the installation of the NCS radiator on NICMOS. The
fundamental importance of an IR imaging capability on HST is underscored by the
number of recent major results that are due to observations with NICMOS. We
note the investigations of the low-mass populations of star clusters, the
discoveries of new brown dwarfs, EROs and distant galaxies, and
comparative studies of the IR and optical morphologies of faint galaxies. A major
recent highlight that received considerable publicity was the discovery
of the high-redshift supernova SN1997ff in the HDF-N and the constraints
imposed by the properties of this object and other NICMOS supernova
observations on the evolution of the Universe. Complementary
observations with NICMOS are essential in fully exploiting the power of the ACS in
some areas (e.g. studies of high-redshift supernovae). Although we realize
that installing the NCS will be a challenging part of SM3b, restoring NICMOS
to health is of great importance for astronomy.
From written material presented to STUC it appears that development of
both the WFC3 and COS are on schedule. No substantial problems have been
encountered in either case.
3. ADVANCED CAMERA FOR SURVEYS
The users are looking forward to the huge improvement in sensitivity and
resolution that will be provided by the ACS. We have no doubt that the
powerful combination of the HST and ACS will have a substantial impact
on fundamental science. Construction of the ACS appears to be on schedule.
Development of the ACS pipeline has also progressed considerably since
our last meeting. We are pleased that the geometrical distortion corrections
and the drizzle reduction routines are being incorporated into the
prototype system. Continued support should be provided to enable them to
be included into the definitive reduction pipeline.
A proposal by the ACS Science Team to upgrade the CCDs on the ACS Wide
Field Camera was discussed. The STUC formed a recommendation about this
question in the absence of one of its new members, Holland Ford, who
excused himself to avoid a possible conflict of interest as PI of the ACS.
STUC strongly endorses the proposal to replace the SITe CCDs of the WFC
with a Loral/Fairchild 4k x 4k CCD. All available evidence points to the
Fairchild device having better DQE and far superior cosmetic properties
than presently installed CCD. A particularly important reason for making
the change is that the Fairchild CCD has much better tolerance to
degradation in the space environment and should therefore have a useful
lifetime ~ 50% longer than that of the SITe device. The Fairchild CCD
would significantly increase the scientific return by enabling deeper
observations and faster surveys with data that are easier to calibrate
and characterize. We note that the risk analysis made by the project clearly
favors replacement of the CCD. The small additional risk in changing the
CCD would be incurred while the camera is on the ground, whereas the
worse reliability of the SITe CCDs would increase the risk of in-orbit
problems. Redundancy in the 4k x 4k CCD should result in less chance of readout
failures. Although we recognize that such a major change so close to
launch would be unusual, the benefits would be substantial. In the event that a
decision not to change the CCD is contemplated, the STUC would
appreciate further consultation on the matter through its Chairman or his representative.
We note that the problems with the SITe CCDs and the success of the new
Fairchild CCDs underlines the desirability of building redundancy early
into the development of detectors for space instruments.
4. SCIENTIFIC EFFECTIVENESS OF HST.
In our last report, the STUC encouraged the Institute to compile data
about scientific effectiveness of the HST that can be presented to scientists,
scientific administrators and government officials. We are therefore
pleased that the Science Division of the Institute has begun preparing
reports on the scientific highlights of HST and we complement them on an
excellent summary of the key achievements of the HST during 1999-2000.
We previously argued that these reports would be more effective if
complemented by quantitative and objective metrics of the scientific
productivity and impact of the HST. We are pleased that quantitative
data now exists to complement our subjective impressions about the success of
the HST. We learnt that an independent survey has shown that expressed
in terms of the cumulative number of discoveries between 1973 and 2000, the
HST is more than twice as productive than any other NASA facility.
The STUC also heard about the progress made by the Institute on using
science metrics to evaluate HST productivity and impact. In the past
the STScI Library has used its considerable expertise in this area to
compile a comprehensive list of HST-related publications and until recently these
were the only metric available for measuring the impact of HST research.
We applaud the work of the Library in leading this effort. As a result of
past STUC recommendations, a more extensive project to measure the
effectiveness is now underway led by the SPD and look forward to the presentation of
preliminary results of this work at the next STUC meeting.
We suggest that such an analysis be expanded further. Particularly
interesting would be a ranked list of the most cited papers and its use
to investigate which HST programs and instruments have produced the most
fundamental science advances. In carrying out such an investigation, we
would advocate taking into account (i) citation statistics as a more
robust measure of impact than counts of papers produced (ii) the substantially
larger completeness level of the printed volumes of the Science Citation
Index and the electronic "Web of Science" server compared with the
electronic ISI server.
5. SCIENCE OPERATIONS: GOALS AND BENCHMARKS
The STUC complements the Hubble division for initiating and leading a
study of the various steps in the HST process from proposal preparation to production of
papers. The study aims to develop goals and benchmarks for assessing each of the
various steps. We agree that such a detailed examination of the HST
process can be used to optimize resources in enhancing the scientific
effectiveness of the telescope. For example, if ways can be found to (i)
shorten the period between scheduling and observation, or (ii) shorten
the time between a proposal and distribution of the associated observed data
to the proposer to allow input to a proposal for the next TAC cycle,
substantial improvements to the scientific effectiveness of the HST
would result and qualitatively new science would be enabled.
We would appreciate updates at future STUC meetings on the progress and
implementation of the plan and input on setting priorities, when the
situation arises.
In addition, the Institute has instigated a group to Study possible
Archive and Reprocessing Enhancements (SHARE) and we also look forward to
hearing about its progress in the future.
6. SOFTWARE.
6.1 The Astronomers Proposal Tool. The STUC continues its strong support
for the development of the Astronomer's Proposal Tools (APT). As noted
in our last report, APT will offer powerful new capabilities for users in
developing their proposals. STUC applauds this STScI initiative, and is
impressed by the flexible management structure that allows such
innovation from modest staff resources. Initial feedback from users has been very
positive and constructive. The upcoming release of new versions of the
ACS exposure time calculator and the Archival Research tool will be of great
assistance in preparing Cycle 11 proposals. The STUC has two
suggestions for future work. First, to support the resumption of HST near-infrared
observations with NICMOS and WFC3, the STUC recommends that images from
the 2MASS survey be incorporated into APT visualizations on an equal footing
with images from the optical Digital Sky Survey. Secondly, consideration
should be given to developing a high-level "brainstorming" tool that
would allow potential proposers to explore the feasibility of HST observations
without having detailed knowledge of instrument capabilities. This
feature might expand the pool of HST users and encourage more
proposals. Eventually, APT might be mature enough that a combination of
the Phase 1 and Phase 2 processes could be considered to help decrease
the time from proposal submission to receipt of data. APT is an excellent
example of innovation within the Institute that tangibly benefits the
user community.
6.2 Grants Management System. The US users are enthusiastic about the
new GMS software for managing their HST grants and which replaces the old
GATOR system. A considerable amount of feedback was received. Grants are much
easier to administer using the new system.
6.3 Multi-Platform Support. Given the escalating use of LINUX within the
astronomical community and the stable but large group of Macintosh
users, STUC strongly recommends that multi-platform capabilities be
incorporated within the development of STSCI software systems such as GMS and APT. We
note that other major national astronomical facilities (NOAO, NRAO,
SIRTF) have already implemented key user software on the Linux platform.
7. TIME ALLOCATION PROCEDURES
We are pleased by the efficient operation of the Cycle 10 TAC process
and gratified that some of the STUC's previous recommendations were
successfully implemented in the Cycle 10 TAC procedure. The new proposal
categories have enabled several new classes of proposals in the areas of
calibration, innovation and joint Chandra-HST observations, but
surprisingly no proposal in the joint HST-NOAO observation category was
accepted. The new panel composition begun in Cycle 9 continued to be
effective in Cycle 10 in minimizing conflicts of interest. The fact that
the acceptance fractions were similar for panelists and non-panelists
and that the accepted proposals were equitably distributed amongst
disciplines was further evidence of the fairness of the process. The method of
triage, with the possibility for further discussion of a triaged proposal
continues to be an efficient process. We were especially encouraged that the
progressive orbit "subsidy" and the TAC Chairs' preliminary evaluation
of large proposals appears to have resulted in a proposal acceptance
fraction that is roughly independent of proposal size. It is also pleasing to
note that observing time requested by proposers was usually allocated in
full, i.e. without significant "trimming" of orbits.
Several changes are envisaged in the draft CP for Cycle 11 and the STUC
considered these at length. STUC supports the plan to continue and
expand the scope of large projects through the new Treasury Programs,
recommended by the HST Second Decade Committee. These programs are designed to
obtain coherent data sets that will enable the investigation of multiple
scientific questions and will have short or no proprietary periods for
data rights. We are pleased that the STScI has followed the recommendation of
STUC that Treasury Programs should be selected through the normal TAC
process. The Treasury Program will produce stronger links between HST
observations and those of other observatories, and will encourage the
development and distribution of high-level data products and analysis
tools for use by the broad astronomical community. The STScI should continue
to catalyze the definition of Treasury Program proposals by bringing
together astronomers from different disciplines such as was done by the recent
successful ACS Survey workshop. There are areas other than deep surveys
that would benefit from Treasury programs and we hope that the selected
proposals will embrace a wide range of astronomical disciplines.
However, the STUC is concerned that Treasury Programs could require funding
levels that may stress the resources available to the GO/AR program.
STUC considered the proposal by the Institute to reduce or eliminate
feedback to proposers of TAC comments. The goal of this measure is to
increase the efficiency of the proposal selection process and reduce the
overall time between proposal submission and scheduling. The STUC was
divided on the wisdom of this action. Because the comments need not be
communicated to proposers until a few months before the subsequent
proposal deadline, provision of such feedback should not affect the speed at
which a proposal can be scheduled. Most members of STUC believe that comments
about the technical feasibility of proposals are generally useful. However,
the usefulness of other comments is less important because the TAC rotates
between cycles and has no memory of previous comments. However, some
members feel strongly that, particularly for low-grade proposals, GOs
deserve some feedback given the considerable effort inherent in
preparing proposals. STUC recommends that the plan of the Institute to reduce the
feedback of TAC comments be carried out only on an experimental basis
for Cycle 11. Information about relative ranking should be communicated to
all proposers. Feedback of the comments should still be provided for all
proposals for which the technical feasibility is questioned. It is
important to alert the community in the next CP of these changes and
that feedback of comments will be reduced. The STUC would appreciate being
informed about the community's reactions to the experiment and suggests
that, on the basis of such reactions, the procedure for providing
feedback in future cycles be reevaluated.
8. GO FUNDING
The STUC endorses the idea, expressed both by the STScI and the Second
Decade Survey Committee, that increased funding for theoretical work
directed towards interpreting or stimulating HST observational research
is desirable. There is concern that this effort not compromise support for
the telescope's primary observational mission, including archival research.
This is a particular worry in view of the uncertainty in the funding
that will be needed to reduce and analyze data from the new large-array
instruments and the additional funding that will inevitably be required
to exploit new categories of HST proposals such as the Treasury Programs.
We believe that interaction between observers and theorists is crucial
in producing the most important astronomical results and that anything that
encourages separation between observation and theory is undesirable. We
note that by stimulating the constitution of joint
theoretical-observational teams the present grant system encourages
interaction between theorists and observers.
Nevertheless, STUC recognizes that the present grants program does not
readily support HST-related research that is primarily theoretical
and/or that has not yet stimulated observational follow-up. We therefore agree
with changing the guidelines for the grants program to enable such
theoretical research to be funded. However, we do not endorse
instituting a formal theory grants subprogram that would be allocated a
predetermined level of funding. The funding to be awarded to theoretical programs
should be determined through the usual competitive review process.
9. OTHER MATTERS
The dates of the next STUC meeting will be 25 and 26 October 2001.
Possible items for consideration include (i) updates on WFC3 and COS, (ii)
progress with PYRAF and application software prioritization, (iii) metrics on the
productivity of HST.