Minutes of HEASARC Users Committee Meeting

March 23, 2001

The Agenda for the meeting is given below as Appendix 1.

0. Introductions

Present at the meeting were HUG members J. Grindlay (chair), N. Brandt, D. Buote, D. Chakrabarty, M. Donahue, W. Heindl, K. Leighly, J. Osborne and P. Slane. Reshmi Mukherjee was not able to attend the meeting; David Buote and Karen Leighly were welcomed as new members.

Previous members (Chryssa Kouveliotou, Jonathan McDowell, Ron Remillard and Alyn Tenant) were thanked for their service.

Minutes from the previous meeting (2/25/00) were reviewed and accepted. The Committee was pleased that most of the recommendations had been implemented or at least considered.

In the manner introduced in the last Minutes, we provide very brief summaries of the presentations and discussion of each Agenda item, followed by any

    ---Questions asked by the Committee,
    ***Concerns, noted by the Committee, and
    >>>Recommendations, for consideration by the HEASARC and NASA

1. HEASARC Overview (Nick White)

The HEASARC did well in the recent (June, 2000) Senior Review, being among the top-rated data centers. Nevertheless, due to funding pressures its FY01 budget ($1.42M) had remained flat, supporting at least in part a staff of 7 scientists and 7 programmers. The Committee was
*** concerned that this constant funding, without inflation increases, did not permit new initiatives but only supported maintenance-level operations.

However, the AISR program was providing some new support (e.g. for development of Skyview/Virtual Sky).

The (few) weaknesses noted by the Senior Review (multi-wavelength database inter-connectivity not optimal; ARGUS interface could be improved) were being dealt with.

Several questions, some with implied suggestions, were asked by the Committee (or, in some cases, by their colleagues) from their general use of HEASARC tools or databases:

    ---how is the balance set between development of archiving and
       analysis tools; how are priorities set generally?
    ---could support for Linux users be provided?
    ---could presentations of data from different missions be made to
       have more similar formats so that it was easier to inter-compare
       mission data (e.g. Chandra vs. XMM; Chandra-HST joint observations)?
    ---could documentation for the group PHA function in XSPEC be improved
       so users had better sense of how to make optimum binning of low
       statistics data?
    ---can EPO activities be extended beyond K-12 to more completely
       serve college audience?
On the general EPO issue, the Committee remains impressed by the fine level of work and new initiatives being done at HEASARC. The fact that small EPO projects, on individual grants, could not be pooled for more effective combined efforts was of some concern to the Committee.

2. The Web walkthrough was deferred until later in the meeting due to network problems.

3. The HEASARC interface with the Chandra archive was only discusssed briefly since neither A. Rots or S. Murray were able to attend.

>>>The Committee would like to review this HEASARC-Chandra interface more completely at its next meeting.

4. XMM GOF (Steve Snowden)

Despite full operations, only datasets for 3 GO observations had been received as of the meeting time. Discussions were still ongoing as to the future plans for being able to ingest, or mirror, XMM data into a HEASARC archive. The Committee was pleased to hear that the GOF was developing a new version of the Quick Sim (simulator tool) in time for the upcoming AO2 (scheduled for Sept. 2001).

5. HETE-2 (Mike Corcorran)

HETE-2 data formats were still not defined (of concern to the committee) although first data products had just become available (Feb. 2) for the archive. Data product definitions, data verification procedures and editing, and analysis tools were all still to be defined with MIT.

6. Archive Usage/Status (Steve Drake)

The HEASARC archive usage continues to grow at an impressive rate (~2 Gb/day), with the largest influx still from RXTE. Total archive size (Jan. 2001) was 2200 Gb. The RAID storage capacity was planned to be increased to 3800Gb in April 2001, and projections for upcoming new missions (INTEGRAL: 1000Gb/year) will further increase the system. The INTEGRAL archive struture has been largely worked out. BROWSE usage increased significantly over the past year. The Committee was generally pleased with download speeds and access. The Committee remains
***concerned that access to BeppoSAX/WFC data archive is still not available.

7. Software Development: Demos and Feedback

BROWSE (Tom McGlynn):
Bilateral links to both STScI/MAST and to CXT (Chandra) archives are being developed and will allow access via HEASARC to these archives. New planned features such as access to the CDS VizieR tables and cross correlations with other results were mentioned. When these new tools are available, the Committee
    >>>recommends simple documentation, with examples, for how the user
       can quickly use these features
    >>>suggests that the HUG could  be a beta-test site for new tools
       as developed
    >>>suggests that a clickable dynamic history-map (where user has BROWSED)
       be added
The Committee recognizes the application of these new BROWSE capabilities for future NVO use.

SKYVIEW (Tom McGlynn):
This continues to improve, with impressive new features (e.g. mosaics). The Committee was interested that POSS-2 will be added soon?

SKYMORPH and ClassX (Tom McGlynn):
These new projects, supported by AISR grants, offer new capabilities: access to the Near Earth Asteroid data (SkyMorph), which can allow more general temporal variation analysis, and a generalized x-ray source classifier (ClassX). Both are ambitious, and the Committee looks forward to learning more (particularly about ClassX) as they are developed.

FTOOLS update (Bill Pence):
The Committee was interested to learn more about the new (v3.0) Fv release which allows direct interface to SkyView with interactive features not available from the Skyview website. The Committee noted that the flux (and centroid) extraction would be enhanced if there were provision to subtract local background(s) either from a surrounding concentric annulus or separate circular or square region on the image.

HERA (Bill Pence):
This new AISR grant-supported effort looks to be exciting, allowing web-based analysis tools to operate directly on archival data. This may be most useful for expanding the user community to non-expert astronomers (non-HEA) or to EPO users. However the Committee noted it may also be very effective for doing batch mode or script-driven analysis of large datasets for survey science.

XSPEC (Keith Arnaud):
The user community continues to be indebted to Keith for continuing the development of this widely used package. The new features (e.g. new absorption models; low-N statistics tools soon to be released) are anticipated. The spectral line fitting and identification package and general grating analysis should be compared with Ciao tools being similarly developed.

8. Additional general comments:

The Committee notes that it would be generally desirable to
    ---make OGIP standards and documentation easier to find
    ---enable users to more easily integrate Ciao tools and Ftools; and
       XMM tools?
    ---improve and simplify documentation; add more cookbook examples

8. New HUG members?

The Committee discussed possible new members to replace those who might be rotating off the HUG. These included Bob Rutledge, Rita Sambruna and Jimmy Irwin.

The meeting was adjourned at 4:45pm.

Appendix 1: Agenda for HUG Meeting, March 23, 2001

9.00 Introductions 9.15 HEASARC and Data Archives Overview (including future HEASARC milestones and a discussion about the impact of the NVO initiative)- Nick White 10.15 A Walk Through the HEASARC Web - Karen Smale and Steve Drake 10.45 Coffee break 11:00 HEASARC Interface with Chandra Archive - Arnold Rots or Steve Murray 11:15 XMM-Newton Archive and GOF - Steve Snowden 11:30 HETE-II Archive - Mike Corcoran 11:40 Archive Usage for Past & Present Missions, Browse Usage Statistics, Database Creation Activities and 2001-2 Projections - Steve Drake 12.00 Lunch 13.00 Software Activities at the HEASARC a) Browse: Current state and capabilities (inc. Chandra data access via HEASARC Browse) and future plans (e.g., Incorporation Of Vizier tables into Browse) - Tom McGlynn b) SkyView - Tom McGlynn c) Ftools update & HERA (new Web-based analysis capability) - Bill Pence & Christina Heikkila d) Xspec Update (inc. support for XMM-Newton & Integral) - Keith Arnaud 14:00 Breakout session for demos, e.g., on new BROWSE interfaces, and small group discussions on issues that have been raised 15.00 Coffee Break 15.15 Executive session of HUG 16.00 Feedback to HEASARC from HUG 16.30 New members proposed to replace exiting HUG members