FUSE Observer's Advisory Committee
Meeting Minutes No. 10
2 April 2004

In Attendance: Dupree, Froning, Harper, Holberg, Sembach, St-Louis

By phone: Starrfield, Prochaska

FUSE Team: Blair, Kaiser, Kruk, Moos, Sahnow

NASA: Sonneborn, Hayes

The Committee congratulates the FUSE Team on the Senior Review (SR) proposal and wishes to thank all those who participated in the writing, for the obvious hard work that went into its preparation. Special thanks is also due Mary Beth Kaiser, who worked hard to put it all together. It is hoped that these efforts pay off in a successful review.

FOAC Membership:

Jay Holberg assumed the chair from Graham Harper. The FOAC wishes to thank its retiring chair, Graham Harper, for his valued service, as well as retiring committee members, Karen Leighly and Harriet Dinerstein. We also welcome new member, Alain Lacavelier, who was unable to join us for this meeting.

Action Items:

  1. George Sonneborn will contact prospective new FOAC members, with the goal of having two new members in place by the fall meeting.

Operations and Status (Blair):

Bill Blair reported on Cycle 4 performance statistics, noting a 37.4% efficiency in terms of science observing time. A summary of presently unschedulable holdover targets from Cycle 2, 3 and 4 was also presented. This was followed by a report on several recent changes to the planning and observing strategy that may result in significant increases in the regions of the sky available for observations and in particular, in the amounts of usable observing time in restricted regions. A new map of sky visibility was presented that was a dramatic improvement over the present map. The impact of these operational changes may well result in considerable new freedom to schedule difficult targets. The full impact of these changes should become evident in the coming weeks, as more experience is gained. These improvements have so far been realized without any relaxation in the Ram Avoidance Zone, which the project has decided not to change for the immediate future.

Recommendations and Action Items:

The FOAC concurs with the project's plans to highlight the above favorable changes at the SR. FOAC expressed concern about the number of remaining holdover targets from Cycle 2 and 3 and the potential impact on future observing cycles. The FOAC also expressed the hope that those changes will enable reductions to the number of difficult to schedule Cycle 2 and 3 holdover observations, prior to the start of Cycle 6.

The Action Items:

  1. George Sonneborn has indicated that in the coming weeks he will notify PIs, with remaining Cycle 2 and 3 observations, of the general status of their programs and the project's intention to make a concerted effort to execute as many as possible of these observations during Cycle 5. The FOAC urged that these notifications be made prior to the SR and that a policy for handling holdover targets be defined by the next FOAC meeting.
  2. The FOAC has asked that a more detailed evaluation of the new operational procedures and visibility constraints, and their potential impact on targeting restrictions, be provided to the FOAC prior to June 1.

Bright Targets (Blair):

A report was presented on efforts to develop safe and reliable techniques to observe bright targets. After restricted sky coverage, this class of targets is the most significant reason for uncompleted Cycle 2 and 3 epoch programs. Four strategies were described and the efforts to evaluate each of these presented. It was clear that the pace of these evaluation efforts remains constrained by FUSE team resources.

Action Items:

  1. The project will provide the FOAC an updated report on bright target observations prior to June 1, so that Cycle 6 proposers can be made aware of FUSE capabilities in this area. The FOAC felt that if no substantial progress in this area was achieved, then no further observations of this type should be encouraged in Cycle 6
  2. If promising techniques are developed, the FOAC felt that interested and willing PIs, with suitable existing bright target programs, be encouraged to become involved in the evaluation of the data as soon as possible.
  3. Of the four bright target methods under consideration, the scattered light technique has potentially the largest impact on FUSE team resources. This method should be looked at critically during the next FOAC meeting and a decision reached on its continued development.

Detector Performance (Blair):

The FUSE Team presented results of recent studies of detector performance. The potential loss of sensitivity in the LWRS apertures, with continued usage patterns, was flagged as a concern and strategies to move some observation to the MDRS were outlined. George Sonneborn indicated that it was his plan to evaluate the impact of moving existing observations conducted in HISTOGRAM mode to the MDRS, unless PIs were able to make a strong case for the LWRS. Programs whose S/N requirements would suffer would be compensated with increased observing time.


The FOAC concurs in George's decision and recognizes the need to develop a policy for high-count rate/high S/N observations for inclusion in the Cycle 6 NRA, prior to June 30.

Cycles 5 and 6 and Senior Review (Sonneborn):

George Sonneborn summarized the nature and distributions of upcoming Cycle 5 observations and outlined general plans for Cycle 6. There was overall satisfaction with the Cycle 5 results and general approval of FUSE plans for automated responses to Gamma-Ray bursts, in light of the upcoming launch of SWIFT. George also outlined plans for the SR. A third member of the presenting team has yet to be selected. A wide-ranging discussion of possible questions from the SR panel followed. In his email contribution to the FOAC meeting, Alain Lecavelier mentioned the inconvience, cost, and delay involved in submitting 12 paper copies of FUSE proposals from overseas.

Action Items:

  1. The FUSE Team will look into planetary observing possibilities in Cycle 6, in light of the less restrictive sky coverage.
  2. In response to Alain's comments, George Sonneborn will look into the possibility of electronic signatures on the Cycle 6 proposal form.

MAST (Sonneborn):

George Sonneborn reported on the improvement in MAST archiving and retrieval of FUSE data. The FOAC favorably noted statistics on MAST quick-look spectra. He also discussed plans for the reprocessing of prior FUSE data. The pace of this latter item may hinge on additional support contained in the SR budget. The FOAC and FUSE Team both expressed the need for a disclaimer to the downloadable ascii data which accompany the MAST quick look plots.

Action Items:

  1. The FUSE Team will write a draft disclaimer and circulate it to the FOAC.

CalFUSE (Sahnow):

The status of CalFUSE v3.0 was reviewed and a schedule for community release in May 2004 was presented. Of particular note was the development a detailed algorithm developed by Jean Dupuis and Derck Massa, which evaluates time- and wavelength-dependent photometric corrections based on multiple white dwarf observations.

Future FOAC Activity and FUSE Conference:

George Sonneborn reported the ongoing plans for the FUSE Conference in Victoria. It was noted that planning for the Cycle 6 NRA will need to be completed by June 30 and that FOAC advice is desired prior to that date. In addition, FOAC members who will be in attendance at the Victoria FUSE Conference, should try and plan a brief meeting, perhaps on Monday prior to the reception, to consider the results of the SR and to review plans for the fall FOAC meeting

Action Items:

  1. The FOAC will, after reviewing changes in sky coverage and bright target techniques, adopt a policy on holdover observations, prior to June 30.
  2. The FOAC will also need to be prepared to respond to those other issues mentioned in these minutes that are required for the NRA prior to June 30.
  3. George Sonneborn will make changes to the Conference website, more clearly indicating that the scientific sessions will began on the second day (Tuesday).

April 30, 2004

Jay Holberg, FOAC Chair

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