WORKSHOP TO CREATE SOURCE WORKING GROUPS
FOR INTERFEROMETRIC GRAVITATIONAL WAVE DETECTORS

Louisiana State University and LIGO Livingston Observatory
March 20-23, 2001
Second circular

For information on registration, NSF travel support, and further details please check the meeting webpage:

http://relativity.phys.lsu.edu/conf.html

Scientific Organizing Committee: Patrick Brady, Sam Finn, Tom Prince, Jorge Pullin, Bernard Schutz, Kip Thorne, and Rai Weiss.

MOTIVATION FOR THE WORKSHOP

This Workshop is motivated by the growing need for a tighter coupling of the gravitational-wave source-analysis community (including numerical relativists) to the experimental gravitational-wave projects. Examples of major needs, this year and next, are: (1) Information from the source-analysis community on the phase evolution of waves from the late ("IBBH") stage of compact binary inspiral (the stage where post-Newtonian expansions are failing), for use in LIGO-I matched-filter searches for these waves. (2) partial information from numerical relativity simulations of black-hole merger waveforms --- information to be used as an aid in applying the excess-power algorithm in LIGO-I searches for merger waves. (3) Waveforms, computed via black-hole perturbation theory, for small-mass bodies in generic orbits around massive Kerr black holes; these are needed this year, as input for firming up LISA's design noise curve by December 2003. In each of these examples, and in many others that mostly have longer timescales, the source analysis needs to be guided by the data-analysis needs, and the development and scoping out of data analysis algorithms is like to be more effective if source analysts participate to some degree.

SIDE REMARK: A POSSIBLE NASA/NSF COMPUTATIONAL INITIATIVE

In parallel with this Workshop, NASA and NSF are considering the possibility of creating a new, joint NASA/NSF computational initiative on gravitational-wave science (and perhaps other things). Beverly Berger [NSF] and Michael Salamon [NASA] will likely appoint a task group to provide advice on this initiative, and the task group may seek input from the gravitational-wave community at this Workshop, and by other mechanisms.

GOALS OF THE WORKSHOP

The Goals of the Workshop [as developed by the scientific organizing committee] are:

a. To take stock of the current status of source analyses relative to the goal of producing waveforms for LIGO and LISA on the timescales that those waveforms are needed.

b. To initiate the development of structures which allow source analysis scientists to communicate efficiently with data analysis scientists and with each other. These structures are intended to make the work of source analysts more effective for LIGO and LISA. One proposed structure is the Source Groups described in the first circular and in the name of the Workshop.

STRUCTURE AND SCHEDULE FOR THE WORKSHOP

The Workshop Organizing Committee has developed the following tentative structure/schedule for the Workshop. It is likely that all meetings will be held at the LIGO Livingston Site; if not, they will be held somewhere else in the vicinity of LSU and Baton Rouge.

a. Wednesday March 20, beginning at 4PM or later [which permits flying into Baton Rouge that day from almost anywhere in the US], and possibly continuing into the evening with supper catered: Plenary Session of Workshop. Source analysts meet, and data analysts join them after their closed LIGO-I meeting. Purpose is to take stock of (i) where source simulations now stand relative to LIGO's and LISA's waveform needs and (ii) what obstacles must be surmounted to meet those needs. This will provide input for three talks in the LSC plenary session the next day.

b. Thursday, ~8AM to ~3 or 4pm: LSC Plenary session. Source analysts get exposed to the LSC and to the current status of LIGO. Source analysts give three talks, of duration no longer than 15 minutes each, on the current status of source simulations relative to LIGO's waveform needs, and on obstacles to achieving those needs, in three areas. Those areas have tentatively been chosen to be: i. binary black holes --- both merger and late inspiral ii. neutron-star tidal disruption iii. stellar core collapse These talks will be followed by 15 minutes of discussion.

c. Thursday, ~4pm onward, probably continuing into Friday morning. Possible talks and discussions, in no special order, are:

i. Presentation on the LISA science requirements and report on activities of LISA Working Group 1. Discussion.

ii. Data analysts give talks about how the source analysts can contribute to LIGO and LISA, especially in the near future; see the examples at the beginning of this circular. Discussion.

iii. Presentation on the Workshop Goal of initiating development of structures for source-analysis scientists to communicate with data-analysis scientists, and with each other. Discussion of this goal and of possible structures including source groups

iv. Discussion of how the source-analysis community should be connected, formally, if at all, to the LSC ( http://www.ligo.caltech.edu/LIGO_web/lsc/lsc.html) and/or ASIS ( http://www.lsc-group.phys.uwm.edu/lscasis/) and to LISA Working Group 1 ( http://www.tapir.caltech.edu/listwg1/)

v. Presentation on a possible NASA/NSF computational initiative in gravitational wave science, and on the issues that the Berger/Salamon task group for this initiative is charged to write about. Discussion.

d. Friday: Continue the Workshop Plenary Session if necessary; then break up into parallel sessions. Because of space constraints there can be no more than about 3 parallel sessions of the Workshop going at once. There might be parallel sessions based on source types --- binary black hole, sources involving neutron stars (fluids), and inspiral of small-mass bodies into massive black holes. There might be a session on the issues being discussed by the Berger/Salamon task group. There might be a session focusing on formal structures for interfacing source analysis to LSC/ASIS. ... There also will be sessions in which ASIS members take care of other ASIS business

e. Saturday: Perhaps parallel sessions continue for awhile, followed by:

Workshop Plenary Session to develop a proposal for posssible structures such as source groups and how they might be connected to LSC/ASIS, followed by:

LSC Plenary Session at which the Workshop reports on its conclusions and they are discussed, but no final decisions are made. LSC Plenary Session at which the Workshop reports on its conclusions.