LIGO-G M LIGO I Science Run Barry Barish PAC Meeting - LHO December 13, 2000
LIGO-G M 2 The LIGO I Science Run Data & Computing Group Operations Plan 9 th Meeting of the LIGO PAC LIGO Livingston Observatory Livingston, Louisiana 13 December 2000 Albert Lazzarini LIGO Laboratory Caltech
LIGO-G M 3 LIGO Plans schedule 1996Construction Underway (mostly civil) 1997Facility Construction (vacuum system) 1998Interferometer Construction (complete facilities) 1999Construction Complete (interferometers in vacuum) 2000Detector Installation (commissioning subsystems) 2001 Commission Interferometers (first coincidences) 2002Sensitivity studies (initiate LIGO I Science Run) LIGO I data run (one year integrated data at h ~ ) 2005+Begin ‘advanced’ LIGO installation
LIGO-G M 4 Revised Schedule As proposed to the NSF – May 2000
LIGO-G M 5 Significant Events
LIGO-G M 6 operating as a Michelson with Fabry-Perot arms reduced input laser power (about 100 mW) without recycling noise level is a factor of above the final specification sources of excess noise are under investigation Strain Sensitivity Nov km Hanford Interferometer
LIGO-G M 7 LIGO I steps to science run commissioning interferometer »robust locking »three interferometers »sensitivity »duty cycle interleave engineering runs »implement and test acquisition and analysis tools »characterization and diagnostics studies »reduced data sets »merging data streams »upper limits
LIGO-G M 8 LIGO/LSC Data Analysis Model Now: »Initial engineering runs starting to set the stage for how science, research is done »Data being archived at Caltech in HPSS »Access from archive according to LIGO Laboratory MOUs »“Stress testing” of software and hardware systems - both LDAS and GDS/DAQS/CDS »Initial data analyses focus on –sorting out commissioning issues, –understanding environment, –Calibrations, data conditioning, pre-processing
LIGO-G M 9 LIGO/LSC Data Analysis Model Near-term (2Q2001): »LIGO science will focus on using engineering runs to extract meaningful first upper limits »Organized around 4 upper limits papers using ~1 week of data in 2Q2001 »Opportunity to set current best upper limits on these classes of sources »Provides a basis to "exercise" the LSC data analysis groups »Provides a basis for future organization of the LIGO I Science Run search teams –groups will expand as interest grows in LIGO science. Problems: »LDAS readiness to support the engineering run goal »Strategy is to limit scope primarily to LDAS supported goals
LIGO-G M 10 Astrophysical Signatures data analysis Compact binary inspiral: “chirps” »NS-NS waveforms are well described »BH-BH need better waveforms »search technique: matched templates Supernovae / GRBs: “bursts” »burst search algorithms – eg. excess power; time-frequency patterns »burst signals in coincidence with signals in electromagnetic radiation »prompt alarm (~ one hour) with neutrino detectors Pulsars in our galaxy: “periodic” »search for observed neutron stars (frequency, doppler shift) »all sky search (computing challenge) »r-modes Cosmological Signals“stochastic background”
LIGO-G M 11 LIGO/LSC Data Analysis Model LIGO I Science Run (2Q2002): »Key astrophysical searches follow the LSC Data Analysis White Paper plan: »Organized around teams, as in near-term upper limit studies –Open to all who are willing to work »LIGO Lab LDAS resources to be used for searches will be shared among the teams »LSC member institutional resources used by individual researchers »Longer term: establish 5 LIGO/LSC Tier 2 centers (“University Research Centers” or URCs) to provide additional computational, data distribution resources across collaboration
LIGO-G M 12 Inspiral Sources LSC Upper Limit Group Inspiral Sources Co-chair Patrick Brady, Gabriela Gonzalez Bruce Sukanta Douglas Patrick Duncan Jordan Nelson Jolien S.V. Gabriela Andri Gregg Syd Tom David B.S. Peter
LIGO-G M 13 Interferometers astrophysical sources Compact binary mergers Sensitivity to coalescing binaries Binary inspiral ‘chirp’ signal future
LIGO-G M 14 Interferometer Data 40 m Real interferometer data is UGLY!!! (Gliches - known and unknown) LOCKING RINGING NORMAL ROCKING
LIGO-G M 15 The Problem How much does real data degrade complicate the data analysis and degrade the sensitivity ?? Test with real data by setting an upper limit on galactic neutron star inspiral rate using 40 m data
LIGO-G M 16 “Clean up” data stream Effect of removing sinusoidal artifacts using multi-taper methods Non stationary noise Non gaussian tails
LIGO-G M 17 Inspiral ‘Chirp’ Signal Template Waveforms “matched filtering” 687 filters 44.8 hrs of data 39.9 hrs arms locked 25.0 hrs good data sensitivity to our galaxy h ~ mHz -1/2 expected rate ~10 -6 /yr
LIGO-G M 18 Detection Efficiency Simulated inspiral events provide end to end test of analysis and simulation code for reconstruction efficiency Errors in distance measurements from presence of noise are consistent with SNR fluctuations
LIGO-G M 19 Setting a limit Upper limit on event rate can be determined from SNR of ‘loudest’ event Limit on rate: R < 0.5/hour with 90% CL = 0.33 = detection efficiency An ideal detector would set a limit: R < 0.16/hour
LIGO-G M 20 Two Sites - Three Interferometers »Single Interferometernon-gaussian level ~50/hr »Hanford (Doubles) correlated rate (x1000) ~1/day »Hanford + Livingston uncorrelated (x5000) <0.1/yr Coincidences between LLO & LHO
LIGO-G M 21 Burst Souces LSC Upper Limit Group Burst Sources Co-chair Sam Finn, Peter Saulson Warren Barry Biplab Jim Eric Kent Ed Ronald Sam Ray Ken Joe Gabriela Andri Bill Warren Masahiro Ito S. Al Szabi Genakh Soumya Benoit Soma Fred Ravha Rahkola Peter
LIGO-G M 22 pulsar proper motions Velocities - young SNR(pulsars?) > 500 km/sec Supernovae asymmetric collapse?
LIGO-G M 23 LIGO I science run Strategy »initiate science run when good coincidence data can be reliably taken and straightforward sensitivity improvements have been implemented (~ 7/02) »Then, interleave periods of science running with periods of sensitivity improvements Goals »obtain 1 year of integrated data at h ~ »searches in coincidence with astronomical observations (eg. supernovae, gamma ray bursts) »searches for known sources (eg. neutron stars) »stand alone searches for compact binary coalescence, periodic sources, burst sources, stochastic background and unknown sources at h ~ sensitivities Exploit science at h ~ before initiating ‘advanced’ LIGO upgrades
LIGO-G M 24 LIGO/LSC Data Analysis Model Throughout Engineering & Science Runs, the Laboratory’s Data & Computing Group fulfills the following roles: »LIGO science, data analysis: scientific staff are actively engaged in the astrophysics searches »Simulation & Modeling: detector support, data analysis »Continuous management and movement of large volumes of data »Maintaining pipeline analyses running, archive running »Software maintenance/improvements/enhancements »LSC support, visitors »LIGO Laboratory-wide IT support
LIGO-G M 25 Data & Computing Group Principal LDAS activities during operations
LIGO-G M 26 Data & Computing Group Principal Modeling & Simulation activities during operations
LIGO-G M 27 Data & Computing Group Principal General Computing activities during operations
LIGO-G M 28 LDAS Operations Statistics derived from actual experience
LIGO-G M 29 * MIT, LHO, and LLO have local General Computing staff * LHO, and LLO have local LDAS staff
LIGO-G M 30 Data and Computing Budget Breakdown
LIGO-G M 31 LDAS Operations Budget Hardware Support
LIGO-G M 32 Requested Increment - Operations
LIGO-G M 33 Conclusions science run Short term -- »implement LDAS –4 sites; computing; archiving »engineering runs –data handling and access, reduced data sets –diagnostics; characterize instrument and data –algorithms; statistics Longer Term »LIGO Lab support for Science Run Support Required »LDAS procurement and implementation »incremental resources requested –manpower –maintenance and networking –support of LSC