LCGT data analysis white paper --DRAFT
Contents
Introduction
Searches for signals from compact binary coalescence
- == Gravitational waves from the coalescence of compact binary systems . . . . . . . . . . . . . 5 == Sciencegoals .......................................... 6
== SearchStrategies ........................................ 7
- === Matched filtering .................................... 8 === Analysis pipeline .................................... 8 === Background estimation ................................. 9 === Instrumental and environmental vetoes ........................ 10 === Efficiency evaluation .................................. 10 === Follow-up of candidate events ............................. 10 === Pipeline of pipelines .................................. 11 === Uncertainties in theoretical waveforms. . . . . . . . . . . . . . . . . . . . . . . . . 11 === Astrophysical rates ................................... 12 === Externally triggered searches.............................. 12 === Current status and goals..................................... 13 === Recently completed searches.............................. 13 === Near-term priorities................................... 13 === Pipeline development.................................. 14
2.4.4 S5/VSR1 goals ..................................... 15
2.4.5 S6/VSR2 goals ..................................... 18
2.4.6 Advanceddetectorera ................................. 22
3 Searches for general burst signals 23 3.1 SourcesofGravitationalWaveBursts ............................. 23
3.2 ScienceGoalsoftheBurstGroup ............................... 25
3.3 Recentscienceresults...................................... 27
3.4 Searchpipelineoverview .................................... 28
3.4.1 Detectionalgorithms .................................. 28
3.4.2 Sourcelocationandwaveformreconstruction . . . . . . . . . . . . . . . . . . . . . 30 3.4.3 Dataqualityandvetoes................................. 30
3.4.4 Simulations....................................... 30
3.4.5 Background....................................... 31
3.4.6 Detectioncriteria .................................... 32
3.5 Statusandprospectsofburstsearches ............................. 32
3.5.1 Triggeredsearches ................................... 32
3.5.2 Untriggeredsearches .................................. 36
3.6 Plansandprospectsfor2008-2009 ............................... 37
3.6.1 completionofS5/VSR1analysis ........................... 37
3.6.2 preparationofS6/VSR2(mid2009) .......................... 38
3.6.3 Developmentprojects ................................. 39
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LSC-Virgo data analysis white paper -DRAFT as of 2008/10/28
4 Searches for continuous-wave signals 40 4.1 Non-accretingpulsars...................................... 41
4.1.1 TimedomainBayesianmethod ............................ 41
4.1.2 WideParameterSearchoftheCrabPulsar) . . . . . . . . . . . . . . . . . . . . . . 43 4.1.3 Virgotargetedsearches ................................ 43
4.2 Non-pulsingnon-accretingneutronstars ............................ 44
4.2.1 CassiopeiaA ...................................... 45
4.2.2 Virgosemi-targetedsearch ............................... 45
4.2.3 Othertargets ...................................... 46
4.3 Previouslyunknownnon-accretingobjects ........................... 46
4.3.1 Semicoherentsearches ................................. 47
4.3.2 Cross-correlationsearches ............................... 48
4.3.3 Hierarchical Searches and Einstein@Home .................... 49
4.3.4 Searchesforsourcesinglobularclusters . . . . . . . . . . . . . . . . . . . . . . . 50 4.3.5 Searchesforsourcesnearthegalacticcenter . . . . . . . . . . . . . . . . . . . . . 51 4.3.6 Semi-targeted searches for “transient CW signals” . . . . . . . . . . . . . . . . . . 51 4.3.7 Virgoblindsearches .................................. 52
4.4 Accretingneutronstars ..................................... 53
4.4.1 Cross-correlation searches for known binary systems . . . . . . . . . . . . . . . . . 53 4.4.2 Sidebandsearchforknownbinarysystems . . . . . . . . . . . . . . . . . . . . . . 54 4.4.3 TwoSpectsearchforunknownbinarysystems . . . . . . . . . . . . . . . . . . . . 55 4.4.4 Quadraticsearchforunknownbinarysystems . . . . . . . . . . . . . . . . . . . . 55 4.5 NeedsandplansforS6/VSR2 ................................. 56
5 Searches for stochastic backgrounds 57 5.1 Sources of Stochastic Gravitational-wave Background . . . . . . . . . . . . . . . . . . . . . 57 5.2 StochasticSearchMethod.................................... 57
5.2.1 All-SkySearch ..................................... 58
5.2.2 DirectionalSearch ................................... 59
5.2.3 Mapping ........................................ 59
5.2.4 Multi-baseline:LSC/VIRGOjointsearch . . . . . . . . . . . . . . . . . . . . . . . 60 5.2.5 H1H2All-SkySearch ................................. 61
5.3 ResultsandPlans ........................................ 61
5.3.1 S4Results ....................................... 61
5.3.2 StatusofS5Searches.................................. 62
5.3.3 PlansforS6Searches.................................. 63
6 The characterization of the data 64 6.1 LIGODetectorCharacterization ................................ 64
6.1.1 Introduction....................................... 64
6.1.2 StorageofDataQualityInformation ......................... 65
6.1.3 SoftwareInfrastructure ................................. 66
6.1.4 Calibrations....................................... 68
6.1.5 Timing ......................................... 69
6.1.6 GlitchInvestigations .................................. 70
6.1.7 EnvironmentalDisturbances .............................. 71
6.1.8 DataRunSupport.................................... 72
6.1.9 LSCPresenceattheObservatories........................... 73
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LSC-Virgo data analysis white paper -DRAFT as of 2008/10/28
6.2 GEODetectorCharacterization................................. 73
6.2.1 Introduction....................................... 73
6.2.2 DataAcquisitionandtiming .............................. 74
6.2.3 Straincalibration .................................... 74
6.2.4 Glitchstudies ...................................... 75
6.2.5 Dataquality....................................... 76
6.2.6 GEOdetectoranddatacharacterisationpost-S5 . . . . . . . . . . . . . . . . . . . . 77 6.3 VirgoDetectorCharacterization ................................ 78
6.3.1 Introduction....................................... 78
6.3.2 Detectorstatusmonitors ................................ 78
6.3.3 CalibrationandHardwareInjections .......................... 79
6.3.4 Noisestudies ...................................... 79
6.3.5 DC resulting from the searches for impulsive events . . . . . . . . . . . . . . . . . 80 7 Computing and Software 81 7.1 Currentstatus .......................................... 81
7.2 ActivitiesinsupportofLDGOperations ............................ 82
7.3 DataAnalysisSoftwareDevelopmentActivities . . . . . . . . . . . . . . . . . . . . . . . . 83 7.4 Intermediate-termdevelopmentactivities............................ 85
7.5 Long-termgoals......................................... 87
7.6 Virgocomputingandsoftware ................................. 88
7.6.1 ComputingattheEGO/Virgosite ........................... 88
7.6.2 ComputingatCNAF(Bologna,Italy) ......................... 89
7.6.3 ComputingatCCIN2P3(Lyon,France) ........................ 89
7.6.4 Virgosoftware ..................................... 89
References 90 4