J/ApJ/804/114 Parameter-estimation performance with LIGO (Berry+, 2015)
Parameter estimation for binary neutron-star coalescences with realistic noise
during the advanced LIGO era.
Berry C.P.L., Mandel I., Middleton H., Singer L.P., Urban A.L., Vecchio A.,
Vitale S., Cannon K., Farr B., Farr W.M., Graff P.B., Hanna C.,
Haster C.-J., Mohapatra S., Pankow C., Price L.R., Sidery T., Veitch J.
<Astrophys. J., 804, 114 (2015)>
=2015ApJ...804..114B 2015ApJ...804..114B
ADC_Keywords: Interferometry
Keywords: gravitational waves; methods: data analysis; stars: neutron; surveys
Abstract:
Advanced ground-based gravitational-wave (GW) detectors begin
operation imminently. Their intended goal is not only to make the
first direct detection of GWs, but also to make inferences about the
source systems. Binary neutron-star mergers are among the most
promising sources. We investigate the performance of the
parameter-estimation (PE) pipeline that will be used during the first
observing run of the Advanced Laser Interferometer Gravitational-wave
Observatory (aLIGO) in 2015: we concentrate on the ability to
reconstruct the source location on the sky, but also consider the
ability to measure masses and the distance. Accurate, rapid sky
localization is necessary to alert electromagnetic (EM) observatories
so that they can perform follow-up searches for counterpart transient
events. We consider PE accuracy in the presence of non-stationary,
non-Gaussian noise. We find that the character of the noise makes
negligible difference to the PE performance at a given signal-to-noise
ratio. The source luminosity distance can only be poorly constrained,
since the median 90% (50%) credible interval scaled with respect to
the true distance is 0.85 (0.38). However, the chirp mass is well
measured. Our chirp-mass estimates are subject to systematic error
because we used gravitational-waveform templates without component
spin to carry out inference on signals with moderate spins, but the
total error is typically less than 10-3M☉. The median 90%
(50%) credible region for sky localization is ∼600deg2 (∼150deg2),
with 3% (30%) of detected events localized within 100deg2. Early
aLIGO, with only two detectors, will have a sky-localization accuracy
for binary neutron stars of hundreds of square degrees; this makes EM
follow-up challenging, but not impossible.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablec1.dat 97 333 Simulated binary neutron-star (BNS) signals of
detected events for 2015 scenario using
recolored noise
tablec2.dat 96 333 Detections and sky-localization areas for 2015
scenario using recolored noise
tablec3.dat 71 333 Parameter-estimation accuracies for 2015 scenario
using recolored noise
tablec4.dat 71 250 Parameter-estimation accuracies for 2015 scenario
using Gaussian noise
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See also:
J/ApJ/760/12 : LIGO/Virgo gravitational-wave (GW) bursts (Abadie+, 212)
J/ApJ/713/671 : Gravitational waves from pulsars (Abbott+, 2010)
Byte-by-byte Description of file: tablec1.dat
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Bytes Format Units Label Explanations
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1- 5 I5 --- EvID [4532/14218] Event detection ID
(coinc-event-id) (G1)
7- 11 I5 --- SimID [138/48517] Simulation ID (simulation-id) (G2)
13- 23 F11.5 d MJD MJD of simulated signal (1)
25- 29 F5.1 deg RAdeg Right ascension; decimal degrees (J2000)
31- 35 F5.1 deg DEdeg Declination; decimal degrees (J2000)
37- 39 I3 deg Inc [4/178] Binary orbital inclination angle
41- 43 I3 deg PolA [0/360] Polarization angle (2)
45- 47 I3 deg Phase [0/360] Orbital phase at coalescence (coa-phase)
49- 51 I3 Mpc Dist [2/121] Distance
53- 56 F4.2 Msun M1 [1.2/1.6] Mass of binary component 1
58- 61 F4.2 Msun M2 [1.2/1.6] Mass of binary component 2
63- 67 F5.2 --- spin1x [-0.05/0.05] Spin of binary component 1, x-axis
69- 73 F5.2 --- spin1y [-0.05/0.05] Spin of binary component 1, y-axis
75- 79 F5.2 --- spin1z [-0.05/0.05] Spin of binary component 1, z-axis
81- 85 F5.2 --- spin2x [-0.05/0.05] Spin of binary component 2, x-axis
87- 91 F5.2 --- spin2y [-0.05/0.05] Spin of binary component 2, y-axis
93- 97 F5.2 --- spin2z [-0.05/0.05] Spin of binary component 2, z-axis
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Note (1): Time of arrival at geocenter of gravitational waves from last stable
orbit.
Note (2): According to convention in Appendix B of Anderson et al.
(2001PhRvD..63d2003A 2001PhRvD..63d2003A).
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Byte-by-byte Description of file: tablec2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 5 I5 --- EvID [4532/14218] Detection ID (coinc-event-id) (G1)
7- 11 I5 --- SimID [138/48517] Simulation ID (simulation-id) (G2)
13- 14 A2 --- Det [HL] Detector network (network) (1)
16- 19 F4.1 --- SNR [10/100] Network SNR (snr-net) (2)
21- 24 F4.1 --- SNR.H [5/62] SNR in Handford detector (snr-H) (2)
26- 29 F4.1 --- SNR.L [5/79] SNR in Livingston detector (snr-L) (2)
31- 34 F4.2 Msun M1r [1.2/2.1] Recovered mass 1
36- 39 F4.2 Msun M2r [0.9/1.6] Recovered mass 2
41- 47 F7.2 deg2 Ara.5 The 50% area, BAYESTAR (rapid-area50) (3)
49- 55 F7.2 deg2 Ara.9 The 90% area, BAYESTAR (rapid-area90) (3)
57- 63 F7.2 deg2 Ara [0.06/2727] Searched area, BAYESTAR
(rapid-searched) (3)
65- 71 F7.2 deg2 Ape.5 The 50% area, LALINFERENCE (pe-area50) (4)
73- 79 F7.2 deg2 Ape.9 The 90% area, LALINFERENCE (pe-area90) (4)
81- 87 F7.2 deg2 Ape [0.07/9810] Searched area, LALINFERENCE
(pe-searched) (4)
89- 96 E8.2 s-1 FAR [2e-14/4e-10] False alarm rate
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Note (1): All detections are for a two-detector Hanford-Livingston (HL) network.
Note (2): Blank if SNR<4 or detector is not online. The network SNR is
calculated by adding individual detectors in quadrature so
SNR2=SNR.H2+SNR.L2.
Note (3): The BAYESTAR code (Singer 2015PhDT.........6S 2015PhDT.........6S;
Singer et al. 2014ApJ...795..105S 2014ApJ...795..105S), infers sky location from dat
a returned from the detection pipeline. See section 1.
Note (4): Calculating estimates for parameters beyond sky location is done using
the stochastic-sampling algorithms of LALInference
(Veitch et al. 2015PhRvD..91d2003V 2015PhRvD..91d2003V). See section 1.
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Byte-by-byte Description of file: tablec[34].dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 5 I5 --- EvID [1087/29304] Detection ID (coinc-event-id) (G1)
7- 11 I5 --- SimID [32/48653] Simulation ID (simulation-id) (G2)
13- 20 F8.6 Msun M [1/1.4] Injected chirp mass (chirp-mass-true)
22- 26 F5.1 Mpc D [2/125] Injected distance (distance-true)
28- 35 F8.6 Msun [1/1.4] Chirp-mass posterior mean
(chirp-mass-mean) (1)
37- 44 F8.6 Msun M.5 Chirp-mass 50% credible interval (chirp-mass50) (1)
46- 53 F8.6 Msun M.9 Chirp-mass 90% credible interval (chirp-mass90) (1)
55- 59 F5.1 Mpc [6/96] Distance posterior mean (distance-mean) (1)
61- 65 F5.1 Mpc D.5 Distance 50% credible interval (distance50) (1)
67- 71 F5.1 Mpc D.9 Distance 90% credible interval (distance90) (1)
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Note (1): All parameter estimates are calculated by LALINFERENCE
(Veitch et al. 2015PhRvD..91d2003V 2015PhRvD..91d2003V).
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Global notes:
Note (G1): Identifier for detection candidate. This is the same value as
the coinceventid column in the GSTLAL output database and the OBJECT
cards in sky map FITS headers, with the 'coincevent:coincevent_id:'
prefix stripped.
Note (G2): Identifier for simulated signal. This is the same value as the
simulation_id column in the GSTLAL output database, with the
'siminspiral:simulationid:' prefix stripped.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 26-Aug-2015