Binary Black Hole Mergers in the First Advanced LIGO Observing Run
B. P. Abbott,
1
R. Abbott,
1
T. D. Abbott,
2
M. R. Abernathy,
3
F. Acernese,
4,5
K. Ackley,
6
C. Adams,
7
T. Adams,
8
P. Addesso,
9
R. X. Adhikari,
1
V. B. Adya,
10
C. Affeldt,
10
M. Agathos,
11
K. Agatsuma,
11
N. Aggarwal,
12
O. D. Aguiar,
13
L. Aiello,
14,15
A. Ain,
16
P. Ajith,
17
B. Allen,
10,18,19
A. Allocca,
20,21
P. A. Altin,
22
S. B. Anderson,
1
W. G. Anderson,
18
K. Arai,
1
M. C. Araya,
1
C. C. Arceneaux,
23
J. S. Areeda,
24
N. Arnaud,
25
K. G. Arun,
26
S. Ascenzi,
27,15
G. Ashton,
28
M. Ast,
29
S. M. Aston,
7
P. Astone,
30
P. Aufmuth,
19
C. Aulbert,
10
S. Babak,
31
P. Bacon,
32
M. K. M. Bader,
11
P. T. Baker,
33
F. Baldaccini,
34,35
G. Ballardin,
36
S. W. Ballmer,
37
J. C. Barayoga,
1
S. E. Barclay,
38
B. C. Barish,
1
D. Barker,
39
F. Barone,
4,5
B. Barr,
38
L. Barsotti,
12
M. Barsuglia,
32
D. Barta,
40
J. Bartlett,
39
I. Bartos,
41
R. Bassiri,
42
A. Basti,
20,21
J. C. Batch,
39
C. Baune,
10
V. Bavigadda,
36
M. Bazzan,
43,44
M. Bejger,
45
A. S. Bell,
38
B. K. Berger,
1
G. Bergmann,
10
C. P. L. Berry,
46
D. Bersanetti,
47,48
A. Bertolini,
11
J. Betzwieser,
7
S. Bhagwat,
37
R. Bhandare,
49
I. A. Bilenko,
50
G. Billingsley,
1
J. Birch,
7
R. Birney,
51
O. Birnholtz,
10
S. Biscans,
12
A. Bisht,
10,19
M. Bitossi,
36
C. Biwer,
37
M. A. Bizouard,
25
J. K. Blackburn,
1
C. D. Blair,
52
D. G. Blair,
52
R. M. Blair,
39
S. Bloemen,
53
O. Bock,
10
M. Boer,
54
G. Bogaert,
54
C. Bogan,
10
A. Bohe,
31
C. Bond,
46
F. Bondu,
55
R. Bonnand,
8
B. A. Boom,
11
R. Bork,
1
V. Boschi,
20,21
S. Bose,
56,16
Y. Bouffanais,
32
A. Bozzi,
36
C. Bradaschia,
21
P. R. Brady,
18
V. B. Braginsky,
50
,
†
M. Branchesi,
57,58
J. E. Brau,
59
T. Briant,
60
A. Brillet,
54
M. Brinkmann,
10
V. Brisson,
25
P. Brockill,
18
J. E. Broida,
61
A. F. Brooks,
1
D. A. Brown,
37
D. D. Brown,
46
N. M. Brown,
12
S. Brunett,
1
C. C. Buchanan,
2
A. Buikema,
12
T. Bulik,
62
H. J. Bulten,
63,11
A. Buonanno,
31,64
D. Buskulic,
8
C. Buy,
32
R. L. Byer,
42
M. Cabero,
10
L. Cadonati,
65
G. Cagnoli,
66,67
C. Cahillane,
1
J. Calderón Bustillo,
65
T. Callister,
1
E. Calloni,
68,5
J. B. Camp,
69
K. C. Cannon,
70
J. Cao,
71
C. D. Capano,
10
E. Capocasa,
32
F. Carbognani,
36
S. Caride,
72
J. Casanueva Diaz,
25
C. Casentini,
27,15
S. Caudill,
18
M. Cavaglià,
23
F. Cavalier,
25
R. Cavalieri,
36
G. Cella,
21
C. B. Cepeda,
1
L. Cerboni Baiardi,
57,58
G. Cerretani,
20,21
E. Cesarini,
27,15
S. J. Chamberlin,
73
M. Chan,
38
S. Chao,
74
P. Charlton,
75
E. Chassande-Mottin,
32
B. D. Cheeseboro,
76
H. Y. Chen,
77
Y. Chen,
78
C. Cheng,
74
A. Chincarini,
48
A. Chiummo,
36
H. S. Cho,
79
M. Cho,
64
J. H. Chow,
22
N. Christensen,
61
Q. Chu,
52
S. Chua,
60
S. Chung,
52
G. Ciani,
6
F. Clara,
39
J. A. Clark,
65
F. Cleva,
54
E. Coccia,
27,14
P.-F. Cohadon,
60
A. Colla,
80,30
C. G. Collette,
81
L. Cominsky,
82
M. Constancio, Jr.,
13
A. Conte,
80,30
L. Conti,
44
D. Cook,
39
T. R. Corbitt,
2
N. Cornish,
33
A. Corsi,
72
S. Cortese,
36
C. A. Costa,
13
M. W. Coughlin,
61
S. B. Coughlin,
83
J.-P. Coulon,
54
S. T. Countryman,
41
P. Couvares,
1
E. E. Cowan,
65
D. M. Coward,
52
M. J. Cowart,
7
D. C. Coyne,
1
R. Coyne,
72
K. Craig,
38
J. D. E. Creighton,
18
J. Cripe,
2
S. G. Crowder,
84
A. Cumming,
38
L. Cunningham,
38
E. Cuoco,
36
T. Dal Canton,
10
S. L. Danilishin,
38
S. D
’
Antonio,
15
K. Danzmann,
19,10
N. S. Darman,
85
A. Dasgupta,
86
C. F. Da Silva Costa,
6
V. Dattilo,
36
I. Dave,
49
M. Davier,
25
G. S. Davies,
38
E. J. Daw,
87
R. Day,
36
S. De,
37
D. DeBra,
42
G. Debreczeni,
40
J. Degallaix,
66
M. De Laurentis,
68,5
S. Deléglise,
60
W. Del Pozzo,
46
T. Denker,
10
T. Dent,
10
V. Dergachev,
1
R. De Rosa,
68,5
R. T. DeRosa,
7
R. DeSalvo,
9
R. C. Devine,
76
S. Dhurandhar,
16
M. C. Díaz,
88
L. Di Fiore,
5
M. Di Giovanni,
89,90
T. Di Girolamo,
68,5
A. Di Lieto,
20,21
S. Di Pace,
80,30
I. Di Palma,
31,80,30
A. Di Virgilio,
21
V. Dolique,
66
F. Donovan,
12
K. L. Dooley,
23
S. Doravari,
10
R. Douglas,
38
T. P. Downes,
18
M. Drago,
10
R. W. P. Drever,
1
J. C. Driggers,
39
M. Ducrot,
8
S. E. Dwyer,
39
T. B. Edo,
87
M. C. Edwards,
61
A. Effler,
7
H.-B. Eggenstein,
10
P. Ehrens,
1
J. Eichholz,
6,1
S. S. Eikenberry,
6
W. Engels,
78
R. C. Essick,
12
T. Etzel,
1
M. Evans,
12
T. M. Evans,
7
R. Everett,
73
M. Factourovich,
41
V. Fafone,
27,15
H. Fair,
37
S. Fairhurst,
91
X. Fan,
71
Q. Fang,
52
S. Farinon,
48
B. Farr,
77
W. M. Farr,
46
M. Favata,
92
M. Fays,
91
H. Fehrmann,
10
M. M. Fejer,
42
E. Fenyvesi,
93
I. Ferrante,
20,21
E. C. Ferreira,
13
F. Ferrini,
36
F. Fidecaro,
20,21
I. Fiori,
36
D. Fiorucci,
32
R. P. Fisher,
37
R. Flaminio,
66,94
M. Fletcher,
38
H. Fong,
95
J.-D. Fournier,
54
S. Frasca,
80,30
F. Frasconi,
21
Z. Frei,
93
A. Freise,
46
R. Frey,
59
V. Frey,
25
P. Fritschel,
12
V. V. Frolov,
7
P. Fulda,
6
M. Fyffe,
7
H. A. G. Gabbard,
23
S. Gaebel,
46
J. R. Gair,
96
L. Gammaitoni,
34
S. G. Gaonkar,
16
F. Garufi,
68,5
G. Gaur,
97,86
N. Gehrels,
69
G. Gemme,
48
P. Geng,
88
E. Genin,
36
A. Gennai,
21
J. George,
49
L. Gergely,
98
V. Germain,
8
Abhirup Ghosh,
17
Archisman Ghosh,
17
S. Ghosh,
53,11
J. A. Giaime,
2,7
K. D. Giardina,
7
A. Giazotto,
21
K. Gill,
99
A. Glaefke,
38
E. Goetz,
39
R. Goetz,
6
L. Gondan,
93
G. González,
2
J. M. Gonzalez Castro,
20,21
A. Gopakumar,
100
N. A. Gordon,
38
M. L. Gorodetsky,
50
S. E. Gossan,
1
M. Gosselin,
36
R. Gouaty,
8
A. Grado,
101,5
C. Graef,
38
P. B. Graff,
64
M. Granata,
66
A. Grant,
38
S. Gras,
12
C. Gray,
39
G. Greco,
57,58
A. C. Green,
46
P. Groot,
53
H. Grote,
10
S. Grunewald,
31
G. M. Guidi,
57,58
X. Guo,
71
A. Gupta,
16
M. K. Gupta,
86
K. E. Gushwa,
1
E. K. Gustafson,
1
R. Gustafson,
102
J. J. Hacker,
24
B. R. Hall,
56
E. D. Hall,
1
H. Hamilton,
103
G. Hammond,
38
M. Haney,
100
M. M. Hanke,
10
J. Hanks,
39
C. Hanna,
73
M. D. Hannam,
91
J. Hanson,
7
T. Hardwick,
2
J. Harms,
57,58
G. M. Harry,
3
I. W. Harry,
31
M. J. Hart,
38
M. T. Hartman,
6
C.-J. Haster,
46
K. Haughian,
38
J. Healy,
104
A. Heidmann,
60
M. C. Heintze,
7
H. Heitmann,
54
P. Hello,
25
G. Hemming,
36
M. Hendry,
38
I. S. Heng,
38
J. Hennig,
38
J. Henry,
104
A. W. Heptonstall,
1
M. Heurs,
10,19
S. Hild,
38
D. Hoak,
36
D. Hofman,
66
K. Holt,
7
D. E. Holz,
77
P. Hopkins,
91
J. Hough,
38
E. A. Houston,
38
E. J. Howell,
52
Y. M. Hu,
10
S. Huang,
74
E. A. Huerta,
105
D. Huet,
25
B. Hughey,
99
S. Husa,
106
S. H. Huttner,
38
T. Huynh-Dinh,
7
N. Indik,
10
D. R. Ingram,
39
R. Inta,
72
H. N. Isa,
38
J.-M. Isac,
60
M. Isi,
1
T. Isogai,
12
B. R. Iyer,
17
K. Izumi,
39
T. Jacqmin,
60
H. Jang,
79
K. Jani,
65
P. Jaranowski,
107
S. Jawahar,
108
L. Jian,
52
F. Jiménez-Forteza,
106
W. W. Johnson,
2
N. K. Johnson-McDaniel,
17
D. I. Jones,
28
R. Jones,
38
R. J. G. Jonker,
11
L. Ju,
52
Haris K,
109
PHYSICAL REVIEW X
6,
041015 (2016)
2160-3308
=
16
=
6(4)
=
041015(36)
041015-1
Published by the American Physical Society
C. V. Kalaghatgi,
91
V. Kalogera,
83
S. Kandhasamy,
23
G. Kang,
79
J. B. Kanner,
1
S. J. Kapadia,
10
S. Karki,
59
K. S. Karvinen,
10
M. Kasprzack,
36,2
E. Katsavounidis,
12
W. Katzman,
7
S. Kaufer,
19
T. Kaur,
52
K. Kawabe,
39
F. Kéfélian,
54
M. S. Kehl,
95
D. Keitel,
106
D. B. Kelley,
37
W. Kells,
1
R. Kennedy,
87
J. S. Key,
88
F. Y. Khalili,
50
I. Khan,
14
S. Khan,
91
Z. Khan,
86
E. A. Khazanov,
110
N. Kijbunchoo,
39
Chi-Woong Kim,
79
Chunglee Kim,
79
J. Kim,
111
K. Kim,
112
N. Kim,
42
W. Kim,
113
Y.-M. Kim,
111
S. J. Kimbrell,
65
E. J. King,
113
P. J. King,
39
J. S. Kissel,
39
B. Klein,
83
L. Kleybolte,
29
S. Klimenko,
6
S. M. Koehlenbeck,
10
S. Koley,
11
V. Kondrashov,
1
A. Kontos,
12
M. Korobko,
29
W. Z. Korth,
1
I. Kowalska,
62
D. B. Kozak,
1
V. Kringel,
10
B. Krishnan,
10
A. Królak,
114,115
C. Krueger,
19
G. Kuehn,
10
P. Kumar,
95
R. Kumar,
86
L. Kuo,
74
A. Kutynia,
114
B. D. Lackey,
37
M. Landry,
39
J. Lange,
104
B. Lantz,
42
P. D. Lasky,
116
M. Laxen,
7
A. Lazzarini,
1
C. Lazzaro,
44
P. Leaci,
80,30
S. Leavey,
38
E. O. Lebigot,
32,71
C. H. Lee,
111
H. K. Lee,
112
H. M. Lee,
117
K. Lee,
38
A. Lenon,
37
M. Leonardi,
89,90
J. R. Leong,
10
N. Leroy,
25
N. Letendre,
8
Y. Levin,
116
J. B. Lewis,
1
T. G. F. Li,
118
A. Libson,
12
T. B. Littenberg,
119
N. A. Lockerbie,
108
A. L. Lombardi,
120
L. T. London,
91
J. E. Lord,
37
M. Lorenzini,
14,15
V. Loriette,
121
M. Lormand,
7
G. Losurdo,
58
J. D. Lough,
10,19
C. Lousto,
104
H. Lück,
19,10
A. P. Lundgren,
10
R. Lynch,
12
Y. Ma,
52
B. Machenschalk,
10
M. MacInnis,
12
D. M. Macleod,
2
F. Magaña-Sandoval,
37
L. Magaña Zertuche,
37
R. M. Magee,
56
E. Majorana,
30
I. Maksimovic,
121
V. Malvezzi,
27,15
N. Man,
54
I. Mandel,
46
V. Mandic,
84
V. Mangano,
38
G. L. Mansell,
22
M. Manske,
18
M. Mantovani,
36
F. Marchesoni,
122,35
F. Marion,
8
S. Márka,
41
Z. Márka,
41
A. S. Markosyan,
42
E. Maros,
1
F. Martelli,
57,58
L. Martellini,
54
I. W. Martin,
38
D. V. Martynov,
12
J. N. Marx,
1
K. Mason,
12
A. Masserot,
8
T. J. Massinger,
37
M. Masso-Reid,
38
S. Mastrogiovanni,
80,30
F. Matichard,
12
L. Matone,
41
N. Mavalvala,
12
N. Mazumder,
56
R. McCarthy,
39
D. E. McClelland,
22
S. McCormick,
7
S. C. McGuire,
123
G. McIntyre,
1
J. McIver,
1
D. J. McManus,
22
T. McRae,
22
S. T. McWilliams,
76
D. Meacher,
73
G. D. Meadors,
31,10
J. Meidam,
11
A. Melatos,
85
G. Mendell,
39
R. A. Mercer,
18
E. L. Merilh,
39
M. Merzougui,
54
S. Meshkov,
1
C. Messenger,
38
C. Messick,
73
R. Metzdorff,
60
P. M. Meyers,
84
F. Mezzani,
30,80
H. Miao,
46
C. Michel,
66
H. Middleton,
46
E. E. Mikhailov,
124
L. Milano,
68,5
A. L. Miller,
6,80,30
A. Miller,
83
B. B. Miller,
83
J. Miller,
12
M. Millhouse,
33
Y. Minenkov,
15
J. Ming,
31
S. Mirshekari,
125
C. Mishra,
17
S. Mitra,
16
V. P. Mitrofanov,
50
G. Mitselmakher,
6
R. Mittleman,
12
A. Moggi,
21
M. Mohan,
36
S. R. P. Mohapatra,
12
M. Montani,
57,58
B. C. Moore,
92
C. J. Moore,
126
D. Moraru,
39
G. Moreno,
39
S. R. Morriss,
88
K. Mossavi,
10
B. Mours,
8
C. M. Mow-Lowry,
46
G. Mueller,
6
A. W. Muir,
91
Arunava Mukherjee,
17
D. Mukherjee,
18
S. Mukherjee,
88
N. Mukund,
16
A. Mullavey,
7
J. Munch,
113
D. J. Murphy,
41
P. G. Murray,
38
A. Mytidis,
6
I. Nardecchia,
27,15
L. Naticchioni,
80,30
R. K. Nayak,
127
K. Nedkova,
120
G. Nelemans,
53,11
T. J. N. Nelson,
7
M. Neri,
47,48
A. Neunzert,
102
G. Newton,
38
T. T. Nguyen,
22
A. B. Nielsen,
10
S. Nissanke,
53,11
A. Nitz,
10
F. Nocera,
36
D. Nolting,
7
M. E. N. Normandin,
88
L. K. Nuttall,
37
J. Oberling,
39
E. Ochsner,
18
J. O
’
Dell,
128
E. Oelker,
12
G. H. Ogin,
129
J. J. Oh,
130
S. H. Oh,
130
F. Ohme,
91
M. Oliver,
106
P. Oppermann,
10
Richard J. Oram,
7
B. O
’
Reilly,
7
R. O
’
Shaughnessy,
104
D. J. Ottaway,
113
H. Overmier,
7
B. J. Owen,
72
A. Pai,
109
S. A. Pai,
49
J. R. Palamos,
59
O. Palashov,
110
C. Palomba,
30
A. Pal-Singh,
29
H. Pan,
74
Y. Pan,
64
C. Pankow,
83
F. Pannarale,
91
B. C. Pant,
49
F. Paoletti,
36,21
A. Paoli,
36
M. A. Papa,
31,18,10
H. R. Paris,
42
W. Parker,
7
D. Pascucci,
38
A. Pasqualetti,
36
R. Passaquieti,
20,21
D. Passuello,
21
B. Patricelli,
20,21
Z. Patrick,
42
B. L. Pearlstone,
38
M. Pedraza,
1
R. Pedurand,
66,131
L. Pekowsky,
37
A. Pele,
7
S. Penn,
132
A. Perreca,
1
L. M. Perri,
83
H. P. Pfeiffer,
95
M. Phelps,
38
O. J. Piccinni,
80,30
M. Pichot,
54
F. Piergiovanni,
57,58
V. Pierro,
9
G. Pillant,
36
L. Pinard,
66
I. M. Pinto,
9
M. Pitkin,
38
M. Poe,
18
R. Poggiani,
20,21
P. Popolizio,
36
E. Porter,
32
A. Post,
10
J. Powell,
38
J. Prasad,
16
V. Predoi,
91
T. Prestegard,
84
L. R. Price,
1
M. Prijatelj,
10,36
M. Principe,
9
S. Privitera,
31
R. Prix,
10
G. A. Prodi,
89,90
L. Prokhorov,
50
O. Puncken,
10
M. Punturo,
35
P. Puppo,
30
M. Pürrer,
31
H. Qi,
18
J. Qin,
52
S. Qiu,
116
V. Quetschke,
88
E. A. Quintero,
1
R. Quitzow-James,
59
F. J. Raab,
39
D. S. Rabeling,
22
H. Radkins,
39
P. Raffai,
93
S. Raja,
49
C. Rajan,
49
M. Rakhmanov,
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P. Rapagnani,
80,30
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M. Razzano,
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V. Re,
27
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T. Regimbau,
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et al.
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,
†
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and J. Zweizig
1
(LIGO Scientific Collaboration and Virgo Collaboration)
*
1
LIGO, California Institute of Technology, Pasadena, California 91125, USA
2
Louisiana State University, Baton Rouge, Louisiana 70803, USA
3
American University, Washington, D.C. 20016, USA
4
Università di Salerno, Fisciano, I-84084 Salerno, Italy
5
INFN, Sezione di Napoli, Complesso Universitario di Monte S.Angelo, I-80126 Napoli, Italy
6
University of Florida, Gainesville, Florida 32611, USA
7
LIGO Livingston Observatory, Livingston, Louisiana 70754, USA
8
Laboratoire d
’
Annecy-le-Vieux de Physique des Particules (LAPP), Université Savoie Mont Blanc,
CNRS/IN2P3, F-74941 Annecy-le-Vieux, France
9
University of Sannio at Benevento, I-82100 Benevento, Italy
and INFN, Sezione di Napoli, I-80100 Napoli, Italy
10
Albert-Einstein-Institut, Max-Planck-Institut für Gravitationsphysik, D-30167 Hannover, Germany
11
Nikhef, Science Park, 1098 XG Amsterdam, The Netherlands
12
LIGO, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
13
Instituto Nacional de Pesquisas Espaciais, 12227-010 São José dos Campos, São Paulo, Brazil
14
INFN, Gran Sasso Science Institute, I-67100L
’
Aquila, Italy
15
INFN, Sezione di Roma Tor Vergata, I-00133 Roma, Italy
16
Inter-University Centre for Astronomy and Astrophysics, Pune 411007, India
17
International Centre for Theoretical Sciences, Tata Institute of Fundamental Research,
Bangalore 560012, India
18
University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53201, USA
19
Leibniz Universität Hannover, D-30167 Hannover, Germany
20
Università di Pisa, I-56127 Pisa, Italy
21
INFN, Sezione di Pisa, I-56127 Pisa, Italy
22
Australian National University, Canberra, Australian Capital Territory 0200, Australia
23
The University of Mississippi, University, Mississippi 38677, USA
24
California State University Fullerton, Fullerton, California 92831, USA
25
LAL, Université Paris-Sud, CNRS/IN2P3, Université Paris-Saclay, F-91898 Orsay, France
26
Chennai Mathematical Institute, Chennai 603103, India
27
Università di Roma Tor Vergata, I-00133 Roma, Italy
28
University of Southampton, Southampton SO17 1BJ, United Kingdom
29
Universität Hamburg, D-22761 Hamburg, Germany
30
INFN, Sezione di Roma, I-00185 Roma, Italy
31
Albert-Einstein-Institut, Max-Planck-Institut für Gravitations-physik, D-14476 Potsdam-Golm, Germany
32
APC, AstroParticule et Cosmologie, Université Paris Diderot, CNRS/IN2P3,
CEA/Irfu, Observatoire de Paris, Sorbonne Paris Cité, F-75205 Paris Cedex 13, France
33
Montana State University, Bozeman, Montana 59717, USA
34
Università di Perugia, I-06123 Perugia, Italy
35
INFN, Sezione di Perugia, I-06123 Perugia, Italy
36
European Gravitational Observatory (EGO), I-56021 Cascina, Pisa, Italy
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...
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37
Syracuse University, Syracuse, New York 13244, USA
38
SUPA, University of Glasgow, Glasgow G12 8QQ, United Kingdom
39
LIGO Hanford Observatory, Richland, Washington 99352, USA
40
Wigner RCP, RMKI, H-1121 Budapest, Konkoly Thege Miklós út 29-33, Hungary
41
Columbia University, New York, New York 10027, USA
42
Stanford University, Stanford, California 94305, USA
43
Università di Padova, Dipartimento di Fisica e Astronomia, I-35131 Padova, Italy
44
INFN, Sezione di Padova, I-35131 Padova, Italy
45
CAMK-PAN, 00-716 Warsaw, Poland
46
University of Birmingham, Birmingham B15 2TT, United Kingdom
47
Università degli Studi di Genova, I-16146 Genova, Italy
48
INFN, Sezione di Genova, I-16146 Genova, Italy
49
RRCAT, Indore, Madhya Pradesh 452013, India
50
Faculty of Physics, Lomonosov Moscow State University, Moscow 119991, Russia
51
SUPA, University of the West of Scotland, Paisley PA1 2BE, United Kingdom
52
University of Western Australia, Crawley, Western Australia 6009, Australia
53
Department of Astrophysics/IMAPP, Radboud University Nijmegen,
P.O. Box 9010, 6500 GL Nijmegen, The Netherlands
54
Artemis,Université Côted
’
Azur,CNRS,ObservatoireCôted
’
Azur,CS34229,F-06304 Nicecedex4,France
55
Institut de Physique de Rennes, CNRS, Université de Rennes 1, F-35042 Rennes, France
56
Washington State University, Pullman, Washington 99164, USA
57
Università degli Studi di Urbino
“
Carlo Bo
”
, I-61029 Urbino, Italy
58
INFN, Sezione di Firenze, I-50019 Sesto Fiorentino, Firenze, Italy
59
University of Oregon, Eugene, Oregon 97403, USA
60
Laboratoire Kastler Brossel, UPMC-Sorbonne Universités, CNRS, ENS-PSL Research University,
Collège de France, F-75005 Paris, France
61
Carleton College, Northfield, Minnesota 55057, USA
62
Astronomical Observatory Warsaw University, 00-478 Warsaw, Poland
63
VU University Amsterdam, 1081 HV Amsterdam, The Netherlands
64
University of Maryland, College Park, Maryland 20742, USA
65
Center for Relativistic Astrophysics and School of Physics, Georgia Institute of Technology,
Atlanta, Georgia 30332, USA
66
Laboratoire des Matériaux Avancés (LMA), CNRS/IN2P3, F-69622 Villeurbanne, France
67
Université Claude Bernard Lyon 1, F-69622 Villeurbanne, France
68
Università di Napoli
“
Federico II
”
, Complesso Universitario di Monte S.Angelo, I-80126 Napoli, Italy
69
NASA/Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
70
RESCEU, University of Tokyo, Tokyo 113-0033, Japan
71
Tsinghua University, Beijing 100084, China
72
Texas Tech University, Lubbock, Texas 79409, USA
73
The Pennsylvania State University, University Park, Pennsylvania 16802, USA
74
National Tsing Hua University, Hsinchu City, 30013 Taiwan, Republic of China
75
Charles Sturt University, Wagga Wagga, New South Wales 2678, Australia
76
West Virginia University, Morgantown, West Virginia 26506, USA
77
University of Chicago, Chicago, Illinois 60637, USA
78
Caltech CaRT, Pasadena, California 91125, USA
79
Korea Institute of Science and Technology Information, Daejeon 305-806, Korea
80
Università di Roma
“
La Sapienza
”
, I-00185 Roma, Italy
81
University of Brussels, Brussels 1050, Belgium
82
Sonoma State University, Rohnert Park, California 94928, USA
83
Center for Interdisciplinary Exploration & Research in Astrophysics (CIERA),
Northwestern University, Evanston, Illinois 60208, USA
84
University of Minnesota, Minneapolis, Minnesota 55455, USA
85
The University of Melbourne, Parkville, Victoria 3010, Australia
86
Institute for Plasma Research, Bhat, Gandhinagar 382428, India
87
The University of Sheffield, Sheffield S10 2TN, United Kingdom
88
The University of Texas Rio Grande Valley, Brownsville, Texas 78520, USA
89
Università di Trento, Dipartimento di Fisica, I-38123 Povo, Trento, Italy
90
INFN, Trento Institute for Fundamental Physics and Applications, I-38123 Povo, Trento, Italy
91
Cardiff University, Cardiff CF24 3AA, United Kingdom
92
Montclair State University, Montclair, New Jersey 07043, USA
B. P. ABBOTT
et al.
PHYS. REV. X
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93
MTA Eötvös University,
“
Lendulet
”
Astrophysics Research Group, Budapest 1117, Hungary
94
National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan
95
Canadian Institute for Theoretical Astrophysics, University of Toronto, Toronto, Ontario M5S 3H8, Canada
96
School of Mathematics, University of Edinburgh, Edinburgh EH9 3FD, United Kingdom
97
Indian Institute of Technology, Gandhinagar, Ahmedabad, Gujarat 382424, India
98
University of Szeged, Dóm tér 9, Szeged 6720, Hungary
99
Embry-Riddle Aeronautical University, Prescott, Arizona 86301, USA
100
Tata Institute of Fundamental Research, Mumbai 400005, India
101
INAF, Osservatorio Astronomico di Capodimonte, I-80131 Napoli, Italy
102
University of Michigan, Ann Arbor, Michigan 48109, USA
103
Abilene Christian University, Abilene, Texas 79699, USA
104
Rochester Institute of Technology, Rochester, New York 14623, USA
105
NCSA, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
106
Universitat de les Illes Balears, IAC3
—
IEEC, E-07122 Palma de Mallorca, Spain
107
University of Bia
ł
ystok, 15-424 Bia
ł
ystok, Poland
108
SUPA, University of Strathclyde, Glasgow G1 1XQ, United Kingdom
109
IISER-TVM, CET Campus, Trivandrum Kerala 695016, India
110
Institute of Applied Physics, Nizhny Novgorod 603950, Russia
111
Pusan National University, Busan 609-735, Korea
112
Hanyang University, Seoul 133-791, Korea
113
University of Adelaide, Adelaide, South Australia 5005, Australia
114
NCBJ, 05-400
Ś
wierk-Otwock, Poland
115
IM-PAN, 00-956 Warsaw, Poland
116
Monash University, Victoria 3800, Australia
117
Seoul National University, Seoul 151-742, Korea
118
The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
119
University of Alabama in Huntsville, Huntsville, Alabama 35899, USA
120
University of Massachusetts-Amherst, Amherst, Massachusetts 01003, USA
121
ESPCI, CNRS, F-75005 Paris, France
122
Università di Camerino, Dipartimento di Fisica, I-62032 Camerino, Italy
123
Southern University and A&M College, Baton Rouge, Louisiana 70813, USA
124
College of William and Mary, Williamsburg, Virginia 23187, USA
125
Instituto de Física Teórica, University Estadual Paulista/ICTP South American Institute for
Fundamental Research, São Paulo, São Paulo 01140-070, Brazil
126
University of Cambridge, Cambridge CB2 1TN, United Kingdom
127
IISER-Kolkata, Mohanpur, West Bengal 741252, India
128
Rutherford Appleton Laboratory, HSIC, Chilton, Didcot, Oxon OX11 0QX, United Kingdom
129
Whitman College, 345 Boyer Avenue, Walla Walla, Washington 99362, USA
130
National Institute for Mathematical Sciences, Daejeon 305-390, Korea
131
Université de Lyon, F-69361 Lyon, France
132
Hobart and William Smith Colleges, Geneva, New York 14456, USA
133
Janusz Gil Institute of Astronomy, University of Zielona Góra, 65-265 Zielona Góra, Poland
134
King
’
s College London, University of London, London WC2R 2LS, United Kingdom
135
Andrews University, Berrien Springs, Michigan 49104, USA
136
Università di Siena, I-53100 Siena, Italy
137
Trinity University, San Antonio, Texas 78212, USA
138
University of Washington, Seattle, Washington 98195, USA
139
Kenyon College, Gambier, Ohio 43022, USA
(Received 24 June 2016; revised manuscript received 8 August 2016; published 21 October 2016)
The first observational run of the Advanced LIGO detectors, from September 12, 2015 to January 19,
2016, saw the first detections of gravitational waves from binary black hole mergers. In this paper, we
present full results from a search for binary black hole merger signals with total masses up to
100
M
⊙
and
detailed implications from our observations of these systems. Our search, based on general-relativistic
*
Full author list given at the end of the article.
†
Deceased.
Published by the American Physical Society under the terms of the
Creative Commons Attribution 3.0 License
. Further distribution of
this work must maintain attribution to the author(s) and the published article
’
s title, journal citation, and DOI.
BINARY BLACK HOLE MERGERS IN THE FIRST
...
PHYS. REV. X
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041015-5
models of gravitational-wave signals from binary black hole systems, unambiguously identified two
signals, GW150914 and GW151226, with a significance of greater than
5
σ
over the observing period. It
also identified a third possible signal, LVT151012, with substantially lower significance and with an 87%
probability of being of astrophysical origin. We provide detailed estimates of the parameters of the
observed systems. Both GW150914 and GW151226 provide an unprecedented opportunity to study the
two-body motion of a compact-object binary in the large velocity, highly nonlinear regime. We do not
observe any deviations from general relativity, and we place improved empirical bounds on several high-
order post-Newtonian coefficients. From our observations, we infer stellar-mass binary black hole merger
rates lying in the range
9
–
240
Gpc
−
3
yr
−
1
. These observations are beginning to inform astrophysical
predictions of binary black hole formation rates and indicate that future observing runs of the Advanced
detector network will yield many more gravitational-wave detections.
DOI:
10.1103/PhysRevX.6.041015
Subject Areas: Gravitation
I. INTRODUCTION
The first observing run (O1) of the Advanced LIGO
detectors took place from September 12, 2015, to January
19, 2016. The detectors provided unprecedented sensitivity
to gravitational waves over a range of frequencies from
30 Hz to several kHz
[1]
, which covers the frequencies of
gravitational waves emitted during the late inspiral, merger,
and ringdown of stellar-mass binary black holes (BBHs). In
this paper, we report the results of a matched-filter search
using relativistic models of BBH waveforms during the
whole of the first Advanced LIGO observing run. The
compact binary coalescence (CBC) search targets gravita-
tional-wave emission from compact-object binaries with
individual masses from
1
M
⊙
to
99
M
⊙
, total mass less than
100
M
⊙
, and dimensionless spins up to 0.99. Here, we
report on results of the search for BBHs. The search was
performed using two independently implemented analyses,
referred to as PyCBC
[2
–
4]
and GstLAL
[5
–
7]
. These
analyses use a common set of template waveforms
[8
–
10]
but differ in their implementations of matched filtering
[11,12]
, their use of detector data-quality information
[13]
,
the techniques used to mitigate the effect of non-Gaussian
noise transients in the detector
[5,14]
, and the methods for
estimating the noise background of the search
[3,15]
.We
obtain results that are consistent between the two analyses.
The search identified two BBH mergers: GW150914,
observed on September 14, 2015 at 09
∶
50:45 UTC
[16]
,
and GW151226, observed on December 26, 2015 at
03
∶
38:53 UTC
[17]
. Both of these signals were observed
with a significance greater than
5
σ
. In addition, a third
candidate event, LVT151012, consistent with a BBH
merger was observed on October 12, 2015 at 09
∶
54:43
UTC with a significance of
≲
2
σ
. Although LVT151012 is
not significant enough to claim an unambiguous detection,
it is more likely to have resulted from a gravitational-wave
signal than from an instrumental or environmental noise
transient. The key parameters of the events are summarized
in Table
I
.
The properties of the sources can be inferred from the
observed gravitational waveforms. In particular, the binary
evolution, which is encoded in the phasing of the gravi-
tational-wave signal, is governed by the masses and spins
of the binary components. The sky location of the source is
primarily determined through time of arrival differences at
the two Advanced LIGO sites. The observed amplitudes
and relative phase of the signal in the two Advanced LIGO
detectors can be used to further restrict the sky location and
infer the distance to the source and the binary orientation.
We provide a detailed evaluation of the source properties
and inferred parameters of GW150914, GW151226, and
LVT151012. We use models of the waveform covering the
inspiral, merger, and ringdown phases based on combining
post-Newtonian (PN) theory
[19
–
24]
, the effective-one-
body (EOB) formalism
[25
–
29]
, and numerical relativity
simulations
[30
–
36]
. One model is restricted to spins
aligned with the orbital angular momentum
[8,9]
, while
the other allows for nonaligned orientation of the spins,
which can lead to precession of the orbital plane
[37,38]
.
The parameters of GW150914 have been reported pre-
viously in Refs.
[39,40]
. We provide revised results which
make use of updated instrumental calibration.
The emitted signals depend upon the strong field
dynamics of general relativity; thus, our observations
provide an extraordinary opportunity to test the predictions
of general relativity for binary coalescence waveforms.
Several tests of general relativity were performed using
GW150914, as described in Ref.
[41]
. One of these was a
parametrized test for the consistency of the observed
waveform with a general-relativity-based model. We per-
form a similar test on GW151226. Since this source is of
lower mass than GW150914, the observed waveform lasts
for many more cycles in the detector data, allowing us to
better constrain the PN coefficients that describe the
evolution of the binary through the inspiral phase. In
addition, we combine the results from GW150914 and
GW151226 to place still tighter bounds on deviations from
general relativity.
The observed events begin to reveal a population of
stellar-mass black hole mergers. We use these signals to
constrain the rates of BBH mergers in the universe and
B. P. ABBOTT
et al.
PHYS. REV. X
6,
041015 (2016)
041015-6
begin to probe the mass distribution of black hole mergers.
The inferred rates are consistent with those derived from
GW150914
[42]
. We also discuss the astrophysical impli-
cations of the observations and the prospects for future
Advanced LIGO and Virgo observing runs.
The results presented here are restricted to BBH systems
with total masses less than
100
M
⊙
. Searches for compact
binary systems containing neutron stars are presented in
Ref.
[43]
, and searches for more massive black holes and
unmodeled transient signals will be reported elsewhere.
This paper is organized as follows: Section
II
provides
an overview of the Advanced LIGO detectors during
the first observing run, as well as the data used in the
search. Section
III
presents the results of the search,
details of the two gravitational-wave events, GW150914
and GW151226, and the candidate event LVT151012.
Section
IV
provides detailed parameter-estimation results
for the events. Section
V
presents results for the consistency
of the two events, GW150914 and GW151226, with the
predictions of general relativity. Section
VI
presents the
inferred rate of stellar-mass BBH mergers, and Sec.
VII
discusses the implications of these observations and future
prospects. We include appendixes that provide additional
technical details of the methods used. Appendix
A
describes
the CBC search, with
A1
and
A2
presenting details of the
construction and tuning of the two independently imple-
mented analyses used in the search, highlighting differences
from the methods described in Ref.
[44]
. Appendix
B
provides a description of the parameter-estimation analysis
and includes a summary table of results for all three events.
Appendixes
C
and
D
provide details of the methods used to
infer merger rates and mass distributions, respectively.
II. OVERVIEW OF THE INSTRUMENTS
AND DATA SET
The two Advanced LIGO detectors, one located in
Hanford, Washington (H1) and one in Livingston,
Louisiana (L1), are modified Michelson interferometers
with 4-km-long arms. The interferometer mirrors act as test
masses, and the passage of a gravitational wave induces a
differential arm length change which is proportional to the
gravitational-wave strain amplitude. The Advanced LIGO
detectors came online in September 2015 after a major
upgrade targeting a tenfold improvement in sensitivity over
the initial LIGO detectors
[45]
. While not yet operating at
design sensitivity, both detectors reached an instrument
noise 3
–
4 times lower than ever measured before in their
most sensitive frequency band between 100 Hz and 300 Hz
[1]
. The corresponding observable volume of space for
BBH mergers, in the mass range reported in this paper, was
about 30 times greater, enabling the successful search
reported here.
The typical instrument noise of the Advanced LIGO
detectors during O1 is described in detail in Ref.
[46]
. In the
left panel of Fig.
1
, we show the amplitude spectral density
of the total strain noise of both detectors,
ffiffiffiffiffiffiffiffiffi
S
ð
f
Þ
p
, calibrated
in units of strain per
ffiffiffiffiffiffi
Hz
p
[47]
. Overlaid on the noise curves
TABLE I. Details of the three most significant events. The false alarm rate, p-value, and significance are from the PyCBC analysis; the
GstLAL results are consistent with this. For source parameters, we report median values with 90% credible intervals that include
statistical errors, and systematic errors from averaging the results of different waveform models. The uncertainty for the peak luminosity
includes an estimate of additional error from the fitting formula. The sky localization is the area of the 90% credible area. Masses are
given in the source frame; to convert to the detector frame, multiply by (
1
þ
z
). The source redshift assumes standard cosmology
[18]
.
Event
GW150914
GW151226
LVT151012
Signal-to-noise ratio
ρ
23.7
13.0
9.7
False alarm rate FAR
=
yr
−
1
<
6
.
0
×
10
−
7
<
6
.
0
×
10
−
7
0.37
p-value
7
.
5
×
10
−
8
7
.
5
×
10
−
8
0.045
Significance
>
5
.
3
σ
>
5
.
3
σ
1
.
7
σ
Primary mass
m
source
1
=
M
⊙
36
.
2
þ
5
.
2
−
3
.
8
14
.
2
þ
8
.
3
−
3
.
7
23
þ
18
−
6
Secondary mass
m
source
2
=
M
⊙
29
.
1
þ
3
.
7
−
4
.
4
7
.
5
þ
2
.
3
−
2
.
3
13
þ
4
−
5
Chirp mass
M
source
=
M
⊙
28
.
1
þ
1
.
8
−
1
.
5
8
.
9
þ
0
.
3
−
0
.
3
15
.
1
þ
1
.
4
−
1
.
1
Total mass
M
source
=
M
⊙
65
.
3
þ
4
.
1
−
3
.
4
21
.
8
þ
5
.
9
−
1
.
7
37
þ
13
−
4
Effective inspiral spin
χ
eff
−
0
.
06
þ
0
.
14
−
0
.
14
0
.
21
þ
0
.
20
−
0
.
10
0
.
0
þ
0
.
3
−
0
.
2
Final mass
M
source
f
=
M
⊙
62
.
3
þ
3
.
7
−
3
.
1
20
.
8
þ
6
.
1
−
1
.
7
35
þ
14
−
4
Final spin
a
f
0
.
68
þ
0
.
05
−
0
.
06
0
.
74
þ
0
.
06
−
0
.
06
0
.
66
þ
0
.
09
−
0
.
10
Radiated energy
E
rad
=
ð
M
⊙
c
2
Þ
3
.
0
þ
0
.
5
−
0
.
4
1
.
0
þ
0
.
1
−
0
.
2
1
.
5
þ
0
.
3
−
0
.
4
Peak luminosity
l
peak
=
ð
erg s
−
1
Þ
3
.
6
þ
0
.
5
−
0
.
4
×
10
56
3
.
3
þ
0
.
8
−
1
.
6
×
10
56
3
.
1
þ
0
.
8
−
1
.
8
×
10
56
Luminosity distance
D
L
=
Mpc
420
þ
150
−
180
440
þ
180
−
190
1000
þ
500
−
500
Source redshift
z
0
.
09
þ
0
.
03
−
0
.
04
0
.
09
þ
0
.
03
−
0
.
04
0
.
20
þ
0
.
09
−
0
.
09
Sky localization
ΔΩ
=
deg
2
230
850
1600
BINARY BLACK HOLE MERGERS IN THE FIRST
...
PHYS. REV. X
6,
041015 (2016)
041015-7
of the detectors, the waveforms of GW150914,
GW151226, and LVT151012 are also shown. The expected
signal-to-noise ratio (SNR)
ρ
of a signal,
h
ð
t
Þ
, can be
expressed as
ρ
2
¼
Z
∞
0
ð
2
j
~
h
ð
f
Þj
ffiffiffi
f
p
Þ
2
S
n
ð
f
Þ
dln
ð
f
Þ
;
ð
1
Þ
where
~
h
ð
f
Þ
is the Fourier transform of the signal. Writing it
in this form motivates the normalization of the waveform
plotted in Fig.
1
, as the area between the signal and noise
curves is indicative of the SNR of the events.
The gravitational-wave signal from a BBH merger takes
the form of a chirp, increasing in frequency and amplitude
as the black holes spiral inwards. The amplitude of the
signal is maximum at the merger, after which it decays
rapidly as the final black hole rings down to equilibrium. In
the frequency domain, the amplitude decreases with fre-
quency during inspiral, as the signal spends a greater
number of cycles at lower frequencies. This is followed
by a slower falloff during merger and then a steep decrease
during the ringdown. The amplitude of GW150914 is
significantly larger than the other two events, and at the
time of the merger, the gravitational-wave signal lies well
above the noise. GW151226 has a lower amplitude but
sweeps across the whole detector
’
s sensitive band up to
nearly 800 Hz. The corresponding time series of the three
waveforms are plotted in the right panel of Fig.
1
to better
visualize the difference in duration within the Advanced
LIGO band: GW150914 lasts only a few cycles, while
LVT151012 and GW151226 have lower amplitudes but last
longer.
The analysis presented in this paper includes the total set
of O1 data from September 12, 2015 to January 19, 2016,
which contain a total coincident analysis time of 51.5 days
accumulated when both detectors were operating in their
normal state. As discussed in Ref.
[13]
with regard to the
first 16 days of O1 data, the output data of both detectors
typically contain nonstationary and non-Gaussian features,
in the form of transient noise artifacts of varying durations.
Longer duration artifacts, such as nonstationary behavior in
the interferometer noise, are not very detrimental to CBC
searches as they occur on a time scale that is much longer
than any CBC waveform. However, shorter duration
artifacts can pollute the noise background distribution of
CBC searches. Many of these artifacts have distinct
signatures
[49]
visible in the auxiliary data channels from
the large number of sensors used to monitor instrumental or
environmental disturbances at each observatory site
[50]
.
When a significant noise source is identified, contaminated
data are removed from the analysis data set. After applying
this data quality process, detailed in Ref.
[51]
, the remain-
ing coincident analysis time in O1 is 48.6 days. The
analyses search only stretches of data longer than a
minimum duration, to ensure that the detectors are operat-
ing stably. The choice is different in the two analyses and
reduces the available data to 46.1 days for the PyCBC
analysis and 48.3 days for the GstLAL analysis.
III. SEARCH RESULTS
Two different, largely independent, analyses have been
implemented to search for stellar-mass BBH signals in the
data of O1: PyCBC
[2
–
4]
and GstLAL
[5
–
7]
. Both these
analyses employ matched filtering
[52
–
60]
with waveforms
given by models based on general relativity
[8,9]
to search
for gravitational waves from binary neutron stars, BBHs,
and neutron star
–
black hole binaries. In this paper, we
focus on the results of the matched-filter search for BBHs.
FIG. 1. Left panel: Amplitude spectral density of the total strain noise of the H1 and L1 detectors,
ffiffiffiffiffiffiffiffiffi
S
ð
f
Þ
p
, in units of strain per
ffiffiffiffiffiffi
Hz
p
,
and the recovered signals of GW150914, GW151226, and LVT151012 plotted so that the relative amplitudes can be related to the SNR
of the signal (as described in the text). Right panel: Time evolution of the recovered signals from when they enter the detectors
’
sensitive
band at 30 Hz. Both figures show the 90% credible regions of the LIGO Hanford signal reconstructions from a coherent Bayesian
analysis using a nonprecessing spin waveform model
[48]
.
B. P. ABBOTT
et al.
PHYS. REV. X
6,
041015 (2016)
041015-8