LIGO-P1800344
Draft version March 21, 2019
Typeset using L
A
T
E
X
twocolumn
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Searches for Gravitational Waves from Known Pulsars at Two Harmonics in 2015–2017 LIGO Data
B. P. Abbott,
1
R. Abbott,
1
T. D. Abbott,
2
S. Abraham,
3
F. Acernese,
4, 5
K. Ackley,
6
C. Adams,
7
R. X. Adhikari,
1
V. B. Adya,
8, 9
C. Affeldt,
8, 9
M. Agathos,
10
K. Agatsuma,
11
N. Aggarwal,
12
O. D. Aguiar,
13
L. Aiello,
14, 15
A. Ain,
3
P. Ajith,
16
G. Allen,
17
A. Allocca,
18, 19
M. A. Aloy,
20
P. A. Altin,
21
A. Amato,
22
A. Ananyeva,
1
S. B. Anderson,
1
W. G. Anderson,
23
S. V. Angelova,
24
S. Antier,
25
S. Appert,
1
K. Arai,
1
M. C. Araya,
1
J. S. Areeda,
26
M. Ar
`
ene,
27
N. Arnaud,
25, 28
S. Ascenzi,
29, 30
G. Ashton,
6
S. M. Aston,
7
P. Astone,
31
F. Aubin,
32
P. Aufmuth,
9
K. AultONeal,
33
C. Austin,
2
V. Avendano,
34
A. Avila-Alvarez,
26
S. Babak,
35, 27
P. Bacon,
27
F. Badaracco,
14, 15
M. K. M. Bader,
36
S. Bae,
37
M. Bailes,
38
P. T. Baker,
39
F. Baldaccini,
40, 41
G. Ballardin,
28
S. W. Ballmer,
42
S. Banagiri,
43
J. C. Barayoga,
1
S. E. Barclay,
44
B. C. Barish,
1
D. Barker,
45
K. Barkett,
46
S. Barnum,
12
F. Barone,
4, 5
B. Barr,
44
L. Barsotti,
12
M. Barsuglia,
27
D. Barta,
47
J. Bartlett,
45
I. Bartos,
48
R. Bassiri,
49
A. Basti,
18, 19
M. Bawaj,
50, 41
J. C. Bayley,
44
M. Bazzan,
51, 52
B. B
́
ecsy,
53
M. Bejger,
27, 54
I. Belahcene,
25
A. S. Bell,
44
D. Beniwal,
55
B. K. Berger,
49
G. Bergmann,
8, 9
S. Bernuzzi,
56, 57
J. J. Bero,
58
C. P. L. Berry,
59
D. Bersanetti,
60
A. Bertolini,
36
J. Betzwieser,
7
R. Bhandare,
61
J. Bidler,
26
I. A. Bilenko,
62
S. A. Bilgili,
39
G. Billingsley,
1
J. Birch,
7
R. Birney,
24
O. Birnholtz,
58
S. Biscans,
1, 12
S. Biscoveanu,
6
A. Bisht,
9
M. Bitossi,
28, 19
M. A. Bizouard,
25
J. K. Blackburn,
1
C. D. Blair,
7
D. G. Blair,
63
R. M. Blair,
45
S. Bloemen,
64
N. Bode,
8, 9
M. Boer,
65
Y. Boetzel,
66
G. Bogaert,
65
F. Bondu,
67
E. Bonilla,
49
R. Bonnand,
32
P. Booker,
8, 9
B. A. Boom,
36
C. D. Booth,
68
R. Bork,
1
V. Boschi,
28
S. Bose,
69, 3
K. Bossie,
7
V. Bossilkov,
63
J. Bosveld,
63
Y. Bouffanais,
27
A. Bozzi,
28
C. Bradaschia,
19
P. R. Brady,
23
A. Bramley,
7
M. Branchesi,
14, 15
J. E. Brau,
70
T. Briant,
71
J. H. Briggs,
44
F. Brighenti,
72, 73
A. Brillet,
65
M. Brinkmann,
8, 9
V. Brisson,
25,
∗
P. Brockill,
23
A. F. Brooks,
1
D. D. Brown,
55
S. Brunett,
1
A. Buikema,
12
T. Bulik,
74
H. J. Bulten,
75, 36
A. Buonanno,
35, 76
D. Buskulic,
32
C. Buy,
27
R. L. Byer,
49
M. Cabero,
8, 9
L. Cadonati,
77
G. Cagnoli,
22, 78
C. Cahillane,
1
J. Calder
́
on Bustillo,
6
T. A. Callister,
1
E. Calloni,
79, 5
J. B. Camp,
80
W. A. Campbell,
6
M. Canepa,
81, 60
K. C. Cannon,
82
H. Cao,
55
J. Cao,
83
E. Capocasa,
27
F. Carbognani,
28
S. Caride,
84
M. F. Carney,
59
G. Carullo,
18
J. Casanueva Diaz,
19
C. Casentini,
29, 30
S. Caudill,
36
M. Cavagli
`
a,
85
F. Cavalier,
25
R. Cavalieri,
28
G. Cella,
19
P. Cerd
́
a-Dur
́
an,
20
G. Cerretani,
18, 19
E. Cesarini,
86, 30
O. Chaibi,
65
K. Chakravarti,
3
S. J. Chamberlin,
87
M. Chan,
44
S. Chao,
88
P. Charlton,
89
E. A. Chase,
59
E. Chassande-Mottin,
27
D. Chatterjee,
23
M. Chaturvedi,
61
B. D. Cheeseboro,
39
H. Y. Chen,
90
X. Chen,
63
Y. Chen,
46
H.-P. Cheng,
48
C. K. Cheong,
91
H. Y. Chia,
48
A. Chincarini,
60
A. Chiummo,
28
G. Cho,
92
H. S. Cho,
93
M. Cho,
76
N. Christensen,
65, 94
Q. Chu,
63
S. Chua,
71
K. W. Chung,
91
S. Chung,
63
G. Ciani,
51, 52
A. A. Ciobanu,
55
R. Ciolfi,
95, 96
F. Cipriano,
65
A. Cirone,
81, 60
F. Clara,
45
J. A. Clark,
77
P. Clearwater,
97
F. Cleva,
65
C. Cocchieri,
85
E. Coccia,
14, 15
P.-F. Cohadon,
71
D. Cohen,
25
R. Colgan,
98
M. Colleoni,
99
C. G. Collette,
100
C. Collins,
11
L. R. Cominsky,
101
M. Constancio Jr.,
13
L. Conti,
52
S. J. Cooper,
11
P. Corban,
7
T. R. Corbitt,
2
I. Cordero-Carri
́
on,
102
K. R. Corley,
98
N. Cornish,
53
A. Corsi,
84
S. Cortese,
28
C. A. Costa,
13
R. Cotesta,
35
M. W. Coughlin,
1
S. B. Coughlin,
68, 59
J.-P. Coulon,
65
S. T. Countryman,
98
P. Couvares,
1
P. B. Covas,
99
E. E. Cowan,
77
D. M. Coward,
63
M. J. Cowart,
7
D. C. Coyne,
1
R. Coyne,
103
J. D. E. Creighton,
23
T. D. Creighton,
104
J. Cripe,
2
M. Croquette,
71
S. G. Crowder,
105
T. J. Cullen,
2
A. Cumming,
44
L. Cunningham,
44
E. Cuoco,
28
T. Dal Canton,
80
G. D
́
alya,
106
S. L. Danilishin,
8, 9
S. D’Antonio,
30
K. Danzmann,
9, 8
A. Dasgupta,
107
C. F. Da Silva Costa,
48
L. E. H. Datrier,
44
V. Dattilo,
28
I. Dave,
61
M. Davier,
25
D. Davis,
42
E. J. Daw,
108
D. DeBra,
49
M. Deenadayalan,
3
J. Degallaix,
22
M. De Laurentis,
79, 5
S. Del
́
eglise,
71
W. Del Pozzo,
18, 19
L. M. DeMarchi,
59
N. Demos,
12
T. Dent,
8, 9, 109
R. De Pietri,
110, 57
J. Derby,
26
R. De Rosa,
79, 5
C. De Rossi,
22, 28
R. DeSalvo,
111
O. de Varona,
8, 9
S. Dhurandhar,
3
M. C. D
́
ıaz,
104
T. Dietrich,
36
L. Di Fiore,
5
M. Di Giovanni,
112, 96
T. Di Girolamo,
79, 5
A. Di Lieto,
18, 19
B. Ding,
100
S. Di Pace,
113, 31
I. Di Palma,
113, 31
F. Di Renzo,
18, 19
A. Dmitriev,
11
Z. Doctor,
90
F. Donovan,
12
K. L. Dooley,
68, 85
S. Doravari,
8, 9
I. Dorrington,
68
T. P. Downes,
23
M. Drago,
14, 15
J. C. Driggers,
45
Z. Du,
83
J.-G. Ducoin,
25
P. Dupej,
44
S. E. Dwyer,
45
P. J. Easter,
6
T. B. Edo,
108
M. C. Edwards,
94
A. Effler,
7
P. Ehrens,
1
J. Eichholz,
1
S. S. Eikenberry,
48
M. Eisenmann,
32
R. A. Eisenstein,
12
R. C. Essick,
90
H. Estelles,
99
D. Estevez,
32
Z. B. Etienne,
39
T. Etzel,
1
M. Evans,
12
T. M. Evans,
7
V. Fafone,
29, 30, 14
H. Fair,
42
S. Fairhurst,
68
X. Fan,
83
S. Farinon,
60
B. Farr,
70
W. M. Farr,
11
E. J. Fauchon-Jones,
68
M. Favata,
34
M. Fays,
108
M. Fazio,
114
C. Fee,
115
J. Feicht,
1
M. M. Fejer,
49
F. Feng,
27
A. Fernandez-Galiana,
12
I. Ferrante,
18, 19
E. C. Ferreira,
13
T. A. Ferreira,
13
F. Ferrini,
28
F. Fidecaro,
18, 19
I. Fiori,
28
D. Fiorucci,
27
M. Fishbach,
90
R. P. Fisher,
42, 116
J. M. Fishner,
12
M. Fitz-Axen,
43
R. Flaminio,
32, 117
M. Fletcher,
44
E. Flynn,
26
H. Fong,
118
J. A. Font,
20, 119
P. W. F. Forsyth,
21
J.-D. Fournier,
65
S. Frasca,
113, 31
F. Frasconi,
19
Z. Frei,
106
A. Freise,
11
R. Frey,
70
V. Frey,
25
P. Fritschel,
12
V. V. Frolov,
7
P. Fulda,
48
M. Fyffe,
7
H. A. Gabbard,
44
B. U. Gadre,
3
S. M. Gaebel,
11
J. R. Gair,
120
L. Gammaitoni,
40
M. R. Ganija,
55
S. G. Gaonkar,
3
lsc-spokesperson@ligo.org
virgo-spokesperson@ego-gw.it
arXiv:1902.08507v3 [astro-ph.HE] 19 Mar 2019
2
A. Garcia,
26
C. Garc
́
ıa-Quir
́
os,
99
F. Garufi,
79, 5
B. Gateley,
45
S. Gaudio,
33
G. Gaur,
121
V. Gayathri,
122
G. Gemme,
60
E. Genin,
28
A. Gennai,
19
D. George,
17
J. George,
61
L. Gergely,
123
V. Germain,
32
S. Ghonge,
77
Abhirup Ghosh,
16
Archisman Ghosh,
36
S. Ghosh,
23
B. Giacomazzo,
112, 96
J. A. Giaime,
2, 7
K. D. Giardina,
7
A. Giazotto,
19,
†
K. Gill,
33
G. Giordano,
4, 5
L. Glover,
111
P. Godwin,
87
E. Goetz,
45
R. Goetz,
48
B. Goncharov,
6
G. Gonz
́
alez,
2
J. M. Gonzalez Castro,
18, 19
A. Gopakumar,
124
M. L. Gorodetsky,
62
S. E. Gossan,
1
M. Gosselin,
28
R. Gouaty,
32
A. Grado,
125, 5
C. Graef,
44
M. Granata,
22
A. Grant,
44
S. Gras,
12
P. Grassia,
1
C. Gray,
45
R. Gray,
44
G. Greco,
72, 73
A. C. Green,
11, 48
R. Green,
68
E. M. Gretarsson,
33
P. Groot,
64
H. Grote,
68
S. Grunewald,
35
P. Gruning,
25
G. M. Guidi,
72, 73
H. K. Gulati,
107
Y. Guo,
36
A. Gupta,
87
M. K. Gupta,
107
E. K. Gustafson,
1
R. Gustafson,
126
L. Haegel,
99
O. Halim,
15, 14
B. R. Hall,
69
E. D. Hall,
12
E. Z. Hamilton,
68
G. Hammond,
44
M. Haney,
66
M. M. Hanke,
8, 9
J. Hanks,
45
C. Hanna,
87
M. D. Hannam,
68
O. A. Hannuksela,
91
J. Hanson,
7
T. Hardwick,
2
K. Haris,
16
J. Harms,
14, 15
G. M. Harry,
127
I. W. Harry,
35
C.-J. Haster,
118
K. Haughian,
44
F. J. Hayes,
44
J. Healy,
58
A. Heidmann,
71
M. C. Heintze,
7
H. Heitmann,
65
P. Hello,
25
G. Hemming,
28
M. Hendry,
44
I. S. Heng,
44
J. Hennig,
8, 9
A. W. Heptonstall,
1
Francisco Hernandez Vivanco,
6
M. Heurs,
8, 9
S. Hild,
44
T. Hinderer,
128, 36, 129
W. C. G. Ho,
130
D. Hoak,
28
S. Hochheim,
8, 9
D. Hofman,
22
A. M. Holgado,
17
N. A. Holland,
21
K. Holt,
7
D. E. Holz,
90
P. Hopkins,
68
C. Horst,
23
J. Hough,
44
E. J. Howell,
63
C. G. Hoy,
68
A. Hreibi,
65
E. A. Huerta,
17
D. Huet,
25
B. Hughey,
33
M. Hulko,
1
S. Husa,
99
S. H. Huttner,
44
T. Huynh-Dinh,
7
B. Idzkowski,
74
A. Iess,
29, 30
C. Ingram,
55
R. Inta,
84
G. Intini,
113, 31
B. Irwin,
115
H. N. Isa,
44
J.-M. Isac,
71
M. Isi,
1
B. R. Iyer,
16
K. Izumi,
45
T. Jacqmin,
71
S. J. Jadhav,
131
K. Jani,
77
N. N. Janthalur,
131
P. Jaranowski,
132
A. C. Jenkins,
133
J. Jiang,
48
D. S. Johnson,
17
A. W. Jones,
11
D. I. Jones,
134
R. Jones,
44
R. J. G. Jonker,
36
L. Ju,
63
J. Junker,
8, 9
C. V. Kalaghatgi,
68
V. Kalogera,
59
B. Kamai,
1
S. Kandhasamy,
85
G. Kang,
37
J. B. Kanner,
1
S. J. Kapadia,
23
S. Karki,
70
K. S. Karvinen,
8, 9
R. Kashyap,
16
M. Kasprzack,
1
S. Katsanevas,
28
E. Katsavounidis,
12
W. Katzman,
7
S. Kaufer,
9
K. Kawabe,
45
N. V. Keerthana,
3
F. K
́
ef
́
elian,
65
D. Keitel,
44
R. Kennedy,
108
J. S. Key,
135
F. Y. Khalili,
62
H. Khan,
26
I. Khan,
14, 30
S. Khan,
8, 9
Z. Khan,
107
E. A. Khazanov,
136
M. Khursheed,
61
N. Kijbunchoo,
21
Chunglee Kim,
137
J. C. Kim,
138
K. Kim,
91
W. Kim,
55
W. S. Kim,
139
Y.-M. Kim,
140
C. Kimball,
59
E. J. King,
55
P. J. King,
45
M. Kinley-Hanlon,
127
R. Kirchhoff,
8, 9
J. S. Kissel,
45
L. Kleybolte,
141
J. H. Klika,
23
S. Klimenko,
48
T. D. Knowles,
39
P. Koch,
8, 9
S. M. Koehlenbeck,
8, 9
G. Koekoek,
36, 142
S. Koley,
36
V. Kondrashov,
1
A. Kontos,
12
N. Koper,
8, 9
M. Korobko,
141
W. Z. Korth,
1
I. Kowalska,
74
D. B. Kozak,
1
V. Kringel,
8, 9
N. Krishnendu,
143
A. Kr
́
olak,
144, 145
G. Kuehn,
8, 9
A. Kumar,
131
P. Kumar,
146
R. Kumar,
107
S. Kumar,
16
L. Kuo,
88
A. Kutynia,
144
S. Kwang,
23
B. D. Lackey,
35
K. H. Lai,
91
T. L. Lam,
91
M. Landry,
45
B. B. Lane,
12
R. N. Lang,
147
J. Lange,
58
B. Lantz,
49
R. K. Lanza,
12
A. Lartaux-Vollard,
25
P. D. Lasky,
6
M. Laxen,
7
A. Lazzarini,
1
C. Lazzaro,
52
P. Leaci,
113, 31
S. Leavey,
8, 9
Y. K. Lecoeuche,
45
C. H. Lee,
93
H. K. Lee,
148
H. M. Lee,
149
H. W. Lee,
138
J. Lee,
92
K. Lee,
44
J. Lehmann,
8, 9
A. Lenon,
39
N. Leroy,
25
N. Letendre,
32
Y. Levin,
6, 98
J. Li,
83
K. J. L. Li,
91
T. G. F. Li,
91
X. Li,
46
F. Lin,
6
F. Linde,
36
S. D. Linker,
111
T. B. Littenberg,
150
J. Liu,
63
X. Liu,
23
R. K. L. Lo,
91, 1
N. A. Lockerbie,
24
L. T. London,
68
A. Longo,
151, 152
M. Lorenzini,
14, 15
V. Loriette,
153
M. Lormand,
7
G. Losurdo,
19
J. D. Lough,
8, 9
C. O. Lousto,
58
G. Lovelace,
26
M. E. Lower,
38
H. L
̈
uck,
9, 8
D. Lumaca,
29, 30
A. P. Lundgren,
154
R. Lynch,
12
Y. Ma,
46
R. Macas,
68
S. Macfoy,
24
M. MacInnis,
12
D. M. Macleod,
68
A. Macquet,
65
F. Maga
̃
na-Sandoval,
42
L. Maga
̃
na Zertuche,
85
R. M. Magee,
87
E. Majorana,
31
I. Maksimovic,
153
A. Malik,
61
N. Man,
65
V. Mandic,
43
V. Mangano,
44
G. L. Mansell,
45, 12
M. Manske,
23, 21
M. Mantovani,
28
F. Marchesoni,
50, 41
F. Marion,
32
S. M
́
arka,
98
Z. M
́
arka,
98
C. Markakis,
10, 17
A. S. Markosyan,
49
A. Markowitz,
1
E. Maros,
1
A. Marquina,
102
S. Marsat,
35
F. Martelli,
72, 73
I. W. Martin,
44
R. M. Martin,
34
D. V. Martynov,
11
K. Mason,
12
E. Massera,
108
A. Masserot,
32
T. J. Massinger,
1
M. Masso-Reid,
44
S. Mastrogiovanni,
113, 31
A. Matas,
43, 35
F. Matichard,
1, 12
L. Matone,
98
N. Mavalvala,
12
N. Mazumder,
69
J. J. McCann,
63
R. McCarthy,
45
D. E. McClelland,
21
S. McCormick,
7
L. McCuller,
12
S. C. McGuire,
155
J. McIver,
1
D. J. McManus,
21
T. McRae,
21
S. T. McWilliams,
39
D. Meacher,
87
G. D. Meadors,
6
M. Mehmet,
8, 9
A. K. Mehta,
16
J. Meidam,
36
A. Melatos,
97
G. Mendell,
45
R. A. Mercer,
23
L. Mereni,
22
E. L. Merilh,
45
M. Merzougui,
65
S. Meshkov,
1
C. Messenger,
44
C. Messick,
87
R. Metzdorff,
71
P. M. Meyers,
97
H. Miao,
11
C. Michel,
22
H. Middleton,
97
E. E. Mikhailov,
156
L. Milano,
79, 5
A. L. Miller,
48
A. Miller,
113, 31
M. Millhouse,
53
J. C. Mills,
68
M. C. Milovich-Goff,
111
O. Minazzoli,
65, 157
Y. Minenkov,
30
A. Mishkin,
48
C. Mishra,
158
T. Mistry,
108
S. Mitra,
3
V. P. Mitrofanov,
62
G. Mitselmakher,
48
R. Mittleman,
12
G. Mo,
94
D. Moffa,
115
K. Mogushi,
85
S. R. P. Mohapatra,
12
M. Montani,
72, 73
C. J. Moore,
10
D. Moraru,
45
G. Moreno,
45
S. Morisaki,
82
B. Mours,
32
C. M. Mow-Lowry,
11
Arunava Mukherjee,
8, 9
D. Mukherjee,
23
S. Mukherjee,
104
N. Mukund,
3
A. Mullavey,
7
J. Munch,
55
E. A. Mu
̃
niz,
42
M. Muratore,
33
P. G. Murray,
44
A. Nagar,
86, 159, 160
I. Nardecchia,
29, 30
L. Naticchioni,
113, 31
R. K. Nayak,
161
J. Neilson,
111
G. Nelemans,
64, 36
T. J. N. Nelson,
7
M. Nery,
8, 9
A. Neunzert,
126
K. Y. Ng,
12
S. Ng,
55
P. Nguyen,
70
D. Nichols,
128, 36
S. Nissanke,
128, 36
F. Nocera,
28
C. North,
68
L. K. Nuttall,
154
M. Obergaulinger,
20
J. Oberling,
45
B. D. O’Brien,
48
G. D. O’Dea,
111
G. H. Ogin,
162
J. J. Oh,
139
S. H. Oh,
139
F. Ohme,
8, 9
H. Ohta,
82
M. A. Okada,
13
M. Oliver,
99
P. Oppermann,
8, 9
Richard J. Oram,
7
B. O’Reilly,
7
R. G. Ormiston,
43
L. F. Ortega,
48
R. O’Shaughnessy,
58
S. Ossokine,
35
D. J. Ottaway,
55
H. Overmier,
7
B. J. Owen,
84
A. E. Pace,
87
G. Pagano,
18, 19
M. A. Page,
63
A. Pai,
122
S. A. Pai,
61
J. R. Palamos,
70
O. Palashov,
136
C. Palomba,
31
A. Pal-Singh,
141
Huang-Wei Pan,
88
B. Pang,
46
P. T. H. Pang,
91
C. Pankow,
59
F. Pannarale,
113, 31
B. C. Pant,
61
F. Paoletti,
19
A. Paoli,
28
A. Parida,
3
W. Parker,
7, 155
D. Pascucci,
44
A. Pasqualetti,
28
R. Passaquieti,
18, 19
D. Passuello,
19
M. Patil,
145
B. Patricelli,
18, 19
B. L. Pearlstone,
44
C. Pedersen,
68
M. Pedraza,
1
R. Pedurand,
22, 163
A. Pele,
7
S. Penn,
164
C. J. Perez,
45
A. Perreca,
112, 96
H. P. Pfeiffer,
35, 118
3
M. Phelps,
8, 9
K. S. Phukon,
3
O. J. Piccinni,
113, 31
M. Pichot,
65
F. Piergiovanni,
72, 73
G. Pillant,
28
L. Pinard,
22
M. Pirello,
45
M. Pitkin,
44
R. Poggiani,
18, 19
D. Y. T. Pong,
91
S. Ponrathnam,
3
P. Popolizio,
28
E. K. Porter,
27
J. Powell,
38
A. K. Prajapati,
107
J. Prasad,
3
K. Prasai,
49
R. Prasanna,
131
G. Pratten,
99
T. Prestegard,
23
S. Privitera,
35
G. A. Prodi,
112, 96
L. G. Prokhorov,
62
O. Puncken,
8, 9
M. Punturo,
41
P. Puppo,
31
M. P
̈
urrer,
35
H. Qi,
23
V. Quetschke,
104
P. J. Quinonez,
33
E. A. Quintero,
1
R. Quitzow-James,
70
F. J. Raab,
45
H. Radkins,
45
N. Radulescu,
65
P. Raffai,
106
S. Raja,
61
C. Rajan,
61
B. Rajbhandari,
84
M. Rakhmanov,
104
K. E. Ramirez,
104
A. Ramos-Buades,
99
Javed Rana,
3
K. Rao,
59
P. Rapagnani,
113, 31
V. Raymond,
68
M. Razzano,
18, 19
J. Read,
26
T. Regimbau,
32
L. Rei,
60
S. Reid,
24
D. H. Reitze,
1, 48
W. Ren,
17
F. Ricci,
113, 31
C. J. Richardson,
33
J. W. Richardson,
1
P. M. Ricker,
17
K. Riles,
126
M. Rizzo,
59
N. A. Robertson,
1, 44
R. Robie,
44
F. Robinet,
25
A. Rocchi,
30
L. Rolland,
32
J. G. Rollins,
1
V. J. Roma,
70
M. Romanelli,
67
R. Romano,
4, 5
C. L. Romel,
45
J. H. Romie,
7
K. Rose,
115
D. Rosi
́
nska,
165, 54
S. G. Rosofsky,
17
M. P. Ross,
166
S. Rowan,
44
A. R
̈
udiger,
8, 9,
‡
P. Ruggi,
28
G. Rutins,
167
K. Ryan,
45
S. Sachdev,
1
T. Sadecki,
45
M. Sakellariadou,
133
L. Salconi,
28
M. Saleem,
143
A. Samajdar,
36
L. Sammut,
6
E. J. Sanchez,
1
L. E. Sanchez,
1
N. Sanchis-Gual,
20
V. Sandberg,
45
J. R. Sanders,
42
K. A. Santiago,
34
N. Sarin,
6
B. Sassolas,
22
P. R. Saulson,
42
O. Sauter,
126
R. L. Savage,
45
P. Schale,
70
M. Scheel,
46
J. Scheuer,
59
P. Schmidt,
64
R. Schnabel,
141
R. M. S. Schofield,
70
A. Sch
̈
onbeck,
141
E. Schreiber,
8, 9
B. W. Schulte,
8, 9
B. F. Schutz,
68
S. G. Schwalbe,
33
J. Scott,
44
S. M. Scott,
21
E. Seidel,
17
D. Sellers,
7
A. S. Sengupta,
168
N. Sennett,
35
D. Sentenac,
28
V. Sequino,
29, 30, 14
A. Sergeev,
136
Y. Setyawati,
8, 9
D. A. Shaddock,
21
T. Shaffer,
45
M. S. Shahriar,
59
M. B. Shaner,
111
L. Shao,
35
P. Sharma,
61
P. Shawhan,
76
H. Shen,
17
R. Shink,
169
D. H. Shoemaker,
12
D. M. Shoemaker,
77
S. ShyamSundar,
61
K. Siellez,
77
M. Sieniawska,
54
D. Sigg,
45
A. D. Silva,
13
L. P. Singer,
80
N. Singh,
74
A. Singhal,
14, 31
A. M. Sintes,
99
S. Sitmukhambetov,
104
V. Skliris,
68
B. J. J. Slagmolen,
21
T. J. Slaven-Blair,
63
J. R. Smith,
26
R. J. E. Smith,
6
S. Somala,
170
E. J. Son,
139
B. Sorazu,
44
F. Sorrentino,
60
T. Souradeep,
3
E. Sowell,
84
A. P. Spencer,
44
A. K. Srivastava,
107
V. Srivastava,
42
K. Staats,
59
C. Stachie,
65
M. Standke,
8, 9
D. A. Steer,
27
M. Steinke,
8, 9
J. Steinlechner,
141, 44
S. Steinlechner,
141
D. Steinmeyer,
8, 9
S. P. Stevenson,
38
D. Stocks,
49
R. Stone,
104
D. J. Stops,
11
K. A. Strain,
44
G. Stratta,
72, 73
S. E. Strigin,
62
A. Strunk,
45
R. Sturani,
171
A. L. Stuver,
172
V. Sudhir,
12
T. Z. Summerscales,
173
L. Sun,
1
S. Sunil,
107
J. Suresh,
3
P. J. Sutton,
68
B. L. Swinkels,
36
M. J. Szczepa
́
nczyk,
33
M. Tacca,
36
S. C. Tait,
44
C. Talbot,
6
D. Talukder,
70
D. B. Tanner,
48
M. T
́
apai,
123
A. Taracchini,
35
J. D. Tasson,
94
R. Taylor,
1
F. Thies,
8, 9
M. Thomas,
7
P. Thomas,
45
S. R. Thondapu,
61
K. A. Thorne,
7
E. Thrane,
6
Shubhanshu Tiwari,
112, 96
Srishti Tiwari,
124
V. Tiwari,
68
K. Toland,
44
M. Tonelli,
18, 19
Z. Tornasi,
44
A. Torres-Forn
́
e,
174
C. I. Torrie,
1
D. T
̈
oyr
̈
a,
11
F. Travasso,
28, 41
G. Traylor,
7
M. C. Tringali,
74
A. Trovato,
27
L. Trozzo,
175, 19
R. Trudeau,
1
K. W. Tsang,
36
M. Tse,
12
R. Tso,
46
L. Tsukada,
82
D. Tsuna,
82
D. Tuyenbayev,
104
K. Ueno,
82
D. Ugolini,
176
C. S. Unnikrishnan,
124
A. L. Urban,
2
S. A. Usman,
68
H. Vahlbruch,
9
G. Vajente,
1
G. Valdes,
2
N. van Bakel,
36
M. van Beuzekom,
36
J. F. J. van den Brand,
75, 36
C. Van Den Broeck,
36, 177
D. C. Vander-Hyde,
42
J. V. van Heijningen,
63
L. van der Schaaf,
36
A. A. van Veggel,
44
M. Vardaro,
51, 52
V. Varma,
46
S. Vass,
1
M. Vas
́
uth,
47
A. Vecchio,
11
G. Vedovato,
52
J. Veitch,
44
P. J. Veitch,
55
K. Venkateswara,
166
G. Venugopalan,
1
D. Verkindt,
32
F. Vetrano,
72, 73
A. Vicer
́
e,
72, 73
A. D. Viets,
23
D. J. Vine,
167
J.-Y. Vinet,
65
S. Vitale,
12
T. Vo,
42
H. Vocca,
40, 41
C. Vorvick,
45
S. P. Vyatchanin,
62
A. R. Wade,
1
L. E. Wade,
115
M. Wade,
115
R. Walet,
36
M. Walker,
26
L. Wallace,
1
S. Walsh,
23
G. Wang,
14, 19
H. Wang,
11
J. Z. Wang,
126
W. H. Wang,
104
Y. F. Wang,
91
R. L. Ward,
21
Z. A. Warden,
33
J. Warner,
45
M. Was,
32
J. Watchi,
100
B. Weaver,
45
L.-W. Wei,
8, 9
M. Weinert,
8, 9
A. J. Weinstein,
1
R. Weiss,
12
F. Wellmann,
8, 9
L. Wen,
63
E. K. Wessel,
17
P. Weßels,
8, 9
J. W. Westhouse,
33
K. Wette,
21
J. T. Whelan,
58
B. F. Whiting,
48
C. Whittle,
12
D. M. Wilken,
8, 9
D. Williams,
44
A. R. Williamson,
128, 36
J. L. Willis,
1
B. Willke,
8, 9
M. H. Wimmer,
8, 9
W. Winkler,
8, 9
C. C. Wipf,
1
H. Wittel,
8, 9
G. Woan,
44
J. Woehler,
8, 9
J. K. Wofford,
58
J. Worden,
45
J. L. Wright,
44
D. S. Wu,
8, 9
D. M. Wysocki,
58
L. Xiao,
1
H. Yamamoto,
1
C. C. Yancey,
76
L. Yang,
114
M. J. Yap,
21
M. Yazback,
48
D. W. Yeeles,
68
Hang Yu,
12
Haocun Yu,
12
S. H. R. Yuen,
91
M. Yvert,
32
A. K. Zadro
̇
zny,
104, 144
M. Zanolin,
33
T. Zelenova,
28
J.-P. Zendri,
52
M. Zevin,
59
J. Zhang,
63
L. Zhang,
1
T. Zhang,
44
C. Zhao,
63
M. Zhou,
59
Z. Zhou,
59
X. J. Zhu,
6
M. E. Zucker,
1, 12
and J. Zweizig
1
The LIGO Scientific Collaboration and the Virgo Collaboration
Z. Arzoumanian,
178
S. Bogdanov,
179
I. Cognard,
180, 181
A. Corongiu,
182
T. Enoto,
183
P. Freire,
184
K. C. Gendreau,
178
L. Guillemot,
180, 181
A. K. Harding,
185
F. Jankowski,
186
M. J. Keith,
186
M. Kerr,
187
A. Lyne,
186
J. Palfreyman,
188
A. Possenti,
182, 189
A. Ridolfi,
184
B. Stappers,
186
G. Theureau,
180, 181, 190
and P. Weltervrede
186
1
LIGO, California Institute of Technology, Pasadena, CA 91125, USA
2
Louisiana State University, Baton Rouge, LA 70803, USA
3
Inter-University Centre for Astronomy and Astrophysics, Pune 411007, India
4
Universit`a di Salerno, Fisciano, I-84084 Salerno, Italy
5
INFN, Sezione di Napoli, Complesso Universitario di Monte S.Angelo, I-80126 Napoli, Italy
6
OzGrav, School of Physics & Astronomy, Monash University, Clayton 3800, Victoria, Australia
7
LIGO Livingston Observatory, Livingston, LA 70754, USA
8
Max Planck Institute for Gravitational Physics (Albert Einstein Institute), D-30167 Hannover, Germany
9
Leibniz Universit ̈at Hannover, D-30167 Hannover, Germany
10
University of Cambridge, Cambridge CB2 1TN, United Kingdom
11
University of Birmingham, Birmingham B15 2TT, United Kingdom
4
12
LIGO, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
13
Instituto Nacional de Pesquisas Espaciais, 12227-010 S ̃ao Jos ́e dos Campos, S ̃ao Paulo, Brazil
14
Gran Sasso Science Institute (GSSI), I-67100 L’Aquila, Italy
15
INFN, Laboratori Nazionali del Gran Sasso, I-67100 Assergi, Italy
16
International Centre for Theoretical Sciences, Tata Institute of Fundamental Research, Bengaluru 560089, India
17
NCSA, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
18
Universit`a di Pisa, I-56127 Pisa, Italy
19
INFN, Sezione di Pisa, I-56127 Pisa, Italy
20
Departamento de Astronom ́ıa y Astrof ́ısica, Universitat de Val`encia, E-46100 Burjassot, Val`encia, Spain
21
OzGrav, Australian National University, Canberra, Australian Capital Territory 0200, Australia
22
Laboratoire des Mat ́eriaux Avanc ́es (LMA), CNRS/IN2P3, F-69622 Villeurbanne, France
23
University of Wisconsin-Milwaukee, Milwaukee, WI 53201, USA
24
SUPA, University of Strathclyde, Glasgow G1 1XQ, United Kingdom
25
LAL, Univ. Paris-Sud, CNRS/IN2P3, Universit ́e Paris-Saclay, F-91898 Orsay, France
26
California State University Fullerton, Fullerton, CA 92831, USA
27
APC, AstroParticule et Cosmologie, Universit ́e Paris Diderot, CNRS/IN2P3, CEA/Irfu, Observatoire de Paris, Sorbonne Paris Cit ́e,
F-75205 Paris Cedex 13, France
28
European Gravitational Observatory (EGO), I-56021 Cascina, Pisa, Italy
29
Universit`a di Roma Tor Vergata, I-00133 Roma, Italy
30
INFN, Sezione di Roma Tor Vergata, I-00133 Roma, Italy
31
INFN, Sezione di Roma, I-00185 Roma, Italy
32
Laboratoire d’Annecy de Physique des Particules (LAPP), Univ. Grenoble Alpes, Universit ́e Savoie Mont Blanc, CNRS/IN2P3,
F-74941 Annecy, France
33
Embry-Riddle Aeronautical University, Prescott, AZ 86301, USA
34
Montclair State University, Montclair, NJ 07043, USA
35
Max Planck Institute for Gravitational Physics (Albert Einstein Institute), D-14476 Potsdam-Golm, Germany
36
Nikhef, Science Park 105, 1098 XG Amsterdam, The Netherlands
37
Korea Institute of Science and Technology Information, Daejeon 34141, South Korea
38
OzGrav, Swinburne University of Technology, Hawthorn VIC 3122, Australia
39
West Virginia University, Morgantown, WV 26506, USA
40
Universit`a di Perugia, I-06123 Perugia, Italy
41
INFN, Sezione di Perugia, I-06123 Perugia, Italy
42
Syracuse University, Syracuse, NY 13244, USA
43
University of Minnesota, Minneapolis, MN 55455, USA
44
SUPA, University of Glasgow, Glasgow G12 8QQ, United Kingdom
45
LIGO Hanford Observatory, Richland, WA 99352, USA
46
Caltech CaRT, Pasadena, CA 91125, USA
47
Wigner RCP, RMKI, H-1121 Budapest, Konkoly Thege Mikl ́os ́ut 29-33, Hungary
48
University of Florida, Gainesville, FL 32611, USA
49
Stanford University, Stanford, CA 94305, USA
50
Universit`a di Camerino, Dipartimento di Fisica, I-62032 Camerino, Italy
51
Universit`a di Padova, Dipartimento di Fisica e Astronomia, I-35131 Padova, Italy
52
INFN, Sezione di Padova, I-35131 Padova, Italy
53
Montana State University, Bozeman, MT 59717, USA
54
Nicolaus Copernicus Astronomical Center, Polish Academy of Sciences, 00-716, Warsaw, Poland
55
OzGrav, University of Adelaide, Adelaide, South Australia 5005, Australia
56
Theoretisch-Physikalisches Institut, Friedrich-Schiller-Universit ̈at Jena, D-07743 Jena, Germany
57
INFN, Sezione di Milano Bicocca, Gruppo Collegato di Parma, I-43124 Parma, Italy
58
Rochester Institute of Technology, Rochester, NY 14623, USA
59
Center for Interdisciplinary Exploration & Research in Astrophysics (CIERA), Northwestern University, Evanston, IL 60208, USA
60
INFN, Sezione di Genova, I-16146 Genova, Italy
61
RRCAT, Indore, Madhya Pradesh 452013, India
62
Faculty of Physics, Lomonosov Moscow State University, Moscow 119991, Russia
63
OzGrav, University of Western Australia, Crawley, Western Australia 6009, Australia
64
Department of Astrophysics/IMAPP, Radboud University Nijmegen, P.O. Box 9010, 6500 GL Nijmegen, The Netherlands
65
Artemis, Universit ́e Cˆote d’Azur, Observatoire Cˆote d’Azur, CNRS, CS 34229, F-06304 Nice Cedex 4, France
66
Physik-Institut, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
5
67
Univ Rennes, CNRS, Institut FOTON - UMR6082, F-3500 Rennes, France
68
Cardiff University, Cardiff CF24 3AA, United Kingdom
69
Washington State University, Pullman, WA 99164, USA
70
University of Oregon, Eugene, OR 97403, USA
71
Laboratoire Kastler Brossel, Sorbonne Universit ́e, CNRS, ENS-Universit ́e PSL, Coll`ege de France, F-75005 Paris, France
72
Universit`a degli Studi di Urbino ’Carlo Bo,’ I-61029 Urbino, Italy
73
INFN, Sezione di Firenze, I-50019 Sesto Fiorentino, Firenze, Italy
74
Astronomical Observatory Warsaw University, 00-478 Warsaw, Poland
75
VU University Amsterdam, 1081 HV Amsterdam, The Netherlands
76
University of Maryland, College Park, MD 20742, USA
77
School of Physics, Georgia Institute of Technology, Atlanta, GA 30332, USA
78
Universit ́e Claude Bernard Lyon 1, F-69622 Villeurbanne, France
79
Universit`a di Napoli ’Federico II,’ Complesso Universitario di Monte S.Angelo, I-80126 Napoli, Italy
80
NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
81
Dipartimento di Fisica, Universit`a degli Studi di Genova, I-16146 Genova, Italy
82
RESCEU, University of Tokyo, Tokyo, 113-0033, Japan.
83
Tsinghua University, Beijing 100084, China
84
Texas Tech University, Lubbock, TX 79409, USA
85
The University of Mississippi, University, MS 38677, USA
86
Museo Storico della Fisica e Centro Studi e Ricerche “Enrico Fermi”, I-00184 Roma, Italyrico Fermi, I-00184 Roma, Italy
87
The Pennsylvania State University, University Park, PA 16802, USA
88
National Tsing Hua University, Hsinchu City, 30013 Taiwan, Republic of China
89
Charles Sturt University, Wagga Wagga, New South Wales 2678, Australia
90
University of Chicago, Chicago, IL 60637, USA
91
The Chinese University of Hong Kong, Shatin, NT, Hong Kong
92
Seoul National University, Seoul 08826, South Korea
93
Pusan National University, Busan 46241, South Korea
94
Carleton College, Northfield, MN 55057, USA
95
INAF, Osservatorio Astronomico di Padova, I-35122 Padova, Italy
96
INFN, Trento Institute for Fundamental Physics and Applications, I-38123 Povo, Trento, Italy
97
OzGrav, University of Melbourne, Parkville, Victoria 3010, Australia
98
Columbia University, New York, NY 10027, USA
99
Universitat de les Illes Balears, IAC3—IEEC, E-07122 Palma de Mallorca, Spain
100
Universit ́e Libre de Bruxelles, Brussels 1050, Belgium
101
Sonoma State University, Rohnert Park, CA 94928, USA
102
Departamento de Matem ́aticas, Universitat de Val`encia, E-46100 Burjassot, Val`encia, Spain
103
University of Rhode Island, Kingston, RI 02881, USA
104
The University of Texas Rio Grande Valley, Brownsville, TX 78520, USA
105
Bellevue College, Bellevue, WA 98007, USA
106
MTA-ELTE Astrophysics Research Group, Institute of Physics, E ̈otv ̈os University, Budapest 1117, Hungary
107
Institute for Plasma Research, Bhat, Gandhinagar 382428, India
108
The University of Sheffield, Sheffield S10 2TN, United Kingdom
109
IGFAE, Campus Sur, Universidade de Santiago de Compostela, 15782 Spain
110
Dipartimento di Scienze Matematiche, Fisiche e Informatiche, Universit`a di Parma, I-43124 Parma, Italy
111
California State University, Los Angeles, 5151 State University Dr, Los Angeles, CA 90032, USA
112
Universit`a di Trento, Dipartimento di Fisica, I-38123 Povo, Trento, Italy
113
Universit`a di Roma ’La Sapienza,’ I-00185 Roma, Italy
114
Colorado State University, Fort Collins, CO 80523, USA
115
Kenyon College, Gambier, OH 43022, USA
116
Christopher Newport University, Newport News, VA 23606, USA
117
National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan
118
Canadian Institute for Theoretical Astrophysics, University of Toronto, Toronto, Ontario M5S 3H8, Canada
119
Observatori Astron`omic, Universitat de Val`encia, E-46980 Paterna, Val`encia, Spain
120
School of Mathematics, University of Edinburgh, Edinburgh EH9 3FD, United Kingdom
121
Institute Of Advanced Research, Gandhinagar 382426, India
122
Indian Institute of Technology Bombay, Powai, Mumbai 400 076, India
123
University of Szeged, D ́om t ́er 9, Szeged 6720, Hungary
6
124
Tata Institute of Fundamental Research, Mumbai 400005, India
125
INAF, Osservatorio Astronomico di Capodimonte, I-80131, Napoli, Italy
126
University of Michigan, Ann Arbor, MI 48109, USA
127
American University, Washington, D.C. 20016, USA
128
GRAPPA, Anton Pannekoek Institute for Astronomy and Institute of High-Energy Physics, University of Amsterdam, Science Park
904, 1098 XH Amsterdam, The Netherlands
129
Delta Institute for Theoretical Physics, Science Park 904, 1090 GL Amsterdam, The Netherlands
130
Department of Physics and Astronomy, Haverford College, 370 Lancaster Avenue, Haverford, PA 19041, USA
131
Directorate of Construction, Services & Estate Management, Mumbai 400094 India
132
University of Bia lystok, 15-424 Bia lystok, Poland
133
King’s College London, University of London, London WC2R 2LS, United Kingdom
134
University of Southampton, Southampton SO17 1BJ, United Kingdom
135
University of Washington Bothell, Bothell, WA 98011, USA
136
Institute of Applied Physics, Nizhny Novgorod, 603950, Russia
137
Ewha Womans University, Seoul 03760, South Korea
138
Inje University Gimhae, South Gyeongsang 50834, South Korea
139
National Institute for Mathematical Sciences, Daejeon 34047, South Korea
140
Ulsan National Institute of Science and Technology, Ulsan 44919, South Korea
141
Universit ̈at Hamburg, D-22761 Hamburg, Germany
142
Maastricht University, P.O. Box 616, 6200 MD Maastricht, The Netherlands
143
Chennai Mathematical Institute, Chennai 603103, India
144
NCBJ, 05-400
́
Swierk-Otwock, Poland
145
Institute of Mathematics, Polish Academy of Sciences, 00656 Warsaw, Poland
146
Cornell University, Ithaca, NY 14850, USA
147
Hillsdale College, Hillsdale, MI 49242, USA
148
Hanyang University, Seoul 04763, South Korea
149
Korea Astronomy and Space Science Institute, Daejeon 34055, South Korea
150
NASA Marshall Space Flight Center, Huntsville, AL 35811, USA
151
Dipartimento di Matematica e Fisica, Universit`a degli Studi Roma Tre, I-00146 Roma, Italy
152
INFN, Sezione di Roma Tre, I-00146 Roma, Italy
153
ESPCI, CNRS, F-75005 Paris, France
154
University of Portsmouth, Portsmouth, PO1 3FX, United Kingdom
155
Southern University and A&M College, Baton Rouge, LA 70813, USA
156
College of William and Mary, Williamsburg, VA 23187, USA
157
Centre Scientifique de Monaco, 8 quai Antoine Ier, MC-98000, Monaco
158
Indian Institute of Technology Madras, Chennai 600036, India
159
INFN Sezione di Torino, Via P. Giuria 1, I-10125 Torino, Italy
160
Institut des Hautes Etudes Scientifiques, F-91440 Bures-sur-Yvette, France
161
IISER-Kolkata, Mohanpur, West Bengal 741252, India
162
Whitman College, 345 Boyer Avenue, Walla Walla, WA 99362 USA
163
Universit ́e de Lyon, F-69361 Lyon, France
164
Hobart and William Smith Colleges, Geneva, NY 14456, USA
165
Janusz Gil Institute of Astronomy, University of Zielona G ́ora, 65-265 Zielona G ́ora, Poland
166
University of Washington, Seattle, WA 98195, USA
167
SUPA, University of the West of Scotland, Paisley PA1 2BE, United Kingdom
168
Indian Institute of Technology, Gandhinagar Ahmedabad Gujarat 382424, India
169
Universit ́e de Montr ́eal/Polytechnique, Montreal, Quebec H3T 1J4, Canada
170
Indian Institute of Technology Hyderabad, Sangareddy, Khandi, Telangana 502285, India
171
International Institute of Physics, Universidade Federal do Rio Grande do Norte, Natal RN 59078-970, Brazil
172
Villanova University, 800 Lancaster Ave, Villanova, PA 19085, USA
173
Andrews University, Berrien Springs, MI 49104, USA
174
Max Planck Institute for Gravitationalphysik (Albert Einstein Institute), D-14476 Potsdam-Golm, Germany
175
Universit`a di Siena, I-53100 Siena, Italy
176
Trinity University, San Antonio, TX 78212, USA
177
Van Swinderen Institute for Particle Physics and Gravity, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The
Netherlands
178
X-Ray Astrophysics Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
7
179
Columbia Astrophysics Laboratory, Columbia University, 550 West 120th Street, New York, NY, 10027, USA
180
Laboratoire de Physique et Chimie de l’Environnement et de l’Espace – Universit ́e d’Orl ́eans / CNRS, F-45071 Orl ́eans Cedex 02,
France
181
Station de Radioastronomie de Nan ̧cay, Observatoire de Paris, CNRS/INSU, F-18330 Nan ̧cay, France
182
INAF–Osservatorio Astronomico di Cagliari, via della Scienza 5, 09047 Selargius, Italy
183
Hakubi Center for Advanced Research and Department of Astronomy, Kyoto University, Kyoto 606-8302, Japan
184
Max-Planck-Institut f ̈ur Radioastronomie, Auf dem H ̈ugel 69, D-53121 Bonn, Germany
185
Astrophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
186
Jodrell Bank Centre for Astrophysics, School of Physics and Astronomy, University of Manchester, Manchester, M13 9PL, UK
187
Space Science Division, Naval Research Laboratory, Washington, DC 20375-5352, USA
188
Department of Physical Sciences, University of Tasmania, Private Bag 37, Hobart, Tasmania 7001, Australia
189
Universit`a di Cagliari, Dipartimento di Fisica, I-09042, Monserrato, Italy
190
LUTH, Observatoire de Paris, PSL Research University, CNRS, Universit ́e Paris Diderot, Sorbonne Paris Cit ́e, F-92195 Meudon,
France
(Dated: March 21, 2019)
ABSTRACT
We present a search for gravitational waves from 222 pulsars with rotation frequencies
&
10 Hz. We
use advanced LIGO data from its first and second observing runs spanning 2015–2017, which provides
the highest sensitivity gravitational-wave data so far obtained. In this search we target emission from
both the
l
=
m
= 2 mass quadrupole mode, with a frequency at twice that of the pulsar’s rotation,
and from the
l
= 2,
m
= 1 mode, with a frequency at the pulsar rotation frequency. The search finds
no evidence for gravitational-wave emission from any pulsar at either frequency. For the
l
=
m
= 2
mode search, we provide updated upper limits on the gravitational-wave amplitude, mass quadrupole
moment, and fiducial ellipticity for 167 pulsars, and the first such limits for a further 55. For 20 young
pulsars these results give limits that surpass those inferred from the pulsars’ spin-down. For the Crab
and Vela pulsars our results constrain gravitational-wave emission to account for less than 0.017% and
0.18% of the spin-down luminosity, respectively. For the recycled millisecond pulsar J0711
−
6830 our
limits are only a factor of 1.3 above the spin-down limit, assuming the canonical value of 10
38
kg m
2
for
the star’s moment of inertia, and imply a gravitational-wave derived upper limit on the star’s ellipticity
of 1
.
2
×
10
−
8
. We also place new limits on the emission amplitude at the rotation frequency of the
pulsars.
Keywords:
pulsars: general — stars: neutron — gravitational waves
1.
INTRODUCTION
There have been several previous searches for persis-
tent (or continuous) quasi-monochromatic gravitational
waves emitted by a selection of known pulsars using
data from the LIGO, Virgo, and GEO600 gravitational-
wave detectors (Abbott et al. 2004, 2005, 2007, 2008,
2010; Abadie et al. 2011; Aasi et al. 2014; Abbott et al.
2017a). In the majority of these, the signals that have
been searched for are those that would be expected from
stars with a non-zero
l
=
m
= 2 mass quadrupole mo-
ment
Q
22
and with polarization content consistent with
the expectations of General Relativity (see, e.g., Zim-
mermann & Szedenits 1979; Bonazzola & Gourgoulhon
∗
Deceased, February 2018.
†
Deceased, November 2017.
‡
Deceased, July 2018.
1996; Jaranowski et al. 1998). Such signals would be
produced at twice the stellar rotation frequencies, and
searches have generally assumed that the rotation fre-
quency derived from electromagnetic observations of the
pulsars is phase locked to the star’s rotation and thus
the gravitational-wave signal. Some searches have been
performed where the assumption of the phase locking to
the observed electromagnetic signal has been slightly re-
laxed, allowing the signal to be potentially offset over a
small range of frequencies (
∼
10
−
100 mHz) and first fre-
quency derivatives (Abbott et al. 2008; Aasi et al. 2015a;
Abbott et al. 2017b). A search including the prospect
of the signal’s polarization content deviating from the
purely tensorial modes predicted by General Relativity
has also been performed in Abbott et al. (2018a). None
of these searches have detected a gravitational-wave sig-
nal from any of the pulsars that were targeted. Thus,
8
stringent upper limits of the gravitational-wave ampli-
tude, mass quadrupole moment, and ellipticity have
been set.
Emission of gravitational waves at a pulsar’s rotation
frequency from the
l
= 2,
m
= 1 harmonic mode, in ad-
dition to emission at twice the rotation frequency from
the
l
=
m
= 2 mode, has long been theorized (Zim-
mermann & Szedenits 1979; Zimmermann 1980; Jones
& Andersson 2002). The fiducial emission mechanism
would be from a biaxial, or triaxial star, undergoing free
precession. In the case of a precessing biaxial star, or
a precessing triaxial star with a small “wobble angle”,
the electromagnetic pulsar emission frequency would be
modulated slightly, with the gravitational-wave emission
being emitted at frequencies close to once and twice the
time-averaged rotation frequency. There is only weak
observational evidence for any pulsar showing precession
(see the discussions in, e.g., Jones 2012; Durant et al.
2013, and references therein), and
free
precession would
be quickly damped, but as shown in Jones (2010) the
existence of a superfluid interior gives rise to the pos-
sibility for gravitational-wave emission at the rotation
frequency even for a non-precessing star. A search for
emission at both once and twice the rotation frequency
for 43 pulsars using data from LIGO’s fifth science run
has been performed in Pitkin et al. (2015). That analy-
sis saw no evidence for signals at the rotation frequency
and was consistent with the search conducted for signals
purely from the
l
=
m
= 2 mode (Abbott et al. 2010).
The searches implemented in this work are specifically
designed for the case where the signal’s phase evolution
is very well known over the course of full gravitational-
wave detector observing runs. Therefore, here we will
only focus on the assumption that emission occurs at
precisely once and twice the observed rotation frequency,
as given by the model in Jones (2010), so we do not ac-
count for the possibility of any of the sources undergoing
free precession.
Previous searches, combining the results given in Aasi
et al. (2014) and Abbott et al. (2017a), have included
a total of 271 pulsars. The most stringent upper limit
on gravitational-wave amplitude from the
l
=
m
= 2
mode was set for PSR J1918
−
0642 at 1
.
6
×
10
−
26
, and
the most stringent upper limit on the fiducial elliptic-
ity (see Appendix A, Equations (A2) and (A4)) was
set for PSR J0636+5129 at 1
.
3
×
10
−
8
(Abbott et al.
2017a). However, for these particular pulsars, both of
which are millisecond pulsars (MSPs), the gravitational-
wave amplitude limits are above the fiducial spin-down
limit (see Appendix A and Equation (A7)). The obser-
vational limits in Abbott et al. (2017a) showed 8 pulsars
for which the fiducial spin-down limit was surpassed,
with the upper limits on emission from the Crab pulsar
(PSR J0534+2200) and Vela pulsar (PSR J0835
−
4510)
being factors of more than 20 and 9 below their respec-
tive spin-down limits.
Concurrently with this work, a search has been per-
formed for 33 pulsars using advanced LIGO data from
the second observing run in which the assumption of
phase locking between the electromagnetically-observed
signal and gravitational-wave signal is relaxed by allow-
ing the signal model to vary freely over a narrow band
of frequencies and frequency derivatives (Abbott et al.
2019). Even with the slight sensitivity decrease com-
pared to the analysis presented here, due to the wider
parameter space, that analysis surpasses the spin-down
limit for 13 of the pulsars.
1.1.
Signal model
Using the formalism shown in Jones (2015); Pitkin
et al. (2015) the gravitational-wave waveform from the
l
= 2,
m
= 1 harmonic mode can be written as
h
21
(
t
) =
−
C
21
2
[
F
D
+
(
α,δ,ψ
;
t
) sin
ι
cos
ι
cos
(
Φ(
t
) + Φ
C
21
)
+
F
D
×
(
α,δ,ψ
;
t
) sin
ι
sin
(
Φ(
t
) + Φ
C
21
)]
,
(1)
and that from the
l
=
m
= 2 mode can be written as
h
22
(
t
) =
−
C
22
[
F
D
+
(
α,δ,ψ
;
t
)
(
1 + cos
2
ι
)
cos
(
2Φ(
t
) + Φ
C
22
)
+ 2
F
D
×
(
α,δ,ψ
;
t
) cos
ι
sin
(
2Φ(
t
) + Φ
C
22
)]
.
(2)
Here,
C
21
and
C
22
represent the amplitudes of the com-
ponents, Φ
C
21
and Φ
C
22
represent initial phases at a par-
ticular epoch, Φ(
t
) is the rotational phase of the source,
and
ι
is the inclination of the source’s rotation axis
with respect to the line-of-sight.
1
The detected ampli-
tude is modulated by the detector response functions
for the two polarizations of the signal (‘+’ and ‘
×
’),
1
For precessing stars the phase evolution Φ(
t
) in Equations (1)
and (2) will not necessarily be given by the rotational phase, but
can differ by the precession frequency.