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Draft version April 5, 2017
Preprint typeset using L
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FIRST SEARCH FOR GRAVITATIONAL WAVES FROM KNOWN PULSARS WITH ADVANCED LIGO
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
A. Ananyeva,
1
S. B. Anderson,
1
W. G. Anderson,
18
S. Appert,
1
K. Arai,
1
M. C. Araya,
1
J. S. Areeda,
23
N. Arnaud,
24
K. G. Arun,
25
S. Ascenzi,
26,15
G. Ashton,
10
M. Ast,
27
S. M. Aston,
7
P. Astone,
28
P. Aufmuth,
19
C. Aulbert,
10
A. Avila-Alvarez,
23
S. Babak,
29
P. Bacon,
30
M. K. M. Bader,
11
P. T. Baker,
31
F. Baldaccini,
32,33
G. Ballardin,
34
S. W. Ballmer,
35
J. C. Barayoga,
1
S. E. Barclay,
36
B. C. Barish,
1
D. Barker,
37
F. Barone,
4,5
B. Barr,
36
L. Barsotti,
12
M. Barsuglia,
30
D. Barta,
38
J. Bartlett,
37
I. Bartos,
39
R. Bassiri,
40
A. Basti,
20,21
J. C. Batch,
37
C. Baune,
10
V. Bavigadda,
34
M. Bazzan,
41,42
C. Beer,
10
M. Bejger,
43
I. Belahcene,
24
M. Belgin,
44
A. S. Bell,
36
B. K. Berger,
1
G. Bergmann,
10
C. P. L. Berry,
45
D. Bersanetti,
46,47
A. Bertolini,
11
J. Betzwieser,
7
S. Bhagwat,
35
R. Bhandare,
48
I. A. Bilenko,
49
G. Billingsley,
1
C. R. Billman,
6
J. Birch,
7
R. Birney,
50
O. Birnholtz,
10
S. Biscans,
12,1
A. Bisht,
19
M. Bitossi,
34
C. Biwer,
35
M. A. Bizouard,
24
J. K. Blackburn,
1
J. Blackman,
51
C. D. Blair,
52
D. G. Blair,
52
R. M. Blair,
37
S. Bloemen,
53
O. Bock,
10
M. Boer,
54
G. Bogaert,
54
A. Bohe,
29
F. Bondu,
55
R. Bonnand,
8
B. A. Boom,
11
R. Bork,
1
V. Boschi,
20,21
S. Bose,
56,16
Y. Bouffanais,
30
A. Bozzi,
34
C. Bradaschia,
21
P. R. Brady,
18
V. B. Braginsky
,
49
M. Branchesi,
57,58
J. E. Brau,
59
T. Briant,
60
A. Brillet,
54
M. Brinkmann,
10
V. Brisson,
24
P. Brockill,
18
J. E. Broida,
61
A. F. Brooks,
1
D. A. Brown,
35
D. D. Brown,
45
N. M. Brown,
12
S. Brunett,
1
C. C. Buchanan,
2
A. Buikema,
12
T. Bulik,
62
H. J. Bulten,
63,11
A. Buonanno,
29,64
D. Buskulic,
8
C. Buy,
30
R. L. Byer,
40
M. Cabero,
10
L. Cadonati,
44
G. Cagnoli,
65,66
C. Cahillane,
1
J. Calder
́
on Bustillo,
44
T. A. Callister,
1
E. Calloni,
67,5
J. B. Camp,
68
M. Canepa,
46,47
K. C. Cannon,
69
H. Cao,
70
J. Cao,
71
C. D. Capano,
10
E. Capocasa,
30
F. Carbognani,
34
S. Caride,
72
J. Casanueva Diaz,
24
C. Casentini,
26,15
S. Caudill,
18
M. Cavagli
`
a,
73
F. Cavalier,
24
R. Cavalieri,
34
G. Cella,
21
C. B. Cepeda,
1
L. Cerboni Baiardi,
57,58
G. Cerretani,
20,21
E. Cesarini,
26,15
S. J. Chamberlin,
74
M. Chan,
36
S. Chao,
75
P. Charlton,
76
E. Chassande-Mottin,
30
B. D. Cheeseboro,
31
H. Y. Chen,
77
Y. Chen,
51
H.-P. Cheng,
6
A. Chincarini,
47
A. Chiummo,
34
T. Chmiel,
78
H. S. Cho,
79
M. Cho,
64
J. H. Chow,
22
N. Christensen,
61
Q. Chu,
52
A. J. K. Chua,
80
S. Chua,
60
S. Chung,
52
G. Ciani,
6
F. Clara,
37
J. A. Clark,
44
F. Cleva,
54
C. Cocchieri,
73
E. Coccia,
14,15
P.-F. Cohadon,
60
A. Colla,
81,28
C. G. Collette,
82
L. Cominsky,
83
M. Constancio Jr.,
13
L. Conti,
42
S. J. Cooper,
45
T. R. Corbitt,
2
N. Cornish,
84
A. Corsi,
72
S. Cortese,
34
C. A. Costa,
13
M. W. Coughlin,
61
S. B. Coughlin,
85
J.-P. Coulon,
54
S. T. Countryman,
39
P. Couvares,
1
P. B. Covas,
86
E. E. Cowan,
44
D. M. Coward,
52
M. J. Cowart,
7
D. C. Coyne,
1
R. Coyne,
72
J. D. E. Creighton,
18
T. D. Creighton,
87
J. Cripe,
2
S. G. Crowder,
88
T. J. Cullen,
23
A. Cumming,
36
L. Cunningham,
36
E. Cuoco,
34
T. Dal Canton,
68
S. L. Danilishin,
36
S. D’Antonio,
15
K. Danzmann,
19,10
A. Dasgupta,
89
C. F. Da Silva Costa,
6
V. Dattilo,
34
I. Dave,
48
M. Davier,
24
G. S. Davies,
36
D. Davis,
35
E. J. Daw,
90
B. Day,
44
R. Day,
34
S. De,
35
D. DeBra,
40
G. Debreczeni,
38
J. Degallaix,
65
M. De Laurentis,
67,5
S. Del
́
eglise,
60
W. Del Pozzo,
45
T. Denker,
10
T. Dent,
10
V. Dergachev,
29
R. De Rosa,
67,5
R. T. DeRosa,
7
R. DeSalvo,
91
J. Devenson,
50
R. C. Devine,
31
S. Dhurandhar,
16
M. C. D
́
ıaz,
87
L. Di Fiore,
5
M. Di Giovanni,
92,93
T. Di Girolamo,
67,5
A. Di Lieto,
20,21
S. Di Pace,
81,28
I. Di Palma,
29,81,28
A. Di Virgilio,
21
Z. Doctor,
77
V. Dolique,
65
F. Donovan,
12
K. L. Dooley,
73
S. Doravari,
10
I. Dorrington,
94
R. Douglas,
36
M. Dovale
́
Alvarez,
45
T. P. Downes,
18
M. Drago,
10
R. W. P. Drever,
1
J. C. Driggers,
37
Z. Du,
71
M. Ducrot,
8
S. E. Dwyer,
37
T. B. Edo,
90
M. C. Edwards,
61
A. Effler,
7
H.-B. Eggenstein,
10
P. Ehrens,
1
J. Eichholz,
1
S. S. Eikenberry,
6
R. A. Eisenstein,
12
R. C. Essick,
12
Z. Etienne,
31
T. Etzel,
1
M. Evans,
12
T. M. Evans,
7
R. Everett,
74
M. Factourovich,
39
V. Fafone,
26,15,14
H. Fair,
35
S. Fairhurst,
94
X. Fan,
71
S. Farinon,
47
B. Farr,
77
W. M. Farr,
45
E. J. Fauchon-Jones,
94
M. Favata,
95
M. Fays,
94
H. Fehrmann,
10
M. M. Fejer,
40
A. Fern
́
andez Galiana,
12
I. Ferrante,
20,21
E. C. Ferreira,
13
F. Ferrini,
34
F. Fidecaro,
20,21
I. Fiori,
34
D. Fiorucci,
30
R. P. Fisher,
35
R. Flaminio,
65,96
M. Fletcher,
36
H. Fong,
97
S. S. Forsyth,
44
J.-D. Fournier,
54
S. Frasca,
81,28
F. Frasconi,
21
Z. Frei,
98
A. Freise,
45
R. Frey,
59
V. Frey,
24
E. M. Fries,
1
P. Fritschel,
12
V. V. Frolov,
7
P. Fulda,
6,68
M. Fyffe,
7
H. Gabbard,
10
B. U. Gadre,
16
S. M. Gaebel,
45
J. R. Gair,
99
L. Gammaitoni,
32
S. G. Gaonkar,
16
F. Garufi,
67,5
G. Gaur,
100
V. Gayathri,
101
N. Gehrels,
68
G. Gemme,
47
E. Genin,
34
A. Gennai,
21
J. George,
48
L. Gergely,
102
V. Germain,
8
S. Ghonge,
17
Abhirup Ghosh,
17
Archisman Ghosh,
11,17
S. Ghosh,
53,11
J. A. Giaime,
2,7
K. D. Giardina,
7
A. Giazotto,
21
K. Gill,
103
A. Glaefke,
36
E. Goetz,
10
R. Goetz,
6
L. Gondan,
98
G. Gonz
́
alez,
2
J. M. Gonzalez Castro,
20,21
A. Gopakumar,
104
M. L. Gorodetsky,
49
S. E. Gossan,
1
M. Gosselin,
34
R. Gouaty,
8
A. Grado,
105,5
C. Graef,
36
M. Granata,
65
A. Grant,
36
S. Gras,
12
C. Gray,
37
G. Greco,
57,58
A. C. Green,
45
P. Groot,
53
H. Grote,
10
S. Grunewald,
29
G. M. Guidi,
57,58
X. Guo,
71
A. Gupta,
16
M. K. Gupta,
89
K. E. Gushwa,
1
E. K. Gustafson,
1
R. Gustafson,
106
J. J. Hacker,
23
B. R. Hall,
56
E. D. Hall,
1
G. Hammond,
36
M. Haney,
104
M. M. Hanke,
10
J. Hanks,
37
C. Hanna,
74
J. Hanson,
7
T. Hardwick,
2
J. Harms,
57,58
G. M. Harry,
3
I. W. Harry,
29
M. J. Hart,
36
M. T. Hartman,
6
C.-J. Haster,
45,97
K. Haughian,
36
J. Healy,
107
A. Heidmann,
60
M. C. Heintze,
7
H. Heitmann,
54
P. Hello,
24
G. Hemming,
34
M. Hendry,
36
I. S. Heng,
36
J. Hennig,
36
J. Henry,
107
A. W. Heptonstall,
1
M. Heurs,
10,19
S. Hild,
36
D. Hoak,
34
D. Hofman,
65
K. Holt,
7
D. E. Holz,
77
P. Hopkins,
94
J. Hough,
36
E. A. Houston,
36
E. J. Howell,
52
Y. M. Hu,
10
E. A. Huerta,
108
D. Huet,
24
B. Hughey,
103
S. Husa,
86
S. H. Huttner,
36
T. Huynh-Dinh,
7
N. Indik,
10
D. R. Ingram,
37
R. Inta,
72
H. N. Isa,
36
J.-M. Isac,
60
M. Isi,
1
T. Isogai,
12
B. R. Iyer,
17
K. Izumi,
37
T. Jacqmin,
60
K. Jani,
44
P. Jaranowski,
109
S. Jawahar,
110
F. Jim
́
enez-Forteza,
86
W. W. Johnson,
2
D. I. Jones,
111
R. Jones,
36
R. J. G. Jonker,
11
L. Ju,
52
J. Junker,
10
C. V. Kalaghatgi,
94
V. Kalogera,
85
S. Kandhasamy,
73
G. Kang,
79
J. B. Kanner,
1
S. Karki,
59
K. S. Karvinen,
10
M. Kasprzack,
2
E. Katsavounidis,
12
W. Katzman,
7
S. Kaufer,
19
T. Kaur,
52
K. Kawabe,
37
F. K
́
ef
́
elian,
54
D. Keitel,
86
D. B. Kelley,
35
R. Kennedy,
90
J. S. Key,
112
F. Y. Khalili,
49
I. Khan,
14
S. Khan,
94
Z. Khan,
89
E. A. Khazanov,
113
N. Kijbunchoo,
37
Chunglee Kim,
114
J. C. Kim,
115
arXiv:1701.07709v4 [astro-ph.HE] 4 Apr 2017
2
Whansun Kim,
116
W. Kim,
70
Y.-M. Kim,
117,114
S. J. Kimbrell,
44
E. J. King,
70
P. J. King,
37
R. Kirchhoff,
10
J. S. Kissel,
37
B. Klein,
85
L. Kleybolte,
27
S. Klimenko,
6
P. Koch,
10
S. M. Koehlenbeck,
10
S. Koley,
11
V. Kondrashov,
1
A. Kontos,
12
M. Korobko,
27
W. Z. Korth,
1
I. Kowalska,
62
D. B. Kozak,
1
C. Kr
̈
amer,
10
V. Kringel,
10
B. Krishnan,
10
A. Kr
́
olak,
118,119
G. Kuehn,
10
P. Kumar,
97
R. Kumar,
89
L. Kuo,
75
A. Kutynia,
118
B. D. Lackey,
29,35
M. Landry,
37
R. N. Lang,
18
J. Lange,
107
B. Lantz,
40
R. K. Lanza,
12
A. Lartaux-Vollard,
24
P. D. Lasky,
120
M. Laxen,
7
A. Lazzarini,
1
C. Lazzaro,
42
P. Leaci,
81,28
S. Leavey,
36
E. O. Lebigot,
30
C. H. Lee,
117
H. K. Lee,
121
H. M. Lee,
114
K. Lee,
36
J. Lehmann,
10
A. Lenon,
31
M. Leonardi,
92,93
J. R. Leong,
10
N. Leroy,
24
N. Letendre,
8
Y. Levin,
120
T. G. F. Li,
122
A. Libson,
12
T. B. Littenberg,
123
J. Liu,
52
N. A. Lockerbie,
110
A. L. Lombardi,
44
L. T. London,
94
J. E. Lord,
35
M. Lorenzini,
14,15
V. Loriette,
124
M. Lormand,
7
G. Losurdo,
21
J. D. Lough,
10,19
C. O. Lousto,
107
G. Lovelace,
23
H. L
̈
uck,
19,10
A. P. Lundgren,
10
R. Lynch,
12
Y. Ma,
51
S. Macfoy,
50
B. Machenschalk,
10
M. MacInnis,
12
D. M. Macleod,
2
F. Maga
̃
na-Sandoval,
35
E. Majorana,
28
I. Maksimovic,
124
V. Malvezzi,
26,15
N. Man,
54
V. Mandic,
125
V. Mangano,
36
G. L. Mansell,
22
M. Manske,
18
M. Mantovani,
34
F. Marchesoni,
126,33
F. Marion,
8
S. M
́
arka,
39
Z. M
́
arka,
39
A. S. Markosyan,
40
E. Maros,
1
F. Martelli,
57,58
L. Martellini,
54
I. W. Martin,
36
D. V. Martynov,
12
K. Mason,
12
A. Masserot,
8
T. J. Massinger,
1
M. Masso-Reid,
36
S. Mastrogiovanni,
81,28
F. Matichard,
12,1
L. Matone,
39
N. Mavalvala,
12
N. Mazumder,
56
R. McCarthy,
37
D. E. McClelland,
22
S. McCormick,
7
C. McGrath,
18
S. C. McGuire,
127
G. McIntyre,
1
J. McIver,
1
D. J. McManus,
22
T. McRae,
22
S. T. McWilliams,
31
D. Meacher,
54,74
G. D. Meadors,
29,10
J. Meidam,
11
A. Melatos,
128
G. Mendell,
37
D. Mendoza-Gandara,
10
R. A. Mercer,
18
E. L. Merilh,
37
M. Merzougui,
54
S. Meshkov,
1
C. Messenger,
36
C. Messick,
74
R. Metzdorff,
60
P. M. Meyers,
125
F. Mezzani,
28,81
H. Miao,
45
C. Michel,
65
H. Middleton,
45
E. E. Mikhailov,
129
L. Milano,
67,5
A. L. Miller,
6,81,28
A. Miller,
85
B. B. Miller,
85
J. Miller,
12
M. Millhouse,
84
Y. Minenkov,
15
J. Ming,
29
S. Mirshekari,
130
C. Mishra,
17
S. Mitra,
16
V. P. Mitrofanov,
49
G. Mitselmakher,
6
R. Mittleman,
12
A. Moggi,
21
M. Mohan,
34
S. R. P. Mohapatra,
12
M. Montani,
57,58
B. C. Moore,
95
C. J. Moore,
80
D. Moraru,
37
G. Moreno,
37
S. R. Morriss,
87
B. Mours,
8
C. M. Mow-Lowry,
45
G. Mueller,
6
A. W. Muir,
94
Arunava Mukherjee,
17
D. Mukherjee,
18
S. Mukherjee,
87
N. Mukund,
16
A. Mullavey,
7
J. Munch,
70
E. A. M. Muniz,
23
P. G. Murray,
36
A. Mytidis,
6
K. Napier,
44
I. Nardecchia,
26,15
L. Naticchioni,
81,28
G. Nelemans,
53,11
T. J. N. Nelson,
7
M. Neri,
46,47
M. Nery,
10
A. Neunzert,
106
J. M. Newport,
3
G. Newton,
36
T. T. Nguyen,
22
A. B. Nielsen,
10
S. Nissanke,
53,11
A. Nitz,
10
A. Noack,
10
F. Nocera,
34
D. Nolting,
7
M. E. N. Normandin,
87
L. K. Nuttall,
35
J. Oberling,
37
E. Ochsner,
18
E. Oelker,
12
G. H. Ogin,
131
J. J. Oh,
116
S. H. Oh,
116
F. Ohme,
94,10
M. Oliver,
86
P. Oppermann,
10
Richard J. Oram,
7
B. O’Reilly,
7
R. O’Shaughnessy,
107
D. J. Ottaway,
70
H. Overmier,
7
B. J. Owen,
72
A. E. Pace,
74
J. Page,
123
A. Pai,
101
S. A. Pai,
48
J. R. Palamos,
59
O. Palashov,
113
C. Palomba,
28
A. Pal-Singh,
27
H. Pan,
75
C. Pankow,
85
F. Pannarale,
94
B. C. Pant,
48
F. Paoletti,
34,21
A. Paoli,
34
M. A. Papa,
29,18,10
H. R. Paris,
40
W. Parker,
7
D. Pascucci,
36
A. Pasqualetti,
34
R. Passaquieti,
20,21
D. Passuello,
21
B. Patricelli,
20,21
B. L. Pearlstone,
36
M. Pedraza,
1
R. Pedurand,
65,132
L. Pekowsky,
35
A. Pele,
7
S. Penn,
133
C. J. Perez,
37
A. Perreca,
1
L. M. Perri,
85
H. P. Pfeiffer,
97
M. Phelps,
36
O. J. Piccinni,
81,28
M. Pichot,
54
F. Piergiovanni,
57,58
V. Pierro,
9
G. Pillant,
34
L. Pinard,
65
I. M. Pinto,
9
M. Pitkin,
36
M. Poe,
18
R. Poggiani,
20,21
P. Popolizio,
34
A. Post,
10
J. Powell,
36
J. Prasad,
16
J. W. W. Pratt,
103
V. Predoi,
94
T. Prestegard,
125,18
M. Prijatelj,
10,34
M. Principe,
9
S. Privitera,
29
R. Prix,
10
G. A. Prodi,
92,93
L. G. Prokhorov,
49
O. Puncken,
10
M. Punturo,
33
P. Puppo,
28
M. P
̈
urrer,
29
H. Qi,
18
J. Qin,
52
S. Qiu,
120
V. Quetschke,
87
E. A. Quintero,
1
R. Quitzow-James,
59
F. J. Raab,
37
D. S. Rabeling,
22
H. Radkins,
37
P. Raffai,
98
S. Raja,
48
C. Rajan,
48
M. Rakhmanov,
87
P. Rapagnani,
81,28
V. Raymond,
29
M. Razzano,
20,21
V. Re,
26
J. Read,
23
T. Regimbau,
54
L. Rei,
47
S. Reid,
50
D. H. Reitze,
1,6
H. Rew,
129
S. D. Reyes,
35
E. Rhoades,
103
F. Ricci,
81,28
K. Riles,
106
M. Rizzo,
107
N. A. Robertson,
1,36
R. Robie,
36
F. Robinet,
24
A. Rocchi,
15
L. Rolland,
8
J. G. Rollins,
1
V. J. Roma,
59
R. Romano,
4,5
J. H. Romie,
7
D. Rosi
́
nska,
134,43
S. Rowan,
36
A. R
̈
udiger,
10
P. Ruggi,
34
K. Ryan,
37
S. Sachdev,
1
T. Sadecki,
37
L. Sadeghian,
18
M. Sakellariadou,
135
L. Salconi,
34
M. Saleem,
101
F. Salemi,
10
A. Samajdar,
136
L. Sammut,
120
L. M. Sampson,
85
E. J. Sanchez,
1
V. Sandberg,
37
J. R. Sanders,
35
B. Sassolas,
65
B. S. Sathyaprakash,
74,94
P. R. Saulson,
35
O. Sauter,
106
R. L. Savage,
37
A. Sawadsky,
19
P. Schale,
59
J. Scheuer,
85
E. Schmidt,
103
J. Schmidt,
10
P. Schmidt,
1,51
R. Schnabel,
27
R. M. S. Schofield,
59
A. Sch
̈
onbeck,
27
E. Schreiber,
10
D. Schuette,
10,19
B. F. Schutz,
94,29
S. G. Schwalbe,
103
J. Scott,
36
S. M. Scott,
22
D. Sellers,
7
A. S. Sengupta,
137
D. Sentenac,
34
V. Sequino,
26,15
A. Sergeev,
113
Y. Setyawati,
53,11
D. A. Shaddock,
22
T. J. Shaffer,
37
M. S. Shahriar,
85
B. Shapiro,
40
P. Shawhan,
64
A. Sheperd,
18
D. H. Shoemaker,
12
D. M. Shoemaker,
44
K. Siellez,
44
X. Siemens,
18
M. Sieniawska,
43
D. Sigg,
37
A. D. Silva,
13
A. Singer,
1
L. P. Singer,
68
A. Singh,
29,10,19
R. Singh,
2
A. Singhal,
14
A. M. Sintes,
86
B. J. J. Slagmolen,
22
B. Smith,
7
J. R. Smith,
23
R. J. E. Smith,
1
E. J. Son,
116
B. Sorazu,
36
F. Sorrentino,
47
T. Souradeep,
16
A. P. Spencer,
36
A. K. Srivastava,
89
A. Staley,
39
M. Steinke,
10
J. Steinlechner,
36
S. Steinlechner,
27,36
D. Steinmeyer,
10,19
B. C. Stephens,
18
S. P. Stevenson,
45
R. Stone,
87
K. A. Strain,
36
N. Straniero,
65
G. Stratta,
57,58
S. E. Strigin,
49
R. Sturani,
130
A. L. Stuver,
7
T. Z. Summerscales,
138
L. Sun,
128
S. Sunil,
89
P. J. Sutton,
94
B. L. Swinkels,
34
M. J. Szczepa
́
nczyk,
103
M. Tacca,
30
D. Talukder,
59
D. B. Tanner,
6
M. T
́
apai,
102
A. Taracchini,
29
R. Taylor,
1
T. Theeg,
10
E. G. Thomas,
45
M. Thomas,
7
P. Thomas,
37
K. A. Thorne,
7
E. Thrane,
120
T. Tippens,
44
S. Tiwari,
14,93
V. Tiwari,
94
K. V. Tokmakov,
110
K. Toland,
36
C. Tomlinson,
90
M. Tonelli,
20,21
Z. Tornasi,
36
C. I. Torrie,
1
D. T
̈
oyr
̈
a,
45
F. Travasso,
32,33
G. Traylor,
7
D. Trifir
`
o,
73
J. Trinastic,
6
M. C. Tringali,
92,93
L. Trozzo,
139,21
M. Tse,
12
R. Tso,
1
M. Turconi,
54
D. Tuyenbayev,
87
D. Ugolini,
140
C. S. Unnikrishnan,
104
A. L. Urban,
1
S. A. Usman,
94
H. Vahlbruch,
19
G. Vajente,
1
G. Valdes,
87
N. van Bakel,
11
M. van Beuzekom,
11
J. F. J. van den Brand,
63,11
C. Van Den Broeck,
11
D. C. Vander-Hyde,
35
L. van der Schaaf,
11
J. V. van Heijningen,
11
A. A. van Veggel,
36
M. Vardaro,
41,42
V. Varma,
51
S. Vass,
1
M. Vas
́
uth,
38
A. Vecchio,
45
G. Vedovato,
42
J. Veitch,
45
P. J. Veitch,
70
K. Venkateswara,
141
G. Venugopalan,
1
D. Verkindt,
8
F. Vetrano,
57,58
A. Vicer
́
e,
57,58
A. D. Viets,
18
S. Vinciguerra,
45
D. J. Vine,
50
J.-Y. Vinet,
54
S. Vitale,
12
T. Vo,
35
H. Vocca,
32,33
C. Vorvick,
37
D. V. Voss,
6
W. D. Vousden,
45
S. P. Vyatchanin,
49
A. R. Wade,
1
L. E. Wade,
78
M. Wade,
78
M. Walker,
2
L. Wallace,
1
S. Walsh,
29,10
G. Wang,
14,58
H. Wang,
45
M. Wang,
45
Y. Wang,
52
R. L. Ward,
22
J. Warner,
37
M. Was,
8
J. Watchi,
82
B. Weaver,
37
L.-W. Wei,
54
M. Weinert,
10
A. J. Weinstein,
1
R. Weiss,
12
Gravitational waves from known pulsars
3
L. Wen,
52
P. Weßels,
10
T. Westphal,
10
K. Wette,
10
J. T. Whelan,
107
B. F. Whiting,
6
C. Whittle,
120
D. Williams,
36
R. D. Williams,
1
A. R. Williamson,
94
J. L. Willis,
142
B. Willke,
19,10
M. H. Wimmer,
10,19
W. Winkler,
10
C. C. Wipf,
1
H. Wittel,
10,19
G. Woan,
36
J. Woehler,
10
J. Worden,
37
J. L. Wright,
36
D. S. Wu,
10
G. Wu,
7
W. Yam,
12
H. Yamamoto,
1
C. C. Yancey,
64
M. J. Yap,
22
Hang Yu,
12
Haocun Yu,
12
M. Yvert,
8
A. Zadro
̇
zny,
118
L. Zangrando,
42
M. Zanolin,
103
J.-P. Zendri,
42
M. Zevin,
85
L. Zhang,
1
M. Zhang,
129
T. Zhang,
36
Y. Zhang,
107
C. Zhao,
52
M. Zhou,
85
Z. Zhou,
85
S. J. Zhu,
29,10
X. J. Zhu,
52
M. E. Zucker,
1,12
and J. Zweizig
1
Deceased, March 2016.
(LIGO Scientific Collaboration and Virgo Collaboration)
S. Buchner
143,144
, I. Cognard
145,146
, A. Corongiu
147
, P. C. C. Freire
148
, L. Guillemot
145,146
, G. B. Hobbs
149
,
M. Kerr
149
, A. G. Lyne
150
, A. Possenti
147
, A. Ridolfi
148
, R. M. Shannon
151,152
, B. W. Stappers
150
, and
P. Weltevrede
150
Draft version April 5, 2017
ABSTRACT
We present the result of searches for gravitational waves from 200 pulsars using data from the first
observing run of the Advanced LIGO detectors. We find no significant evidence for a gravitational-
wave signal from any of these pulsars, but we are able to set the most constraining upper limits yet
on their gravitational-wave amplitudes and ellipticities. For eight of these pulsars, our upper limits
give bounds that are improvements over the indirect spin-down limit values. For another 32, we are
within a factor of 10 of the spin-down limit, and it is likely that some of these will be reachable in
future runs of the advanced detector. Taken as a whole, these new results improve on previous limits
by more than a factor of two.
Keywords:
gravitational waves - pulsars: general
1
LIGO, California Institute of Technology, Pasadena, CA
91125, USA
2
Louisiana State University, Baton Rouge, LA 70803, USA
3
American University, Washington, D.C. 20016, USA
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
University of Florida, Gainesville, FL 32611, USA
7
LIGO Livingston Observatory, Livingston, LA 70754, USA
8
Laboratoire d’Annecy-le-Vieux de Physique des Particules
(LAPP), Universit ́e 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 f ̈ur Gravita-
tionsphysik, D-30167 Hannover, Germany
11
Nikhef, Science Park, 1098 XG Amsterdam, The Netherlands
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
INFN, Gran Sasso Science Institute, I-67100 L’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, Bengaluru 560089, India
18
University of Wisconsin-Milwaukee, Milwaukee, WI 53201,
USA
19
Leibniz Universit ̈at Hannover, D-30167 Hannover, Germany
20
Universit`a 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
California State University Fullerton, Fullerton, CA 92831,
USA
24
LAL, Univ.
Paris-Sud, CNRS/IN2P3, Universit ́e Paris-
Saclay, F-91898 Orsay, France
25
Chennai Mathematical Institute, Chennai 603103, India
26
Universit`a di Roma Tor Vergata, I-00133 Roma, Italy
27
Universit ̈at Hamburg, D-22761 Hamburg, Germany
28
INFN, Sezione di Roma, I-00185 Roma, Italy
29
Albert-Einstein-Institut,
Max-Planck-Institut
f ̈ur
Gravitationsphysik, D-14476 Potsdam-Golm, Germany
30
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
31
West Virginia University, Morgantown, WV 26506, USA
32
Universit`a di Perugia, I-06123 Perugia, Italy
33
INFN, Sezione di Perugia, I-06123 Perugia, Italy
34
European Gravitational Observatory (EGO), I-56021 Cascina,
Pisa, Italy
35
Syracuse University, Syracuse, NY 13244, USA
36
SUPA, University of Glasgow, Glasgow G12 8QQ, UK
37
LIGO Hanford Observatory, Richland, WA 99352, USA
38
Wigner RCP, RMKI, H-1121 Budapest, Konkoly Thege
Mikl ́os ́ut 29-33, Hungary
39
Columbia University, New York, NY 10027, USA
40
Stanford University, Stanford, CA 94305, USA
41
Universit`a di Padova, Dipartimento di Fisica e Astronomia,
I-35131 Padova, Italy
42
INFN, Sezione di Padova, I-35131 Padova, Italy
43
Nicolaus Copernicus Astronomical Center, Polish Academy
of Sciences, 00-716, Warsaw, Poland
44
Center for Relativistic Astrophysics and School of Physics,
Georgia Institute of Technology, Atlanta, GA 30332, USA
45
University of Birmingham, Birmingham B15 2TT, UK
46
Universit`a degli Studi di Genova, I-16146 Genova, Italy
47
INFN, Sezione di Genova, I-16146 Genova, Italy
48
RRCAT, Indore MP 452013, India
49
Faculty of Physics, Lomonosov Moscow State University,
Moscow 119991, Russia
50
SUPA, University of the West of Scotland, Paisley PA1 2BE,
UK
51
Caltech CaRT, Pasadena, CA 91125, USA
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, Universit ́e Cˆote d’Azur, CNRS, Observatoire Cˆote
d’Azur, CS 34229, F-06304 Nice Cedex 4, France
55
Institut de Physique de Rennes, CNRS, Universit ́e de Rennes
1, F-35042 Rennes, France
56
Washington State University, Pullman, WA 99164, USA
57
Universit`a 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, OR 97403, USA
60
Laboratoire Kastler Brossel, UPMC-Sorbonne Universit ́es,
CNRS, ENS-PSL Research University, Coll`ege de France, F-75005
Paris, France
4
1.
INTRODUCTION
The recent observations of gravitational waves from
the inspiral and merger of binary black holes herald
the era of gravitational-wave astronomy (Abbott et al.
2016c,b). Such cataclysmic, transient, and extragalatic
events are not however the only potential sources of ob-
servable gravitational waves. Galactic neutron stars of-
61
Carleton College, Northfield, MN 55057, USA
62
Astronomical Observatory Warsaw University, 00-478 War-
saw, Poland
63
VU University Amsterdam, 1081 HV Amsterdam, The
Netherlands
64
University of Maryland, College Park, MD 20742, USA
65
Laboratoire des Mat ́eriaux Avanc ́es (LMA), CNRS/IN2P3,
F-69622 Villeurbanne, France
66
Universit ́e Claude Bernard Lyon 1, F-69622 Villeurbanne,
France
67
Universit`a di Napoli ’Federico II’, Complesso Universitario di
Monte S.Angelo, I-80126 Napoli, Italy
68
NASA/Goddard Space Flight Center, Greenbelt, MD 20771,
USA
69
RESCEU, University of Tokyo, Tokyo, 113-0033, Japan.
70
University of Adelaide, Adelaide, South Australia 5005,
Australia
71
Tsinghua University, Beijing 100084, China
72
Texas Tech University, Lubbock, TX 79409, USA
73
The University of Mississippi, University, MS 38677, USA
74
The Pennsylvania State University, University Park, PA
16802, USA
75
National Tsing Hua University, Hsinchu City, 30013 Taiwan,
Republic of China
76
Charles Sturt University, Wagga Wagga, New South Wales
2678, Australia
77
University of Chicago, Chicago, IL 60637, USA
78
Kenyon College, Gambier, OH 43022, USA
79
Korea Institute of Science and Technology Information,
Daejeon 305-806, Korea
80
University of Cambridge, Cambridge CB2 1TN, UK
81
Universit`a di Roma ’La Sapienza’, I-00185 Roma, Italy
82
University of Brussels, Brussels 1050, Belgium
83
Sonoma State University, Rohnert Park, CA 94928, USA
84
Montana State University, Bozeman, MT 59717, USA
85
Center for Interdisciplinary Exploration & Research in
Astrophysics (CIERA), Northwestern University, Evanston, IL
60208, USA
86
Universitat de les Illes Balears, IAC3—IEEC, E-07122 Palma
de Mallorca, Spain
87
The University of Texas Rio Grande Valley, Brownsville, TX
78520, USA
88
Bellevue College, Bellevue, WA 98007, USA
89
Institute for Plasma Research, Bhat, Gandhinagar 382428,
India
90
The University of Sheffield, Sheffield S10 2TN, UK
91
California State University, Los Angeles, 5154 State Univer-
sity Dr, Los Angeles, CA 90032, USA
92
Universit`a di Trento, Dipartimento di Fisica, I-38123 Povo,
Trento, Italy
93
INFN, Trento Institute for Fundamental Physics and Appli-
cations, I-38123 Povo, Trento, Italy
94
Cardiff University, Cardiff CF24 3AA, UK
95
Montclair State University, Montclair, NJ 07043, USA
96
National Astronomical Observatory of Japan, 2-21-1 Osawa,
Mitaka, Tokyo 181-8588, Japan
97
Canadian Institute for Theoretical Astrophysics, University
of Toronto, Toronto, Ontario M5S 3H8, Canada
98
MTA E ̈otv ̈os University, “Lendulet” Astrophysics Research
Group, Budapest 1117, Hungary
99
School of Mathematics, University of Edinburgh, Edinburgh
EH9 3FD, UK
100
University and Institute of Advanced Research, Gandhina-
gar, Gujarat 382007, India
101
IISER-TVM, CET Campus, Trivandrum Kerala 695016,
India
102
University of Szeged, D ́om t ́er 9, Szeged 6720, Hungary
103
Embry-Riddle Aeronautical University, Prescott, AZ 86301,
fer a more local, and continuous, quasi-monochromatic
source of gravitational radiation. Although intrinsically
far weaker than the transient sources that have been ob-
served, their continuous nature allows their signals to be
found buried deep in the noise by coherently integrating
over the long observing runs of the gravitational-wave
observatories.
The subset of known pulsars, identified through elec-
USA
104
Tata Institute of Fundamental Research, Mumbai 400005,
India
105
INAF, Osservatorio Astronomico di Capodimonte, I-80131,
Napoli, Italy
106
University of Michigan, Ann Arbor, MI 48109, USA
107
Rochester Institute of Technology, Rochester, NY 14623,
USA
108
NCSA, University of Illinois at Urbana-Champaign, Urbana,
IL 61801, USA
109
University of Bia lystok, 15-424 Bia lystok, Poland
110
SUPA, University of Strathclyde, Glasgow G1 1XQ, UK
111
University of Southampton, Southampton SO17 1BJ, UK
112
University of Washington Bothell, 18115 Campus Way NE,
Bothell, WA 98011, USA
113
Institute of Applied Physics, Nizhny Novgorod, 603950,
Russia
114
Seoul National University, Seoul 151-742, Korea
115
Inje University Gimhae, 621-749 South Gyeongsang, Korea
116
National Institute for Mathematical Sciences, Daejeon
305-390, Korea
117
Pusan National University, Busan 609-735, Korea
118
NCBJ, 05-400
́
Swierk-Otwock, Poland
119
Institute of Mathematics, Polish Academy of Sciences, 00656
Warsaw, Poland
120
Monash University, Victoria 3800, Australia
121
Hanyang University, Seoul 133-791, Korea
122
The Chinese University of Hong Kong, Shatin, NT, Hong
Kong
123
University of Alabama in Huntsville, Huntsville, AL 35899,
USA
124
ESPCI, CNRS, F-75005 Paris, France
125
University of Minnesota, Minneapolis, MN 55455, USA
126
Universit`a di Camerino, Dipartimento di Fisica, I-62032
Camerino, Italy
127
Southern University and A&M College, Baton Rouge, LA
70813, USA
128
The University of Melbourne, Parkville, Victoria 3010,
Australia
129
College of William and Mary, Williamsburg, VA 23187, USA
130
Instituto
de
F ́ısica
Te ́orica,
University
Estadual
Paulista/ICTP South American Institute for Fundamental
Research, S ̃ao Paulo SP 01140-070, Brazil
131
Whitman College, 345 Boyer Avenue, Walla Walla, WA
99362 USA
132
Universit ́e de Lyon, F-69361 Lyon, France
133
Hobart and William Smith Colleges, Geneva, NY 14456,
USA
134
Janusz Gil Institute of Astronomy, University of Zielona
G ́ora, 65-265 Zielona G ́ora, Poland
135
King’s College London, University of London, London
WC2R 2LS, UK
136
IISER-Kolkata, Mohanpur, West Bengal 741252, India
137
Indian Institute of Technology, Gandhinagar Ahmedabad
Gujarat 382424, India
138
Andrews University, Berrien Springs, MI 49104, USA
139
Universit`a di Siena, I-53100 Siena, Italy
140
Trinity University, San Antonio, TX 78212, USA
141
University of Washington, Seattle, WA 98195, USA
142
Abilene Christian University, Abilene, TX 79699, USA
143
Square Kilometer Array South Africa, The Park, Park Road,
Pinelands, Cape Town 7405, South Africa
144
Hartebeesthoek Radio Astronomy Observatory, PO Box
443, Krugersdorp, 1740, South Africa
145
Laboratoire de Physique et Chimie de l’Environnement et de
l’Espace, LPC2E, CNRS-Universit ́e d’Orl ́eans, F-45071 Orl ́eans,
France
146
Station de Radioastronomie de Nan ̧cay, Observatoire de
Gravitational waves from known pulsars
5
tromagnetic observations, provides an important possi-
ble source of continuous gravitational waves. They are
often timed with exquisite precision, allowing their ro-
tational phase evolution, sky location and, if required,
binary orbital parameters to be determined very accu-
rately. In turn, these timings allow us to carry out fully
phase-coherent and computationally cheap gravitational-
wave searches over the length of our observation runs. A
selection of known pulsars have already been targeted us-
ing data from the initial LIGO, Virgo, and GEO 600 de-
tectors (summarized in Aasi et al. 2014), setting upper
limits on their signal amplitudes, though without any
detections.
An important milestone is passed when this upper
limit falls below the so-called spin-down limit on grav-
itational strain for the targeted pulsar.
This spin-
down limit is determined by equating the power radi-
ated through gravitational-wave emission to the pulsar’s
observed spin-down luminosity (attributed to its loss in
rotational kinetic energy), i.e. as would be the case if it
were a
gravitar
(Palomba 2005; Knispel & Allen 2008),
and determining the equivalent strain expected at the
Earth.
153
It can be calculated (see, e.g. Aasi et al. 2014)
using
h
sd
0
=
(
5
2
GI
zz
|
̇
f
rot
|
c
3
d
2
f
rot
)
1
/
2
,
(1)
where
f
rot
and
̇
f
rot
are the pulsar’s frequency and first
frequency derivative,
I
zz
is the principal moment of in-
ertia (for which we generally assume a canonical value of
10
38
kg m
2
), and
d
is the pulsar’s distance. In previous
searches, this limit has been surpassed (i.e. a smaller limit
on the strain amplitude has been obtained) for two pul-
sars: PSR J0534+2200 (the Crab pulsar; Abbott et al.
2008) and PSR J0835
4510 (the Vela pulsar; Abadie
et al. 2011).
In this paper, we provide results from a search for
gravitational waves from 200 known pulsars using data
from the first observing run (O1) of Advanced LIGO
(aLIGO). For the LIGO Hanford Observatory (H1) and
LIGO Livingston Observatory (L1), we used data start-
ing on 2015 September 11 at 01:25:03 UTC and 18:29:03
UTC, respectively, and finishing on 2016 January 19 at
17:07:59 UTC at both sites. With duty factors of 60%
Paris, CNRS/INSU, F-18330 Nan ̧cay, France
147
INAF - Osservatorio Astronomico di Cagliari, via della
Scienza 5, 09047 Selargius, Italy
148
Max-Planck-Institut f ̈ur Radioastronomie MPIfR, Auf dem
H ̈ugel 69, D-53121 Bonn, Germany
149
CSIRO Astronomy and Space Science, Australia Telescope
National Facility, Box 76 Epping, NSW, 1710, Australia
150
Jodrell Bank Centre for Astrophysics, School of Physics and
Astronomy, University of Manchester, Manchester M13 9PL, UK
151
CSIRO Astronomy and Space Science, Australia Telescope
National Facility, Box 76 Epping, NSW, 1710, Australia
152
International Centre for Radio Astronomy Research, Curtin
University, Bentley, WA 6102, Australia
153
This is known to be a na ̈ıve limit. For several young pul-
sars where the braking index (see Section 4) is measured (Lyne
et al. 2015; Archibald et al. 2016), we know that it is not consis-
tent with pure gravitational wave emission, and other energy-loss
mechanisms can be dominant. Effects of this on spin-down limit
calculations are discussed in Palomba (2000). Figures 9 and 10 of
Abdo et al. (2013) also show that for pulsars observed as
Fermi
gamma-ray sources, a not insignificant proportion of their spin-
down luminosity is emitted through gamma-rays.
and 51% for H1 and L1, this run provided 78 days and
66 days of data respectively for analysis. The estimated
sensitivity of this search as a function of source frequency
is shown in Figure 1.
154
We see that, even with its com-
paratively short observation time, the O1 data provide
a significant sensitivity improvement over the previous
runs, particularly at lower frequencies.
1.1.
The signal
We model the source as a rigidly rotating triaxial star,
generating a strain signal at the detector of (e.g. Jara-
nowski et al. 1998)
h
(
t
) =
h
0
[
1
2
F
D
+
(
t,α,δ,ψ
)(1 + cos
2
ι
) cos
φ
(
t
)
+
F
D
×
(
t,α,δ,ψ
) cos
ι
sin
φ
(
t
)
]
(2)
where
h
0
is the gravitational-wave strain amplitude, and
F
D
+
and
F
D
×
are the antenna responses of observatory
D
to the ‘+’ and ‘
×
’ polarizations. These are dependent on
the source sky position (right ascension
α
and declination
δ
) and polarization angle
ψ
.
ι
is the inclination of the
star’s rotation axis to the line of sight, and
φ
(
t
) represents
the evolution of the sinusoidal signal phase with time.
This phase evolution is usefully represented as a Taylor
expansion, so that
φ
(
t
) =
φ
0
+ 2
π
N
j
=0
(j)
f
0
(
j
+ 1)!
(
t
T
0
+
δt
(
t
))
(
j
+1)
,
(3)
where
φ
0
is the initial gravitational-wave phase at time
epoch
T
0
, and
(j)
f
0
is the
j
th
time derivative of the
gravitational-wave frequency defined at
T
0
.
δt
(
t
) is the
time delay from the observatory to the solar system
barycenter, and can also include binary system barycen-
tering corrections to put the observatory and source in
inertial frames. For the majority of pulsars, expansions
to
N
= 1 or 2 are all that are required, but for some
young sources, with significant timing noise, expansions
to higher orders may be used. For the case of a source
rotating around a principal axis of inertia and producing
emission from the
l
=
m
= 2 (spherical harmonic) mass
quadrupole mode (e.g. a rigidly rotating star with a tri-
axial moment of inertia ellipsoid), the gravitational-wave
frequencies and frequency derivatives are all twice their
rotational values, e.g.
f
= 2
f
rot
.
2.
PULSAR SELECTION
To reflect the improved sensitivity of LIGO during O1,
we targeted pulsars with rotation frequencies,
f
rot
, of
greater than about 10 Hz, but also included seven promis-
ing sources with large spin-down luminosities
155
with
f
rot
154
The sensitivity is taken as 10
.
8
S
n
, where
S
n
is
the harmonic mean of the observation-time-weighted one-sided
power spectral densities,
S
n
/T
, for H1 and L1 (see
https:
//dcc.ligo.org/LIGO-G1600150/public
and
https://dcc.ligo.
org/LIGO-G1600151/public
, respectively). The factor of 10.8 gives
the 95% credible upper limit on gravitational-wave strain ampli-
tude averaged over orientation angles assuming Gaussian noise
(Dupuis & Woan 2005).
155
PSRs J0908
4913, J1418
6058, J1709
4429, J1826
1334,
J1845
0743, J1853
0004, and J2129+1210A
6
10
2
10
3
Gravitational-wave Frequency (Hz)
10
27
10
26
10
25
10
24
10
23
Strain Sensitivity
h
0
O1 sensitivity estimate
O1 results
spin-down limits
surpass spin-down limits
Initial detector results
Figure 1.
Stars show 95% credible upper limits on gravitational-wave amplitude,
h
95%
0
, for 200 pulsars using data from the O1 run.
H
give the spin-down limits for all pulsars (based on distance values taken from the ATNF pulsar catalog (Manchester et al. 2005), unless
otherwise stated in Tables 1 and 4) and assuming the canonical moment of inertia. The upper limits shown within the shaded circles are
those for which the spin-down limits (linked via the dashed vertical lines) are surpassed with our observations. The gray curve gives an
estimate of the expected strain sensitivity for O1, combining representative amplitude spectral density measurements for both H1 and L1.
This estimate is an angle-averaged value and for particular sources is representative only, whilst the broader range over all angles for such
an estimate is shown, for example, in Figure 4 of Abbott et al. (2010a). Previous initial detector run results (Aasi et al. 2014) for 195
pulsars are shown as red circles, with 122 of these sources corresponding to sources searched for in O1.