@article{0a2b1082f98b41fc9b246e60dedb917c,

title = "Directional limits on persistent gravitational waves using data from Advanced LIGO's first two observing runs",

abstract = "We perform an unmodeled search for persistent, directional gravitational wave (GW) sources using data from the first and second observing runs of Advanced LIGO. We do not find evidence for any GW signals. We place limits on the broadband GW flux emitted at 25 Hz from point sources with a power law spectrum at Fα,Θ<(0.05-25)×10-8 erg cm-2 s-1 Hz-1 and the (normalized) energy density spectrum in GWs at 25 Hz from extended sources at ωα(Θ)<(0.19-2.89)×10-8 sr-1 where α is the spectral index of the energy density spectrum. These represent improvements of 2.5-3× over previous limits. We also consider point sources emitting GWs at a single frequency, targeting the directions of Sco X-1, SN 1987A, and the Galactic center. The best upper limits on the strain amplitude of a potential source in these three directions range from h0<(3.6-4.7)×10-25, 1.5× better than previous limits set with the same analysis method. We also report on a marginally significant outlier at 36.06 Hz. This outlier is not consistent with a persistent gravitational-wave source as its significance diminishes when combining all of the available data.",

author = "{LIGO Scientific Collaboration and Virgo Collaborations} and Abbott, {B. P.} and R. Abbott and Abbott, {T. D.} and S. Abraham and F. Acernese and K. Ackley and C. Adams and Adhikari, {R. X.} and Adya, {V. B.} and C. Affeldt and M. Agathos and K. Agatsuma and N. Aggarwal and Aguiar, {O. D.} and L. Aiello and A. Ain and P. Ajith and G. Allen and A. Allocca and Aloy, {M. A.} and Altin, {P. A.} and A. Amato and A. Ananyeva and Anderson, {S. B.} and Anderson, {W. G.} and Angelova, {S. V.} and S. Antier and S. Appert and K. Arai and Araya, {M. C.} and Areeda, {J. S.} and M. Ar{\`e}ne and N. Arnaud and S. Ascenzi and G. Ashton and Aston, {S. M.} and P. Astone and F. Aubin and P. Aufmuth and K. Aultoneal and C. Austin and V. Avendano and A. Avila-Alvarez and S. Babak and P. Bacon and F. Badaracco and Bader, {M. K.M.} and S. Bae and Baker, {P. T.} and F. Baldaccini and G. Ballardin and Ballmer, {S. W.} and S. Banagiri and Barayoga, {J. C.} and Barclay, {S. E.} and Barish, {B. C.} and D. Barker and K. Barkett and S. Barnum and F. Barone and B. Barr and L. Barsotti and M. Barsuglia and D. Barta and J. Bartlett and I. Bartos and R. Bassiri and A. Basti and M. Bawaj and Bayley, {J. C.} and M. Bazzan and B. B{\'e}csy and M. Bejger and I. Belahcene and Bell, {A. S.} and D. Beniwal and Berger, {B. K.} and G. Bergmann and S. Bernuzzi and Bero, {J. J.} and Berry, {C. P.L.} and D. Bersanetti and A. Bertolini and J. Betzwieser and R. Bhandare and J. Bidler and Bilenko, {I. A.} and Bilgili, {S. A.} and G. Billingsley and J. Birch and R. Birney and O. Birnholtz and S. Biscans and S. Biscoveanu and A. Bisht and M. Bitossi and Bizouard, {M. A.} and Blackburn, {J. K.} and Blair, {C. D.} and Blair, {D. G.} and Blair, {R. M.} and S. Bloemen and N. Bode and M. Boer and Y. Boetzel and G. Bogaert and F. Bondu and E. Bonilla and R. Bonnand and P. Booker and Boom, {B. A.} and Booth, {C. D.} and R. Bork and V. Boschi and S. Bose and K. Bossie and V. Bossilkov and J. Bosveld and Y. Bouffanais and A. Bozzi and C. Bradaschia and Brady, {P. R.} and A. Bramley and M. Branchesi and Brau, {J. E.} and T. Briant and Briggs, {J. H.} and F. Brighenti and A. Brillet and M. Brinkmann and V. Brisson and P. Brockill and Brooks, {A. F.} and Brown, {D. D.} and S. Brunett and A. Buikema and T. Bulik and Bulten, {H. J.} and A. Buonanno and D. Buskulic and C. Buy and Byer, {R. L.} and M. Cabero and L. Cadonati and G. Cagnoli and C. Cahillane and Bustillo, {J. Calder{\'o}n} and Callister, {T. A.} and E. Calloni and Camp, {J. B.} and Campbell, {W. A.} and M. Canepa and Cannon, {K. C.} and H. Cao and J. Cao and E. Capocasa and F. Carbognani and S. Caride and Carney, {M. F.} and G. Carullo and Diaz, {J. Casanueva} and C. Casentini and S. Caudill and M. Cavagli{\`a} and F. Cavalier and R. Cavalieri and G. Cella and P. Cerd{\'a}-Dur{\'a}n and G. Cerretani and E. Cesarini and O. Chaibi and K. Chakravarti and Chamberlin, {S. J.} and M. Chan and S. Chao and P. Charlton and Chase, {E. A.} and E. Chassande-Mottin and D. Chatterjee and M. Chaturvedi and Cheeseboro, {B. D.} and Chen, {H. Y.} and X. Chen and Y. Chen and Cheng, {H. P.} and Cheong, {C. K.} and Chia, {H. Y.} and A. Chincarini and A. Chiummo and G. Cho and Cho, {H. S.} and M. Cho and N. Christensen and Q. Chu and S. Chua and Chung, {K. W.} and S. Chung and G. Ciani and Ciobanu, {A. A.} and R. Ciolfi and F. Cipriano and A. Cirone and F. Clara and Clark, {J. A.} and P. Clearwater and F. Cleva and C. Cocchieri and E. Coccia and Cohadon, {P. F.} and D. Cohen and R. Colgan and M. Colleoni and Collette, {C. G.} and C. Collins and Cominsky, {L. R.} and M. Constancio and L. Conti and Cooper, {S. J.} and P. Corban and Corbitt, {T. R.} and I. Cordero-Carri{\'o}n and Corley, {K. R.} and N. Cornish and A. Corsi and S. Cortese and Costa, {C. A.} and R. Cotesta and Coughlin, {M. W.} and Coughlin, {S. B.} and Coulon, {J. P.} and Countryman, {S. T.} and P. Couvares and Covas, {P. B.} and Cowan, {E. E.} and Coward, {D. M.} and Cowart, {M. J.} and Coyne, {D. C.} and R. Coyne and Creighton, {J. D.E.} and Danilishin, {S. L.} and J. Degallaix and Howell, {E. J.} and L. Ju and J. Liu and McCann, {J. J.} and Page, {M. A.} and Slaven-Blair, {T. J.} and {Van Heijningen}, {J. V.} and L. Wen and Zhu, {X. J.}",

year = "2019",

month = sep,

day = "4",

doi = "10.1103/PhysRevD.100.062001",

language = "English",

volume = "100",

journal = "Physical Review D",

issn = "2470-0010",

publisher = "American Physical Society",

number = "6",

}