@article{6a4acd0663304b539f3ca7a07994a1d0,

title = "GWTC-2: Compact binary coalescences observed by LIGO and Virgo during the first half of the third observing run",

abstract = "We report on gravitational-wave discoveries from compact binary coalescences detected by Advanced LIGO and Advanced Virgo in the first half of the third observing run (O3a) between 1 April 2019 15∶00 UTC and 1 October 2019 15∶00 UTC. By imposing a false-alarm-rate threshold of two per year in each of the four search pipelines that constitute our search, we present 39 candidate gravitational-wave events. At this threshold, we expect a contamination fraction of less than 10%. Of these, 26 candidate events were reported previously in near-real time through gamma-ray coordinates network notices and circulars; 13 are reported here for the first time. The catalog contains events whose sources are black hole binary mergers up to a redshift of approximately 0.8, as well as events whose components cannot be unambiguously identified as black holes or neutron stars. For the latter group, we are unable to determine the nature based on estimates of the component masses and spins from gravitational-wave data alone. The range of candidate event masses which are unambiguously identified as binary black holes (both objects ≥3 M⊙) is increased compared to GWTC-1, with total masses from approximately 14 M⊙ for GW190924_021846 to approximately 150 M⊙ for GW190521. For the first time, this catalog includes binary systems with significantly asymmetric mass ratios, which had not been observed in data taken before April 2019. We also find that 11 of the 39 events detected since April 2019 have positive effective inspiral spins under our default prior (at 90% credibility), while none exhibit negative effective inspiral spin. Given the increased sensitivity of Advanced LIGO and Advanced Virgo, the detection of 39 candidate events in approximately 26 weeks of data (approximately 1.5 per week) is consistent with GWTC-1.",

author = "{LIGO Scientific Collaboration and Virgo Collaboration} and R. Abbott and Abbott, {T. D.} and S. Abraham and F. Acernese and K. Ackley and A. Adams 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 S. Akcay and G. Allen and A. Allocca and Altin, {P. A.} and A. Amato and S. Anand and A. Ananyeva and Anderson, {S. B.} and Anderson, {W. G.} and Angelova, {S. V.} and S. Ansoldi and Antelis, {J. M.} 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 Aronson, {S. M.} and Arun, {K. G.} and Y. Asali 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 S. Babak and F. Badaracco and Bader, {M. K.M.} and S. Bae and Baer, {A. M.} and S. Bagnasco and J. Baird and M. Ball and G. Ballardin and Ballmer, {S. W.} and A. Bals and A. Balsamo and G. Baltus and S. Banagiri and D. Bankar and Bankar, {R. S.} and Barayoga, {J. C.} and C. Barbieri and Barish, {B. C.} and D. Barker and P. Barneo 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 Becher, {B. R.} and B. B{\'e}csy and Bedakihale, {V. M.} and M. Bejger and I. Belahcene and D. Beniwal and Benjamin, {M. G.} and Bennett, {T. F.} and Bentley, {J. D.} and F. Bergamin and Berger, {B. K.} and G. Bergmann and S. Bernuzzi and Berry, {C. P.L.} and D. Bersanetti and A. Bertolini and J. Betzwieser and R. Bhandare and Bhandari, {A. V.} and D. Bhattacharjee and J. Bidler and Bilenko, {I. A.} and G. Billingsley and R. Birney and O. Birnholtz and S. Biscans and M. Bischi and S. Biscoveanu and A. Bisht and M. Bitossi and Bizouard, {M. A.} and Blackburn, {J. K.} and J. Blackman and Blair, {C. D.} and Blair, {D. G.} and Blair, {R. M.} and O. Blanch and F. Bobba and N. Bode and M. Boer and Y. Boetzel and G. Bogaert and M. Boldrini and F. Bondu and E. Bonilla and R. Bonnand and P. Booker and Boom, {B. A.} and R. Bork and V. Boschi and S. Bose and V. Bossilkov and V. Boudart and Y. Bouffanais and A. Bozzi and C. Bradaschia and Brady, {P. R.} and A. Bramley and M. Branchesi and Brau, {J. E.} and M. Breschi and T. Briant and Briggs, {J. H.} and F. Brighenti and A. Brillet and M. Brinkmann and P. Brockill and Brooks, {A. F.} and J. Brooks and Brown, {D. D.} and S. Brunett and G. Bruno and R. Bruntz and A. Buikema and T. Bulik and Bulten, {H. J.} and A. Buonanno and R. Buscicchio and D. Buskulic and Byer, {R. L.} and M. Cabero and L. Cadonati and M. Caesar and G. Cagnoli and C. Cahillane and {Calder{\'o}n Bustillo}, J. and Callaghan, {J. D.} and Callister, {T. A.} and E. Calloni and Camp, {J. B.} and M. Canepa and Cannon, {K. C.} and H. Cao and J. Cao and G. Carapella and F. Carbognani and Carney, {M. F.} and M. Carpinelli and G. Carullo and Carver, {T. L.} and {Casanueva Diaz}, J. 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 E. Cesarini and W. Chaibi and K. Chakravarti and C. Chan and C. Chan and K. Chandra and P. Chanial and S. Chao and P. Charlton and Chase, {E. A.} and E. Chassande-Mottin and D. Chatterjee and D. Chattopadhyay and M. Chaturvedi and K. Chatziioannou and A. Chen and Chen, {H. Y.} and X. Chen and Y. Chen and Cheng, {H. P.} and Cheong, {C. K.} and Chia, {H. Y.} and F. Chiadini and R. Chierici and A. Chincarini and A. Chiummo and G. Cho and Cho, {H. S.} and M. Cho and S. Choate and N. Christensen and Q. Chu and S. Chua and Chung, {K. W.} and S. Chung and G. Ciani and P. Ciecielag and M. Cie{\'s}lar and M. Cifaldi and Ciobanu, {A. A.} and R. Ciolfi and F. Cipriano and A. Cirone and F. Clara and Clark, {E. N.} and Clark, {J. A.} and L. Clarke and P. Clearwater and S. Clesse and F. Cleva and E. Coccia and Cohadon, {P. F.} and Cohen, {D. E.} and M. Colleoni and Collette, {C. G.} and C. Collins and M. Colpi and M. Constancio and L. Conti and M. Thomas",

note = "Publisher Copyright: {\textcopyright} 2021 authors. Published by the American Physical Society.",

year = "2021",

month = jun,

doi = "10.1103/PhysRevX.11.021053",

language = "English",

volume = "11",

pages = "1--52",

journal = "Physical Review X",

issn = "2160-3308",

publisher = "American Physical Society",

number = "2",

}