@article{21afa70d32c44e56a7fc51e420ce973f,

title = "Search for continuous gravitational waves from neutron stars in globular cluster NGC 6544",

abstract = "We describe a directed search for continuous gravitational waves in data from the sixth initial LIGO science run. The target was the nearby globular cluster NGC 6544 at a distance of ≈2.7 kpc. The search covered a broad band of frequencies along with first and second frequency derivatives for a fixed sky position. The search coherently integrated data from the two LIGO interferometers over a time span of 9.2 days using the matched-filtering F-statistic. We found no gravitational-wave signals and set 95% confidence upper limits as stringent as 6.0×10-25 on intrinsic strain and 8.5×10-6 on fiducial ellipticity. These values beat the indirect limits from energy conservation for stars with characteristic spin-down ages older than 300 years and are within the range of theoretical predictions for possible neutron-star ellipticities. An important feature of this search was use of a barycentric resampling algorithm which substantially reduced computational cost; this method is used extensively in searches of Advanced LIGO and Virgo detector data.",

author = "{(LIGO Scientific Collaboration and Virgo Collaboration)} and Abbott, {B. P.} and R. Abbott and Abbott, {T. D.} and Abernathy, {M. R.} and F. Acernese and K. Ackley and C. Adams and T. Adams and P. Addesso 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 B. Allen and A. Allocca and Altin, {P. A.} and Anderson, {S. B.} and Anderson, {W. G.} and K. Arai and Araya, {M. C.} and Arceneaux, {C. C.} and Areeda, {J. S.} and N. Arnaud and Arun, {K. G.} and S. Ascenzi and G. Ashton and M. Ast and Aston, {S. M.} and P. Astone and P. Aufmuth and C. Aulbert and S. Babak and P. Bacon and Bader, {M. K.M.} and Baker, {P. T.} and F. Baldaccini and G. Ballardin and Ballmer, {S. W.} and Barayoga, {J. C.} and Barclay, {S. E.} and Barish, {B. C.} and D. Barker and F. Barone and B. Barr and Chunglee Kim",

note = "Publisher Copyright: {\textcopyright} 2017 American Physical Society.",

year = "2017",

month = apr,

day = "19",

doi = "10.1103/PhysRevD.95.082005",

language = "English",

volume = "95",

journal = "Physical Review D",

issn = "2470-0010",

publisher = "American Physical Society",

number = "8",

}