@article{f326177a77554861abbf16299ced120f,
title = "Search for gravitational waves from Scorpius X-1 with a hidden Markov model in O3 LIGO data",
abstract = "Results are presented for a semicoherent search for continuous gravitational waves from the low-mass x-ray binary Scorpius X-1, using a hidden Markov model (HMM) to allow for spin wandering. This search improves on previous HMM-based searches of Laser Interferometer Gravitational-Wave Observatory data by including the orbital period in the search template grid, and by analyzing data from the latest (third) observing run. In the frequency range searched, from 60 to 500 Hz, we find no evidence of gravitational radiation. This is the most sensitive search for Scorpius X-1 using a HMM to date. For the most sensitive subband, starting at 256.06 Hz, we report an upper limit on gravitational wave strain (at 95\% confidence) of h095\%=6.16×10-26, assuming the orbital inclination angle takes its electromagnetically restricted value ι=44°. The upper limits on gravitational wave strain reported here are on average a factor of ∼3 lower than in the second observing run HMM search. This is the first Scorpius X-1 HMM search with upper limits that reach below the indirect torque-balance limit for certain subbands, assuming ι=44°.",
author = "R. Abbott and H. Abe and F. Acernese and K. Ackley and N. Adhikari and Adhikari, \{R. X.\} and Adkins, \{V. K.\} and Adya, \{V. B.\} and C. Affeldt and D. Agarwal and M. Agathos and K. Agatsuma and N. Aggarwal and Aguiar, \{O. D.\} and L. Aiello and A. Ain and P. Ajith and T. Akutsu and S. Albanesi and Alfaidi, \{R. A.\} and A. Allocca and Altin, \{P. A.\} and A. Amato and C. Anand and S. Anand and A. Ananyeva and Anderson, \{S. B.\} and Anderson, \{W. G.\} and M. Ando and T. Andrade and N. Andres and M. Andr{\'e}s-Carcasona and T. Andri{\'c} and Angelova, \{S. V.\} and S. Ansoldi and Antelis, \{J. M.\} and S. Antier and T. Apostolatos and Appavuravther, \{E. Z.\} and S. Appert and Apple, \{S. K.\} and K. Arai and A. Araya and Araya, \{M. C.\} and Areeda, \{J. S.\} and C. Badger and Chung, \{K. W.\} and Jenkins, \{A. C.\} and K. Martinovic and M. Sakellariadou and \{(LIGO Scientific Collaboration, Virgo Collaboration, and KAGRA Collaboration)\}",
note = "Funding Information: This material is based upon work supported by NSF{\textquoteright}s LIGO Laboratory which is a major facility fully funded by the National Science Foundation. The authors also gratefully acknowledge the support of the Science and Technology Facilities Council (STFC) of the United Kingdom, the Max-Planck-Society (MPS), and the State of Niedersachsen/Germany for support of the construction of Advanced LIGO and construction and operation of the GEO 600 detector. Additional support for Advanced LIGO was provided by the Australian Research Council. The authors gratefully acknowledge the Italian Istituto Nazionale di Fisica Nucleare (INFN), the French Centre National de la Recherche Scientifique (CNRS), and the Netherlands Organization for Scientific Research (NWO), for the construction and operation of the Virgo detector and the creation and support of the EGO consortium. The authors also gratefully acknowledge research support from these agencies as well as by the Council of Scientific and Industrial Research of India, the Department of Science and Technology, India, the Science and Engineering Research Board (SERB), India, the Ministry of Human Resource Development, India, the Spanish Agencia Estatal de Investigaci{\'o}n (AEI), the Spanish Ministerio de Ciencia e Innovaci{\'o}n and Ministerio de Universidades, the Conselleria de Fons Europeus, Universitat i Cultura and the Direcci{\'o} General de Pol{\'i}tica Universitaria i Recerca del Govern de les Illes Balears, the Conselleria d{\textquoteright}Innovaci{\'o}, Universitats, Ci{\`e}ncia i Societat Digital de la Generalitat Valenciana, and the CERCA Programme Generalitat de Catalunya, Spain, the National Science Centre of Poland, and the European Union—European Regional Development Fund; Foundation for Polish Science (FNP), the Swiss National Science Foundation (SNSF), the Russian Foundation for Basic Research, the Russian Science Foundation, the European Commission, the European Social Funds (ESF), the European Regional Development Funds (ERDF), the Royal Society, the Scottish Funding Council, the Scottish Universities Physics Alliance, the Hungarian Scientific Research Fund (OTKA), the French Lyon Institute of Origins (LIO), the Belgian Fonds de la Recherche Scientifique (FRS-FNRS), Actions de Recherche Concert{\'e}es (ARC) and Fonds Wetenschappelijk Onderzoek—Vlaanderen (FWO), Belgium, the Paris {\^I}le-de-France Region, the National Research, Development and Innovation Office Hungary (NKFIH), the National Research Foundation of Korea, the Natural Science and Engineering Research Council Canada, Canadian Foundation for Innovation (CFI), the Brazilian Ministry of Science, Technology, and Innovations, the International Center for Theoretical Physics South American Institute for Fundamental Research (ICTP-SAIFR), the Research Grants Council of Hong Kong, the National Natural Science Foundation of China (NSFC), the Leverhulme Trust, the Research Corporation, the Ministry of Science and Technology (MOST), Taiwan, the U.S. Department of Energy, and the Kavli Foundation. The authors gratefully acknowledge the support of the NSF, STFC, INFN, and CNRS for provision of computational resources. This work was supported by MEXT, JSPS Leading-edge Research Infrastructure Program, JSPS Grant-in-Aid for Specially Promoted Research 26000005, JSPS Grant-in-Aid for Scientific Research on Innovative Areas 2905: JP17H06358, JP17H06361, and JP17H06364, JSPS Core-to-Core Program A. Advanced Research Networks, JSPS Grant-in-Aid for Scientific Research (S) 17H06133 and 20H05639, JSPS Grant-in-Aid for Transformative Research Areas (A) 20A203: JP20H05854, the joint research program of the Institute for Cosmic Ray Research, University of Tokyo, National Research Foundation (NRF), Computing Infrastructure Project of KISTI-GSDC, Korea Astronomy and Space Science Institute (KASI), and Ministry of Science and ICT (MSIT) in Korea, Academia Sinica (AS), AS Grid Center (ASGC) and the Ministry of Science and Technology (MoST) in Taiwan under grants including AS-CDA-105-M06, Advanced Technology Center (ATC) of NAOJ, and Mechanical Engineering Center of KEK. Publisher Copyright: {\textcopyright} 2022 American Physical Society. All rights reserved.",
year = "2022",
month = sep,
day = "21",
doi = "10.1103/PhysRevD.106.062002",
language = "English",
volume = "106",
journal = "Physical Review D",
issn = "2470-0010",
publisher = "American Physical Society (APS)",
number = "6",
}