Swift /UVOT follow-up of gravitational wave alerts in the O3 era

Journal Article · 04 August 2021 · Monthly Notices of the Royal Astronomical Society

DOI: https://doi.org/10.1093/mnras/stab2189 · OSTI ID:1814652

Oates, S. R.  ^[1]; Marshall, F. E. ^[2]; Breeveld, A. A. ^[3]; Kuin, N. P. M.  ^[3]; Brown, P. J. ^[4]; De Pasquale, M. ^[5]; Evans, P. A.  ^[6]; Fenney, A. J. ^[3]; Gronwall, C. ^[7]; Kennea, J. A.  ^[8]; Klingler, N. J. ^[8]; Page, M. J. ^[3]; Siegel, M. H. ^[8]; Tohuvavohu, A. ^[9]; Ambrosi, E. ^[10]; Barthelmy, S. D. ^[2]; Beardmore, A. P.  ^[6]; Bernardini, M. G. ^[11]; Campana, S. ^[11]; Caputo, R. ^[2] ; Cenko, S. B. ^[12]; Cusumano, G.  ^[10]; D’Aì, A. ^[10]; D’Avanzo, P. ^[11]; D’Elia, V. ^[13]; Giommi, P.  ^[14]; Hartmann, D. H. ^[15]; Krimm, H. A. ^[16]; Laha, S. ^[17]; Malesani, D. B. ^[18]; Melandri, A.  ^[11]; Nousek, J. A. ^[8]; O’Brien, P. T. ^[6]; Osborne, J. P. ^[6]; Pagani, C. ^[6]; Page, K. L.  ^[6]; Palmer, D. M. ^[19]; Perri, M. ^[13]; Racusin, J. L. ^[2]; Sakamoto, T. ^[20]; Sbarufatti, B. ^[21]; Schlieder, J. E. ^[2]; Tagliaferri, G. ^[11]; Troja, E. ^[22]

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1. School of Physics and Astronomy & Institute for Gravitational Wave Astronomy, University of Birmingham, Birmingham B15 2TT, UK, University College London, Mullard Space Science Laboratory, Holmbury St. Mary, Dorking RH5 6NT, UK, Department of Physics, University of Warwick, Coventry CV4 7AL, UK
2. Astrophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
3. University College London, Mullard Space Science Laboratory, Holmbury St. Mary, Dorking RH5 6NT, UK
4. George P. and Cynthia Woods Mitchell Institute for Fundamental Physics and Astronomy, Mitchell Physics Building, Texas A.&M. University, Department of Physics and Astronomy, College Station, TX 77843, USA
5. Department of Astronomy and Space Sciences, Istanbul University, Beyazıt, 34119, Istanbul, Turkey
6. School of Physics and Astronomy, University of Leicester, Leicester LE1 7RH, UK
7. Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA 16802, USA, Institute for Gravitation and the Cosmos, The Pennsylvania State University, University Park, PA 16802, USA
8. Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA 16802, USA
9. Department of Astronomy and Astrophysics, University of Toronto, Toronto, ON M5S 3H4, Canada
10. INAF, IASF Palermo, Via Ugo La Malfa 153, I-90146, Palermo, Italy
11. INAF, Osservatorio Astronomico di Brera, Via Bianchi 46, I-23807 Merate, Italy
12. Astrophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA, Joint Space-Science Institute, Computer and Space Sciences Building, University of Maryland, College Park, MD 20742, USA
13. INAF, Osservatorio Astronomico di Roma, Via Frascati 33, I-00040 Monteporzio Catone, Italy, Space Science Data Center (SSDC), Agenzia Spaziale Italiana (ASI), I-00133 Roma, Italy
14. Space Science Data Center (SSDC), Agenzia Spaziale Italiana (ASI), I-00133 Roma, Italy
15. Department of Physics and Astronomy, Clemson University, Kinard Lab of Physics, Clemson, SC 29634, USA
16. National Science Foundation, Alexandria, VA 22314, USA
17. Astrophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA, Center for Space Science and Technology, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250, USA
18. DTU Space, National Space Institute, Technical University of Denmark, Elektrovej 327, DK-2800 Kongens Lyngby, Denmark
19. Los Alamos National Laboratory, B244, Los Alamos, NM, 87545, USA
20. Department of Physics and Mathematics, Aoyama Gakuin University, Sagamihara, Kanagawa, 252-5258, Japan
21. Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA 16802, USA, INAF, Osservatorio Astronomico di Brera, Via Bianchi 46, I-23807 Merate, Italy
22. Astrophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA, Department of Physics and Astronomy, University of Maryland, College Park, MD 20742, USA

ABSTRACT In this paper, we report on the observational performance of the Swift Ultra-violet/Optical Telescope (UVOT) in response to the gravitational wave (GW) alerts announced by the Advanced Laser Interferometer Gravitational Wave Observatory and the Advanced Virgo detector during the O3 period. We provide the observational strategy for follow-up of GW alerts and provide an overview of the processing and analysis of candidate optical/UV sources. For the O3 period, we also provide a statistical overview and report on serendipitous sources discovered by Swift/UVOT. Swift followed 18 GW candidate alerts, with UVOT observing a total of 424 deg2. We found 27 sources that changed in magnitude at the 3σ level compared with archival u- or g-band catalogued values. Swift/UVOT also followed up a further 13 sources reported by other facilities during the O3 period. Using catalogue information, we divided these 40 sources into five initial classifications: 11 candidate active galactic nuclei (AGNs)/quasars, three cataclysmic variables (CVs), nine supernovae, 11 unidentified sources that had archival photometry, and six uncatalogued sources for which no archival photometry was available. We have no strong evidence to identify any of these transients as counterparts to the GW events. The 17 unclassified sources are likely a mix of AGN and a class of fast-evolving transient, and one source may be a CV.

• Sponsoring Organization: USDOE
• OSTI ID: 1814652
• Journal Information: Monthly Notices of the Royal Astronomical Society, Journal Name: Monthly Notices of the Royal Astronomical Society Journal Issue: 1 Vol. 507; ISSN 0035-8711
• Publisher: Oxford University PressCopyright Statement
• Country of Publication: United Kingdom
• Language: English