The Astrophysical Journal (Jan 2023)
A Search for Extragalactic Fast Blue Optical Transients in ZTF and the Rate of AT2018cow-like Transients
- Anna Y. Q. Ho,
- Daniel A. Perley,
- Avishay Gal-Yam,
- Ragnhild Lunnan,
- Jesper Sollerman,
- Steve Schulze,
- Kaustav K. Das,
- Dougal Dobie,
- Yuhan Yao,
- Christoffer Fremling,
- Scott Adams,
- Shreya Anand,
- Igor Andreoni,
- Eric C. Bellm,
- Rachel J. Bruch,
- Kevin B. Burdge,
- Alberto J. Castro-Tirado,
- Aishwarya Dahiwale,
- Kishalay De,
- Richard Dekany,
- Andrew J. Drake,
- Dmitry A. Duev,
- Matthew J. Graham,
- George Helou,
- David L. Kaplan,
- Viraj Karambelkar,
- Mansi M. Kasliwal,
- Erik C. Kool,
- S. R. Kulkarni,
- Ashish A. Mahabal,
- Michael S. Medford,
- A. A. Miller,
- Jakob Nordin,
- Eran Ofek,
- Glen Petitpas,
- Reed Riddle,
- Yashvi Sharma,
- Roger Smith,
- Adam J. Stewart,
- Kirsty Taggart,
- Leonardo Tartaglia,
- Anastasios Tzanidakis,
- Jan Martin Winters
Affiliations
- Anna Y. Q. Ho
- ORCiD
- Miller Institute for Basic Research in Science , 468 Donner Lab, Berkeley, CA 94720, USA ; [email protected]; Department of Astronomy, University of California , Berkeley, 501 Campbell Hall, Berkeley, CA, 94720, USA; Lawrence Berkeley National Laboratory , 1 Cyclotron Road, MS 50B-4206, Berkeley, CA 94720, USA; Department of Astronomy, Cornell University , Ithaca, NY 14853, USA
- Daniel A. Perley
- ORCiD
- Astrophysics Research Institute, Liverpool John Moores University , IC2, Liverpool Science Park, 146 Brownlow Hill, Liverpool L3 5RF, UK
- Avishay Gal-Yam
- ORCiD
- Department of Particle Physics and Astrophysics, Weizmann Institute of Science , 234 Herzl St., 76100 Rehovot, Israel
- Ragnhild Lunnan
- ORCiD
- The Oskar Klein Centre, Department of Astronomy, Stockholm University , AlbaNova, SE-10691 Stockholm, Sweden
- Jesper Sollerman
- ORCiD
- The Oskar Klein Centre, Department of Astronomy, Stockholm University , AlbaNova, SE-10691 Stockholm, Sweden
- Steve Schulze
- ORCiD
- The Oskar Klein Centre, Department of Astronomy, Stockholm University , AlbaNova, SE-10691 Stockholm, Sweden
- Kaustav K. Das
- ORCiD
- Cahill Center for Astrophysics, California Institute of Technology , MC 249-17, 1200 E. California Boulevard, Pasadena, CA, 91125, USA
- Dougal Dobie
- ORCiD
- Centre for Astrophysics and Supercomputing, Swinburne University of Technology , Hawthorn, Victoria, Australia; ARC Centre of Excellence for Gravitational Wave Discovery (OzGrav) , Hawthorn, Victoria, Australia
- Yuhan Yao
- ORCiD
- Cahill Center for Astrophysics, California Institute of Technology , MC 249-17, 1200 E. California Boulevard, Pasadena, CA, 91125, USA
- Christoffer Fremling
- ORCiD
- Cahill Center for Astrophysics, California Institute of Technology , MC 249-17, 1200 E. California Boulevard, Pasadena, CA, 91125, USA
- Scott Adams
- Cahill Center for Astrophysics, California Institute of Technology , MC 249-17, 1200 E. California Boulevard, Pasadena, CA, 91125, USA
- Shreya Anand
- ORCiD
- Division of Physics, Mathematics and Astronomy, California Institute of Technology , Pasadena, CA 91125, USA
- Igor Andreoni
- ORCiD
- Cahill Center for Astrophysics, California Institute of Technology , MC 249-17, 1200 E. California Boulevard, Pasadena, CA, 91125, USA
- Eric C. Bellm
- ORCiD
- DIRAC Institute, Department of Astronomy, University of Washington , 3910 15th Avenue NE, Seattle, WA 98195, USA
- Rachel J. Bruch
- ORCiD
- Department of Particle Physics and Astrophysics Weizmann Institute of Science 234 Herzl St., 76100 Rehovot, Israel
- Kevin B. Burdge
- ORCiD
- Division of Physics, Mathematics and Astronomy, California Institute of Technology , Pasadena, CA 91125, USA
- Alberto J. Castro-Tirado
- ORCiD
- Instituto de Astrofísica de Andalucía (IAA-CSIC) Glorieta de la Astronomia E-18008, Granada, Spain
- Aishwarya Dahiwale
- Cahill Center for Astrophysics, California Institute of Technology , MC 249-17, 1200 E. California Boulevard, Pasadena, CA, 91125, USA
- Kishalay De
- Cahill Center for Astrophysics, California Institute of Technology , MC 249-17, 1200 E. California Boulevard, Pasadena, CA, 91125, USA
- Richard Dekany
- ORCiD
- Caltech Optical Observatories, California Institute of Technology , Pasadena, CA 91125, USA
- Andrew J. Drake
- ORCiD
- Cahill Center for Astrophysics, California Institute of Technology , MC 249-17, 1200 E. California Boulevard, Pasadena, CA, 91125, USA
- Dmitry A. Duev
- ORCiD
- Division of Physics, Mathematics, and Astronomy, California Institute of Technology , Pasadena, CA 91125, USA
- Matthew J. Graham
- ORCiD
- Cahill Center for Astrophysics, California Institute of Technology , MC 249-17, 1200 E. California Boulevard, Pasadena, CA, 91125, USA
- George Helou
- ORCiD
- IPAC, California Institute of Technology , 1200 E. California Blvd., Pasadena, CA 91125, USA
- David L. Kaplan
- ORCiD
- Center for Gravitation, Cosmology, and Astrophysics, Department of Physics, University of Wisconsin-Milwaukee , P.O. Box 413, Milwaukee, WI 53201, USA
- Viraj Karambelkar
- ORCiD
- Cahill Center for Astrophysics, California Institute of Technology , MC 249-17, 1200 E. California Boulevard, Pasadena, CA, 91125, USA
- Mansi M. Kasliwal
- ORCiD
- Cahill Center for Astrophysics, California Institute of Technology , MC 249-17, 1200 E. California Boulevard, Pasadena, CA, 91125, USA
- Erik C. Kool
- ORCiD
- The Oskar Klein Centre, Department of Astronomy, Stockholm University , AlbaNova, SE-10691 Stockholm, Sweden
- S. R. Kulkarni
- ORCiD
- Cahill Center for Astrophysics, California Institute of Technology , MC 249-17, 1200 E. California Boulevard, Pasadena, CA, 91125, USA
- Ashish A. Mahabal
- ORCiD
- Division of Physics, Mathematics and Astronomy, California Institute of Technology , Pasadena, CA 91125, USA; Center for Data Driven Discovery, California Institute of Technology , Pasadena, CA 91125, USA
- Michael S. Medford
- ORCiD
- Department of Astronomy, University of California , Berkeley, Berkeley, CA 94720, USA; Lawrence Berkeley National Laboratory, 1 Cyclotron Rd., Berkeley, CA 94720, USA
- A. A. Miller
- ORCiD
- Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA) and Department of Physics and Astronomy, Northwestern University , 1800 Sherman Road, Evanston, IL 60201, USA; The Adler Planetarium, Chicago, IL 60605, USA
- Jakob Nordin
- ORCiD
- Institute of Physics, Humboldt-Universität zu Berlin , Newtonstr. 15, D-12489 Berlin, Germany
- Eran Ofek
- ORCiD
- Department of Particle Physics and Astrophysics, Weizmann Institute of Science , 234 Herzl St., 76100 Rehovot, Israel
- Glen Petitpas
- Harvard-Smithsonian Center for Astrophysics , 60 Garden Street, Cambridge, MA 02138, USA
- Reed Riddle
- ORCiD
- Caltech Optical Observatories, California Institute of Technology , Pasadena, CA 91125, USA
- Yashvi Sharma
- ORCiD
- Cahill Center for Astrophysics, California Institute of Technology , MC 249-17, 1200 E. California Boulevard, Pasadena, CA, 91125, USA
- Roger Smith
- ORCiD
- Caltech Optical Observatories, California Institute of Technology , Pasadena, CA 91125, USA
- Adam J. Stewart
- ORCiD
- Sydney Institute for Astronomy, School of Physics, The University of Sydney , NSW 2006, Australia
- Kirsty Taggart
- Department of Astronomy and Astrophysics, University of California , Santa Cruz, CA 95064, USA
- Leonardo Tartaglia
- ORCiD
- The Oskar Klein Centre , Department of Astronomy, AlbaNova, SE-106 91 Stockholm, Sweden; INAF—Osservatorio Astronomico di Padova , Vicolo dell’Osservatorio 5, I-35122 Padova, Italy
- Anastasios Tzanidakis
- ORCiD
- Cahill Center for Astrophysics, California Institute of Technology , MC 249-17, 1200 E. California Boulevard, Pasadena, CA, 91125, USA
- Jan Martin Winters
- ORCiD
- Institut de Radioastronomie Millimétrique (IRAM) , 300 rue de la Piscine, F-38406 St. Martin d’Héres, France
- DOI
- https://doi.org/10.3847/1538-4357/acc533
- Journal volume & issue
-
Vol. 949,
no. 2
p. 120
Abstract
We present a search for extragalactic fast blue optical transients (FBOTs) during Phase I of the Zwicky Transient Facility (ZTF). We identify 38 candidates with durations above half-maximum light 1 day < t _1/2 < 12 days, of which 28 have blue ( g − r ≲ −0.2 mag) colors at peak light. Of the 38 transients (28 FBOTs), 19 (13) can be spectroscopically classified as core-collapse supernovae (SNe): 11 (8) H- or He-rich (Type II/IIb/Ib) SNe, 6 (4) interacting (Type IIn/Ibn) SNe, and 2 (1) H&He-poor (Type Ic/Ic-BL) SNe. Two FBOTs (published previously) had predominantly featureless spectra and luminous radio emission: AT2018lug (The Koala) and AT2020xnd (The Camel). Seven (five) did not have a definitive classification: AT 2020bdh showed tentative broad H α in emission, and AT 2020bot showed unidentified broad features and was 10 kpc offset from the center of an early-type galaxy. Ten (eight) have no spectroscopic observations or redshift measurements. We present multiwavelength (radio, millimeter, and/or X-ray) observations for five FBOTs (three Type Ibn, one Type IIn/Ibn, one Type IIb). Additionally, we search radio-survey (VLA and ASKAP) data to set limits on the presence of radio emission for 24 of the transients. All X-ray and radio observations resulted in nondetections; we rule out AT2018cow-like X-ray and radio behavior for five FBOTs and more luminous emission (such as that seen in the Camel) for four additional FBOTs. We conclude that exotic transients similar to AT2018cow, the Koala, and the Camel represent a rare subset of FBOTs and use ZTF’s SN classification experiments to measure the rate to be at most 0.1% of the local core-collapse SN rate.
Keywords
