TY - JOUR
T1 - Discovery of the Luminous, Decades-long, Extragalactic Radio Transient FIRST J141918.9+394036
AU - Law, C. J.
AU - Gaensler, B. M.
AU - Metzger, B. D.
AU - Ofek, E. O.
AU - Sironi, L.
N1 - We thank Rick Perley, Tom Osterloo, Jamie Farnes, Amy Kimball, Joe Callingham, Dustin Lang and Kevin Hurley for assistance with archival data, Steve Croft, Geoff Bower, Xavier Prochaska, Dovi Poznanski, and Hendrik Van Eerten for helpful comments, and the NASA Swift team for prompt scheduling of observations. C.J.L. acknowledges support from the National Science Foundation under grant 1611606. The Dunlap Institute is funded through an endowment established by the David Dunlap family and the University of Toronto. B.M.G. acknowledges the support of the Natural Sciences and Engineering Research Council of Canada (NSERC) through grant RGPIN-2015-05948, and of the Canada Research Chairs program. B.D.M. acknowledges the support of NASA through the Astrophysics Theory Program through grant NNX16AB30G. E.O.O. is grateful for support by grants from the Israeli Ministry of Science, Minerva, BSF, BSF transformative program, Weizmann-UK, and the I-CORE Program of the Planning and Budgeting Committee and the Israel Science Foundation (grant No. 1829/12). L.S. acknowledges the support of NSF through grant AST-1716567. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. The Pan-STARRS1 Surveys (PS1) and the PS1 public science archive have been made possible through contributions by the Institute for Astronomy, the University of Hawaii, and others. Funding for the Sloan Digital Sky Survey IV has been provided by the Alfred P. Sloan Foundation, the U.S. Department of Energy Office of Science, and the Participating Institutions. SDSS acknowledges support and resources from the Center for High-Performance Computing at the University of Utah. The SDSS web site is http://www.sdss.org. This research has made use of: the SIMBAD database, operated at Centre de Données astronomiques de Strasbourg, France; the NASA/IPAC Extragalactic Database (NED) which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA; NASA's Astrophysics Data System; and the VizieR catalog access tool, CDS, Strasbourg, France, as originally described by Ochsenbein et al. (2000). This research has made use of data and/or software provided by the High Energy Astrophysics Science Archive Research Center (HEASARC), which is a service of the Astrophysics Science Division at NASA/GSFC and the High Energy Astrophysics Division of the Smithsonian Astrophysical Observatory.
PY - 2018/10/20
Y1 - 2018/10/20
N2 - We present the discovery of a slowly evolving, extragalactic radio transient, FIRST J141918.9+394036, identified by comparing a catalog of radio sources in nearby galaxies against new observations from the Very Large Array Sky Survey. Analysis of other archival data shows that FIRST J141918.9+394036 faded by a factor of ∼50 over 23 years, from a flux of ∼26 mJy at 1.4 GHz in 1993 to an upper limit of 0.4 mJy at 3 GHz in 2017. FIRST J141918.9+394036 is likely associated with the small star-forming galaxy SDSS J141918.81+394035.8 at a redshift z = 0.01957 (d = 87 Mpc), which implies a peak luminosity νL ν 3 × 1038 erg s-1. If interpreted as an isotropic synchrotron blast wave, the source requires an explosion of kinetic energy ∼1051 erg some time prior to our first detection in late 1993. This explosion is most likely associated with a long gamma-ray burst (GRB), but the radio source could also be interpreted as the nebula of a newly born magnetar. The radio discovery of either of these phenomena would be unprecedented. Joint consideration of the event light curve, host galaxy, lack of a counterpart GRB, and volumetric rate suggests that FIRST J141918.9+394036 is the afterglow of an off-axis ("orphan") long GRB. The long time baseline of this event offers the best available constraint in afterglow evolution as the bulk of shock-accelerated electrons become non-relativistic. The proximity, age, and precise localization of FIRST J141918.9+394036 make it a key object for understanding the aftermath of rare classes of stellar explosion.
AB - We present the discovery of a slowly evolving, extragalactic radio transient, FIRST J141918.9+394036, identified by comparing a catalog of radio sources in nearby galaxies against new observations from the Very Large Array Sky Survey. Analysis of other archival data shows that FIRST J141918.9+394036 faded by a factor of ∼50 over 23 years, from a flux of ∼26 mJy at 1.4 GHz in 1993 to an upper limit of 0.4 mJy at 3 GHz in 2017. FIRST J141918.9+394036 is likely associated with the small star-forming galaxy SDSS J141918.81+394035.8 at a redshift z = 0.01957 (d = 87 Mpc), which implies a peak luminosity νL ν 3 × 1038 erg s-1. If interpreted as an isotropic synchrotron blast wave, the source requires an explosion of kinetic energy ∼1051 erg some time prior to our first detection in late 1993. This explosion is most likely associated with a long gamma-ray burst (GRB), but the radio source could also be interpreted as the nebula of a newly born magnetar. The radio discovery of either of these phenomena would be unprecedented. Joint consideration of the event light curve, host galaxy, lack of a counterpart GRB, and volumetric rate suggests that FIRST J141918.9+394036 is the afterglow of an off-axis ("orphan") long GRB. The long time baseline of this event offers the best available constraint in afterglow evolution as the bulk of shock-accelerated electrons become non-relativistic. The proximity, age, and precise localization of FIRST J141918.9+394036 make it a key object for understanding the aftermath of rare classes of stellar explosion.
UR - http://www.scopus.com/inward/record.url?scp=85055294664&partnerID=8YFLogxK
U2 - https://doi.org/10.3847/2041-8213/aae5f3
DO - https://doi.org/10.3847/2041-8213/aae5f3
M3 - مقالة
SN - 2041-8205
VL - 866
JO - Astrophysical Journal Letters
JF - Astrophysical Journal Letters
IS - 2
M1 - L22
ER -