The SPIRITS Sample of Luminous Infrared Transients: Uncovering Hidden Supernovae and Dusty Stellar Outbursts in Nearby Galaxies
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Final Published Version
Affiliation
Univ Arizona, Steward ObservIssue Date
2019-11-18Keywords
dust, extinctioninfrared: general
stars: massive
supernovae: general
supernovae: individual (SPIRITS 14buu, SPIRITS 15c, SPIRITS 15ud, SPIRITS 16ix; SPIRITS 16tn, SPIRITS 17lb)
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IOP PUBLISHING LTDCitation
Jacob E. Jencson et al 2019 ApJ 886 40Journal
ASTROPHYSICAL JOURNALRights
Copyright © 2019. The American Astronomical Society. All rights reserved.Collection Information
This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at repository@u.library.arizona.edu.Abstract
We present a systematic study of the most luminous (M-IR [Vega magnitudes] brighter than ?14) infrared (IR) transients discovered by the SPitzer InfraRed Intensive Transients Survey (SPIRITS) between 2014 and 2018 in nearby galaxies (D < 35 Mpc). The sample consists of nine events that span peak IR luminosities of M-[4.5],M-peak between ?14 and ?18.2, show IR colors between 0.2;<;([3.6]?[4.5]);<;3.0, and fade on timescales between 55 days;t(fade);<;480 days. The two reddest events (A(V) > 12) show multiple, luminous IR outbursts over several years and have directly detected, massive progenitors in archival imaging. With analyses of extensive, multiwavelength follow-up, we suggest the following possible classifications: five obscured core-collapse supernovae (CCSNe), two erupting massive stars, one luminous red nova, and one intermediate-luminosity red transient. We define a control sample of all optically discovered transients recovered in SPIRITS galaxies and satisfying the same selection criteria. The control sample consists of eight CCSNe and one Type;Iax SN. We find that 7 of the 13 CCSNe in the SPIRITS sample have lower bounds on their extinction of 2;A(V);<;8. We estimate a nominal fraction of CCSNe in nearby galaxies that are missed by optical surveys as high as <CDATA<i (90% confidence). This study suggests that a significant fraction of CCSNe may be heavily obscured by dust and therefore undercounted in the census of nearby CCSNe from optical searches.ISSN
0004-637XVersion
Final published versionSponsors
National Aeronautics and Space AdministrationNational Aeronautics & Space Administration (NASA); National Science FoundationNational Science Foundation (NSF)Scopus Count
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