A Search for Kilonovae in the Dark Energy Survey

Journal Article · Wed Mar 01 00:00:00 EST 2017 · Astrophysical Journal

DOI:https://doi.org/10.3847/1538-4357/AA5D09· OSTI ID:22869267

Doctor, Z.; Kessler, R.; Chen, H. Y.; Farr, B.; Holz, D. E.; Scolnic, D. ^[1]; Finley, D. A.; Soares-Santos, M.; Allam, S.; Annis, J. ^[2]; Foley, R. J. ^[3]; Goldstein, D. A. ^[4]; Kim, A. G. ^[5]; Morganson, E. ^[6]; Sako, M. ^[7]; Smith, M. ^[8]; Spinka, H. ^[9]; Abbott, T. M. C. ^[10]; Abdalla, F. B. ^[11]; Bechtol, K. ^[12] ; others, and

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1. Kavli Institute for Cosmological Physics, University of Chicago, Chicago, IL 60637 (United States)
2. Fermi National Accelerator Laboratory, P.O. Box 500, Batavia, IL 60510 (United States)
3. Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States)
4. Department of Astronomy, University of California, Berkeley, 501 Campbell Hall, Berkeley, CA 94720 (United States)
5. Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States)
6. National Center for Supercomputing Applications, 1205 West Clark Street, Urbana, IL 61801 (United States)
7. Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104 (United States)
8. School of Physics and Astronomy, University of Southampton, Southampton, SO17 1BJ (United Kingdom)
9. Argonne National Laboratory, 9700 South Cass Avenue, Lemont, IL 60439 (United States)
10. Cerro Tololo Inter-American Observatory, National Optical Astronomy Observatory, Casilla 603, La Serena (Chile)
11. Department of Physics and Astronomy, University College London, Gower Street, London, WC1E 6BT (United Kingdom)
12. LSST, 933 North Cherry Avenue, Tucson, AZ 85721 (United States)

The coalescence of a binary neutron star pair is expected to produce gravitational waves (GW) and electromagnetic radiation, both of which may be detectable with currently available instruments. We describe a search for a predicted r-process optical transient from these mergers, dubbed the “kilonova” (KN), using griz broadband data from the Dark Energy Survey Supernova Program (DES-SN). Some models predict KNe to be redder, shorter-lived, and dimmer than supernovae (SNe), but the event rate of KNe is poorly constrained. We simulate KN and SN light curves with the Monte-Carlo simulation code SNANA to optimize selection requirements, determine search efficiency, and predict SN backgrounds. Our analysis of the first two seasons of DES-SN data results in 0 events, and is consistent with our prediction of 1.1 ± 0.2 background events based on simulations of SNe. From our prediction, there is a 33% chance of finding 0 events in the data. Assuming no underlying galaxy flux, our search sets 90% upper limits on the KN volumetric rate of 1.0 ×10{sup 7} Gpc{sup −3} yr{sup −1} for the dimmest KN model we consider (peak i-band absolute magnitude M{sub i}=−11.4 mag) and 2.4 ×10{sup 4} Gpc{sup −3} yr{sup −1} for the brightest (M{sub i}=−16.2 mag). Accounting for anomalous subtraction artifacts on bright galaxies, these limits are ∼3 times higher. This analysis is the first untriggered optical KN search and informs selection requirements and strategies for future KN searches. Our upper limits on the KN rate are consistent with those measured by GW and gamma-ray burst searches.

• OSTI ID: 22869267
• Journal Information: Astrophysical Journal, Vol. 837, Issue 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
COALESCENCE
COMPUTERIZED SIMULATION
COSMIC GAMMA BURSTS
DATA ANALYSIS
EFFICIENCY
FORECASTING
GALAXIES
GRAVITATIONAL WAVES
MONTE CARLO METHOD
NEUTRON STARS
NONLUMINOUS MATTER
R PROCESS
SUPERNOVAE