KEGS/HiTS Discovery of a Young Type Ia Supernova in the K2 Campaign 5 Field.
ATel #7664; A. Zenteno (CTIO), F. Forster (CMM, MAS), A. Rest (STScI), S. Margheim (Gemini), B. Tucker (ANU/UCB), P. Garnavich (Notre Dame), D. Kasen (UCB/LBL), R. Olling, E. Shaya, R. Mushotzky (Maryland), T. GonÃ§alves (UFRJ), A. Bonaca (Yale), J. C. Maureira (CMM), L. Magill, A. Cardwell, and P. Candia (Gemini)
on 19 Jun 2015; 01:50 UT
Credential Certification: Brad Tucker (email@example.com)
Subjects: Optical, Supernovae
KEGS, the Kepler Extra-Galactic Survey, reports the discovery of a supernova candidate (KSN-2015a, RA: 8:23:50.14, DEC: 11:32:56.17) using the Dark Energy Camera (DECam, NOAO 2015A-0397 and 2015A-0371) on the 4m Blanco Telescope at Cerro Tololo (CTIO). The data analysis was performed using the High Cadence Transient Survey (ATELs #5949, #5956) pipeline, developed at the Center for Mathematical Modelling (CMM) in collaboration with the Millennium Institute for Astrophysics (MAS), using computation resources from the National Laboratory for High Performance Computing (NLHPC). The supernova was visible in an i-band image taken on 2015-06-03 with a magnitude of 18.49 +- 0.02, but was not visible on 2015-04-06. The reported magnitude is based on the difference with respect to the reference image taken on 2015-04-06. Spectroscopy was obtained on June 17.96 UT with the Gemini-South Telescope on Cerro Pachon with GMOS-S (GS-2015A-Q-33). Cross-correlation with a library of supernova spectra, the "Supernova Identification" code (SNID; Blondin and Tonry 2007, Ap.J. 666, 1024), confirmed KSN-2015a as a type Ia supernova just before maximum light (best fit is 03cg at -2 days) with z=0.034. The Kepler extended mission (K2) is currently monitoring the field that includes KSN-2015a using a 30-minute cadence but a single broad filter. Multi-color observations of this event are encouraged.