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GCN Circular 18790

LIGO/Virgo G211117: FLOYDS Classification of SMTJ13331687-1607330 as a Two-Week-Old Type Ia Supernova
2015-12-31T20:09:35Z (8 years ago)
Griffin Hosseinzadeh at LCOGT <>
G. Hosseinzadeh, I. Arcavi, D. A. Howell, C. McCully (LCOGT/UCSB), and S.
Valenti (UC Davis) report the classification of the EM candidate
SMTJ13331687-1607330 (GCN 18771) associated with gravitational wave event
G211117 (GCN 18728) based on a spectrum obtained 2015 December 31.6 UT with
the robotic FLOYDS instrument mounted on the Faulkes Telescope North. SNID
(Blondin & Tonry 2007, ApJ, 666, 1024) gives good fits to several normal
Type Ia supernovae around two weeks after maximum light at redshifts
consistent with that of the proposed host galaxy (z=0.020; Catinella,
Haynes, & Giovanelli 2005, AJ, 130, 1037 via NED). Since the LIGO trigger
occurred less than six days earlier on 2015 December 26.2,
SMTJ13331687-1607330 is likely unassociated with the gravitational wave
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