FLOYDS Classification of ASASSN-17qg/AT 2017isj as a Young Type Ia Supernova
ATel #11032; G. Hosseinzadeh, I. Arcavi, D. A. Howell, C. McCully (Las Cumbres Obs./UCSB), S. Valenti (UC Davis)
on 4 Dec 2017; 19:50 UT
Distributed as an Instant Email Notice Supernovae
Credential Certification: Griffin Hosseinzadeh (griffin@lco.global)
Subjects: Optical, Supernovae
We obtained a spectrum of ASASSN-17qg/AT 2017isj on 2017 December 4.5 UT with the robotic FLOYDS instrument mounted on the Las Cumbres Observatory 2-meter telescope on Haleakala, Hawai'i. Using Superfit (Howell et al. 2005, ApJ, 634, 1190), we find good fits to several Type Ia supernovae 0-2 weeks before maximum light at a redshift of the proposed host galaxy (z=0.019; Falco et al. 1999, PASP, 111, 438 via NED). We measure a Si II velocity of about 16,000 km/s, implying the supernova was discovered soon after explosion, but the absolute magnitude at discovery was about -19, implying it was discovered near maximum light. Together, these could either indicate a young overluminous supernova or a high-velocity supernova at peak. The spectrum is available on the Transient Name Server.
