Transient 2018bsr

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Robin Leadbeater

Hi David,

From the sharp H alpha emission line in the spectrum (from the host galaxy) the redshift = ~0.04 which corresponds to ~170MPc distance. The spectrum is clearly a type 1a. At this distance a type 1a SN would reach ~16.9 at maximum, not allowing for any redenning.  The ASAS-SN mag 17.2 does seem rather bright  for 9-12 days before maximum but ages estimated from the spectra can be notoriously unreliable so it could be closer to maximum than this