2012CBET.3171....1F

M. Fraser, R. Kotak, D. Wright, K. Smith, S. J. Smartt, L. Magill, and M. McCrum, Queens University, Belfast, report the discovery and spectroscopic classification of a supernova from the PanSTARRS-1 (PS1) Medium Deep Survey. The new object was discovered in the PS1 Medium Deep Survey at magnitude y = 20.3 ± 0.3 on June 27. The transient appears to be coincident with the nucleus of the SDSS galaxy J141346.13+521317.3 (thus at R.A. = 14:13:46.13, Decl. = +52:13:17.3, equinox 2000.0), with a redshift of 0.078. The variable was subsequently detected at magnitudes g = 19.5 on June 27 and z = 19.4 on June 30. An optical spectrogram of 2012dm was obtained by J. Jensen-Hansen with the Nordic Optical Telescope (+ ALFOSC + Grism#4; range 320-910 nm, resolution about 1.4 nm) on July 7. The spectrum of 2012dm is best matched by the SuperNova IDentification code (SNID; Blondin and Tonry 2007, Ap.J. 666, 1024) to a normal type-Ia supernova at five days after maximum light. The discovery of 2012dm was enabled using the PS1 System operated by the PS1 Science Consortium and its member institutions (see website URL http://www.ps1sc.org/PS1_System_ATel.htm); the authors thank the PS1 telescope operators for their support of PS1 observations.