-------------------------------------------------------------------
THE ASTRONOMER Electronic Circular No 3153      2016 Mar 15 10.13UT
Ed:Guy M Hurst, 16,Westminster Close, Kempshott Rise,  Basingstoke,
Hants, RG22 4PP,England.Telephone/FAX(01256)471074Int:+441256471074
INTERNET: GUY@TAHQ.DEMON.CO.UK      Backup: gmh@wdcc1.bnsc.rl.ac.uk
WORLD WIDE WEB                         http://www.theastronomer.org
-------------------------------------------------------------------
SN 2016bau IN NGC 3631
Ron Arbour, South Wonston, England, reports the discovery, during searches
for the UK Nova/Supernova Patrol, of a magnitude 17.85V (unfiltered)
supernova in the galaxy NGC3631 on a CCD image taken on 2016 Mar 13.9741 UT
using a 0.35-m f/6 Schmidt Cassegrain Telescope and SXVF H9 CCD camera.

The object was also recorded on several subsequent images to a limiting
unfiltered magnitude of 18.9

Precise position: RA 11h 20m 59.02s DEC +53° 10' 25.6" (2000)

Offsets from galaxy: 35"W 15"N

The object was not visible on the Digitised Sky Survey POSS II Blue plate or
the POSS II Red plate, nor listed on CBAT's Minor Planet Checker.

The object was initially designated AT 2016bau pending spectral confirmation
now obtained (see below).

Denis Buczynski, Scotland, obtained an image on March 14 (20h59mUT) recorded
as magnitude 16.1 CR. He derived a position of:
RA 11h20m 59.19s DEC +53 10’26.0” (2000)

V. Granata et. al. report on ATEL 8818 on behalf of The Asiago Transient
Classification Program the spectroscopic classification of AT 2016bau. The
observation was performed with the Asiago 1.82 m Copernico Telescope
(+AFOSC; range 340-820 nm; resolution 1.4 nm).  

Adopting a redshift z=0.003856 for the host galaxy, a good match is found
with SN 2004gq, 7-10 days before the maximum light.
The early phase is supported by the high velocity expansion (about 16800
km/s) for the HeI 587.6 nm absorption. 

Based on AFOSC multi-band imaging, they measured the following apparent AB
magnitudes: u=18.87(0.03) mag, g=17.66(0.02) mag, r=17.50(0.03) mag,
i=17.49(0.03) mag, z=17.59(0.02) mag. 

Given the galaxy distance modulus (30.41 mag via NED) the absolute magnitude
reduces to -12.9 mag in r-band, at the very faint end of the Ib luminosity
function even considering the early phase. 

Classification was done with GELATO and SNID. The Asiago classification
spectra are posted at the website http://sngroup.oapd.inaf.it.  

Guy M Hurst