Supernova in NGC 7678

by Alain Klotz

1. Instrumental design

I observed about 300 galaxies by clear night since 1 feb 2000 with a fully automatized LX200 telescope (8" diameter). The CCD is an Audine equiped by an Kaf-401E chip (grade 0 quality). The camera has no shutter. An "unsmearing" algorithm is used after the dark correction. The flat correction is not performed. Each image is integrated 60 seconds with a binning 2x2 (sampling is 3.6 arcsec/pixel). About 300 to 400 fields are recorded each night. A quick visu software, named SNVisu, was created with the AudeLA platform. It allows to see the night image (at left) and the reference image (at right) on the same screen.

2. Images

The screen copy below indicate the DATE-OBS of the images (UT). North is up and East is left (no inversion).
Candidate : 2002-06-18T02:09:21.30
Reference : 2001-09-11T22:29:14.20

The supernova is located at about 22" N, 30" E from the nucleus of the galaxy. The magnitude is estimated to 15.1. A stack of 8 images of 60s, corrected by dark and flat, taken on 2002-06-19T00:26:09.02 (through haze !) shows the new star agin :

Bellow, the DSS image. A faint HII region appears near the SN position :