TITLE:   GCN CIRCULAR
NUMBER:  7186
SUBJECT: NGC 2770B has the same redshift as NGC 2770
DATE:    08/01/15 22:42:35 GMT
FROM:    Daniele Malesani at Niels Bohr Inst,Dark Cosmology Center  <malesani@astro.ku.dk>

Johan P.U. Fynbo, Daniele Malesani (DARK), Thomas Augusteijn, and 
Sami-Matias Niemi (NOT), report:

We acquired a spectrum of the galaxy (or galaxy pair) NGC 2770B, located 
~3 arcmin West of NGC 2770, the host galaxy of XRF 080109 / SN 2008D 
(Berger & Soderberg, ATel 1353; Deng & Zhu, GCN 7160). Observations were 
carried out with the Nordic Optical Telescope, starting on 2007 Jan 
15.213 UT, for a total exposure time of 10 min.

 From the detection of prominent nebular lines, including Balmer 
features, [OII], [OIII], [SII], [NII] and others, we determine the 
redshift to be z = 0.0064 +- 0.0003. This is very similar to the 
redshift of NGC 2770 (z=0.0065 according to NED). At the corresponding 
distance (25.7 Mpc), the angular separation of ~3 arcmin corresponds to 
only 22 kpc in projection.

Similarly to NGC 2770, NGC 2770B is undergoing intense star formation, 
as implied by its blue colors and the large Halpha equivalent width. 
Although there is not much evidence for morphological distorsions, a 
past interaction might have triggered the strong starburst activity in 
both objects.