TITLE: GCN CIRCULAR NUMBER: 8210 SUBJECT: GRB 080905B: Photometric Redshift for the 2MASS Galaxy DATE: 08/09/10 13:45:38 GMT FROM: Stephen Holland at USRA/NASA/GSFC/SSC Stephen Holland (CRESST/USRA/GSFC) reports, on behalf of the Swift/UVOT team: We have performed UVOT photometry on the 2MASS galaxy 2MASX J20065732-6233465 galaxy located 4 arcsec from the optical afterglow of GRB 080905B (Stroh et al., 2008, GCNC 8182). Our magnitudes are: Filter Mag Err v 17.85 0.05 b 18.70 0.05 u 18.46 0.05 uvw1 18.76 0.07 uvm2 18.71 0.07 uvw2 18.76 0.07 These magnitudes are not corrected for the Galactic extinction corresponding to a reddening of E_{B-V} = 0.05 mag (Schlegel et al., 1998, ApJS, 500, 525) along this line of sight. The photometry is on the UVOT photometric system described in Poole et al. (2008, MNRAS, 383,627). The detection in the uvw2 filter implies that the redshift of the 2MASS galaxy can not be greater than approximately z = 1.7. This is inconsistent with the VLT redshift of z = 2.374 for the afterglow (Vreeswijk, et al., 2008, GCNC 8191). This suggests that the 2MASS galaxy is not the host galaxy of GRB 080905B.