Photometry of SN 2002bo with template image subtraction

VRI photometry of the type Ia supernova 2002bo is presented. This SN exploded in a dusty region of the host galaxy NGC 3190, thus, subtraction of a template frame was necessary to obtain reliable photometry. We used a template frame of NGC 3190 taken during the course of our galaxy imaging project, fortunately, just a few days before SN 2002bo was discovered. The aim of this project is to collect template frames of nearby galaxies that are potential hosts of bright SNe. Subtraction of pre-SN images helped us to exclude the background light contamination of the host galaxy. The maximum occurred at JD 2 452 346, with maximal V brightness of 13.(m)58. MLCS analysis led to T-0(B) = JD 2 452 346.1 +/- 0.8 (fiducial B-maximum), E(B- V); = 0.(m)24 +/- 0.(m)02, mu(0) = 32.46 +/- 0.06, Delta = - 0.14 +/- 0.04. E(B- V) = 0.(m)24(2) indicates a significant extinction in the host galaxy as the galactic reddening is negligible toward NGC 3190. The accepted value of Delta indicates that SN 2002bo was a slightly overluminous SN by about 0.(m)14 relative to fiducial SN type Ia. The distance turned out to be 31.0 +/- 3 Mpc. In addition, the heavily obscured SN 2002cv was also detected on the I frame taken on JD 2 452 434 ( June 8, 2002), and a variable star is found in the field, very close to the host galaxy.