TITLE:   GCN CIRCULAR
NUMBER:  7182
SUBJECT: optical observations, XRT in NGC 2770
DATE:    08/01/15 13:54:47 GMT
FROM:    Bill Peterson at U of Iowa/Dept Phys Astro  <albedozero@gmail.com>

B. Peterson, T. Jaeger, R. Mutel

Optical observations were made of the transient X-ray source in NGC 2270 (cfr. GCN 
7159) on 11, 12 and 14 Jan. using the 37cm "Rigel" telescope based in southern 
Arizona.  We used GSC 2495:1420 as a reference for differential photometry, 
assigning it a nominal magnitude of 14.3.
We plan further monitoring observations including short photometric scans of 
Tycho-2 stars in the field, allowing true magnitudes of the transient to be 
determined.

unfiltered      SN2007uy        XRT
2008/1/11       15.897 +/-0.005 17.919 +/-0.015
2008/1/12       15.825 +/-0.005 17.934 +/-0.017
2008/1/14       15.779 +/-0.005 18.041 +/-0.019

B filter
2008/1/11       15.989 +/-0.021 <19
2008/1/12       15.984 +/-0.012 18.030 +/-0.045
2008/1/14       15.912 +/-0.014 18.134 +/-0.059

V filter
2008/1/11       15.725 +/-0.010 18.320 +/-0.049
2008/1/12       15.684 +/-0.010 18.407 +/-0.054
2008/1/14       15.577 +/-0.010 18.344 +/-0.062

R filter
2008/1/11       15.830 +/-0.010 17.882 +/-0.034
2008/1/12       15.770 +/-0.010 18.245 +/-0.046