Optical observations of SN 2005cs and the possible X-ray Flash in M51
ATel #561; Avishay Gal-Yam (Caltech)
on 8 Jul 2005; 21:21 UT
Credential Certification: Avishay Gal-Yam (email@example.com)
Subjects: Optical, Supernovae, Transient
Avishay Gal-Yam (Caltech) reports for the CCCP: Preliminary analysis of the U-band light curve of SN 2005cs in M51 (http://www.astro.caltech.edu/~avishay/sn2005cs-LC-U.png), obtained with the Palomar Observatory robotic 60" telescope+CCD camera in the course of the CCCP, shows a monotonic decline of approximately 0.45 mag between July 1 and July 7. Similar behavior is observed also in R-band. In particular, observations obtained around July 6.28 UT, shortly after the X-ray flash from M51 detected by SWIFT (July 6.231 UT; Immler, Kong, & Lewin, CBET #176) are fully consistent with the trend seen in our U-band data from July 1,2,4 and 7. Preliminary analysis of our R-band data using image subtraction does not reveal any additional variable sources within 20" of the SN.