Optical follow-up of NGC1275
ATel #7249; Roberto Nesci (INAF/IAPS)
on 18 Mar 2015; 23:02 UT
Credential Certification: Roberto Nesci (Roberto.Nesci@iaps.inaf.it)
Following the alert in ATel #7239 of a bright state in Gamma rays of NGC 1275, I observed the source with the 30cm telescope of the Foligno Observatory (IAU K56) on 2015-03-18.80. Photometry was made with IRAF/apphot using an aperture of 2.3 arcsec to include only the galaxy nucleus. The sky level was measured at 30 arcsec distance, to avoid the galaxy contribution. Comparison stars were taken from Fiorucci, Tosti and Rizzi (1998 PASP 110, 105). The nucleus was easily detected at V=13.80 +/-0.01.
The historic light curve in the R band of NGC 1275 in the Perugia Observatory database (years 1994-2003, Marchili 2002) shows an erratic behaviour without any clear long term trend. Its average value is R=13.45, color index V-R=0.4, and peak to peak amplitude of 0.4 mag.
Our V=13.8 corresponds to R=13.4, that is the average value of the source. We can therefore exclude that the nucleus of NGC 1275 has presently a peculiarly high optical emission.
