2010CBET.2136....1H

Further to CBET 2127, K. Hornoch, Astronomical Institute, Ondrejov; J. Prieto, Carnegie Observatories; and R. Khan and O. Pejcha, Department of Astronomy, Ohio State University, report additional low-resolution optical spectroscopy (range 400-750 nm, resolution 1.4 nm) and optical photometry of M31N 2010-01a. Spectra were obtained using the Boller & Chivens CCD Spectrograph on the 2.4-m Hiltner telescope at MDM Observatory; a spectrogram of M31N 2010-01a, taken by Prieto and Khan on 2010 Jan. 15.09 UT (3.96 days after its first optical detection made by V. Burwitz et al.) shows evolution with respect to their previous observation — namely, the P-Cyg profiles disappeared and the spectrum is dominated by strong emission lines of the Balmer series up to at least H-epsilon, and emission lines of iron. The object is thus confirmed as an "Fe II"-class nova in its early decline phase. The HWZI of H-alpha and H-beta is about 2500 km/s. Magnitude measurements were obtained from images taken with RETROCAM on the 2.4-m Hiltner telescope; additional Sloan magnitudes for M31N 2010-01a measured by Hornoch from 2.4-m telescope images taken by Prieto and Khan: Jan. 14.082, g' = 16.71 ± 0.09; 14.087, r' = 16.54 ± 0.03; 15.096, g' = 16.99 ± 0.10; 15.100, r' = 16.86 ± 0.04.