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ATEL # 1186; E. Barsukova, N. Borisov, S. Fabrika, O. Sholukhova, A. Valeev (Special Astrophysical Observatory, Russia), V. Goranskij (SAI, Moscow Univ.), V. Burwitz (Max-Planck-Institute fuer extraterrestrische Physik, MPE), W. Pietsch (MPE), D. Hatzidimitriou (Department of Physics, University of Crete, UoC)
on 20 Aug 2007; 16:20 UT
Password Certification: Barsukova E.A. (email@example.com)
Subjects: Optical, Nova, Variables, Stars
We performed spectroscopy of four optical nova candidates in M31 using the Russian 6-m telescope and the SCORPIO spectrograph. The spectral range was 380-755 nm, and the spectral resolution was 1.34 nm.
M31N 2007-07b (E. Ovcharov, et al., ATel#1139):
The exposure was taken between 2007 July 19.925 and 19.957 UT about 10 days after the discovery. Balmer emission lines are dominant. The value of FWHM(Halpha) corrected for instrumental profile and EW(Halpha) are 1600 km/s and -71 nm, correspondingly. Numerous FeII emission lines are seen. NaI D doublet and forbidden [OI] lines at 557.7, 630.0 and 636.4 nm are present. The object most likely is a FeII class nova.
M31N 2007-07c (V. Burwitz et al., ATel#1146):
The exposure was taken between 2007 Aug. 11.007 and 11.012 UT about 23 days after the discovery. The spectrum has undergone radical changes since July 21 (ATel#1152). Balmer emission lines are now very strong. FWHM(Halpha) = 2400 km/s. EW(Halpha) = -460 nm. Three HeI emission lines are surely identified at 587.6, 667.8 and 706.5 nm. FeII emission lines evidently exist. The object most likely is a hybrid or He/N class nova.
M31N 2007-07e (D. Hatzidimitriou, et al, ATel#1156):
The exposure was taken between 2007 Aug. 8.972 and Aug. 9.002 UT about 13 days after the discovery. There are strong Balmer emission lines. FWHM(Halpha) = 1630 km/s and EW(Halpha) = -71 nm are very close to those of nova M31N 2007-07b. We identified also strong and numerous FeII lines and the NaI D doublet in emission. The object most likely is a FeII class nova.
TSS J004054.4+405350 (R. Quimby et al., ATel#1173):
The exposure was taken between 2007 Aug. 10.977 and 10.999 UT about 5 days after the discovery. Strong Balmer emission lines are seen. FWHM(Halpha) = 1880 km/s. EW(Halpha) = -66 nm. FeII emission lines are moderately strong. The emission blend at 588 nm probably consists of HeI 587.6 nm and NaI D lines. HeI emission is present also at 667.8 and 706.5 nm. Three forbidden [OI] lines are identified, and emission at 567.8 nm is a probable NII blend. The object is a FeII class or a hybrid nova.