[ Previous | Next ]
ATEL # 1225; A. W. Shafter (SDSU), M. F. Bode, M. J. Darnley (Liverpool JMU), K. A. Misselt (U. Arizona), R. Quimby (Caltech), and F. Yuan (U. Mich.)
on 27 Sep 2007; 18:04 UT
Password Certification: Allen W. Shafter (email@example.com)
Subjects: Optical, Cataclysmic Variables, Nova, Transients
As part of an ongoing study of novae in nearby galaxies, we report optical photometric and spectroscopic observations of the extragalactic nova M33 2007 No. 01 (CBET #1074, CBET #1080). Our spectroscopic observations (4280Å – 7260Å, at ~ 4.5Å resolution), which were obtained on 22 Sep 2007 UT (four days after discovery) with the Marcario Low Resolution Spectrograph on the Hobby-Eberly Telescope, confirm that the nova is a member of the He/N spectroscopic class of Williams (1992). Specifically, the spectrum shows extremely strong and broad [EW (H&alpha) ~ 800Å, FWHM (H&alpha) ~ 5500 km/s] Balmer, N II,III, and He I,II emission lines. Photometric observations obtained with the ROTSE IIIb telescope at McDonald Observatory show that the nova has faded approximately two magnitudes (unfiltered) in the first six days after discovery. Such a rapid fade rate is consistent with that expected for a He/N nova. The observed magnitude at maximum light (~16.5) allows us to place a conservative lower limit on the luminosity of the nova, M < − 8.2, at the distance of M33 (taken to be &mu = 24.7). Given that maximum light could have been missed by up to a day, and that we have not made any correction for extinction, the nova is likely to be somewhat more luminous.
This material is based upon work supported by the National Science Foundation under Grant No. 0607682 (to AWS), and on observations obtained with the Marcario Low Resolution Spectrograph on the Hobby - Eberly Telescope, which is operated by McDonald Observatory on behalf of the University of Texas at Austin, the Pennsylvania State University, Stanford University, the Ludwig-Maximillians-Universitaet, Munich, and the George-August-Universitaet, Goettingen. Public Access time is available on the Hobby-Eberly Telescope through an agreement with the National Science Foundation.