@Article{OliveiraLimSteBorCie:2014:OrPeV,
               author = "Oliveira, A. S. and Lima, H. J. F. and Steiner, J. E. and Borges, 
                         B. W. and Cieslinski, Deonisio",
          affiliation = "{Univ Vale Paraiba} and {Univ Vale Paraiba} and {Univ Sao Paulo} 
                         and {Univ Fed Santa Catarina} and {Instituto Nacional de Pesquisas 
                         Espaciais (INPE)}",
                title = "The orbital period of the V Sge star candidate QU Carinae",
              journal = "Monthly Notices of the Royal Astronomical Society",
                 year = "2014",
               volume = "444",
               number = "3",
                pages = "2692--2699",
                month = "Nov.",
             keywords = "binaries: close, stars: individual: QU Car, novae, cataclysmic 
                         variables, supernovae: general, X-rays: binaries.",
             abstract = "Close binary supersoft X-ray sources (CBSS) are considered strong 
                         candidates to Type Ia supernova progenitors, but very few CBSS are 
                         known in our Galaxy. The Galactic counterparts of the CBSS may be 
                         the V Sge stars, not detected in X-rays due to the strong 
                         absorption by the interstellar gas. Nevertheless, the number of 
                         members in the V Sge class is still small. In order to find new 
                         members, we selected QU Car for photometric and spectroscopic 
                         observations. The orbital period of this system was published in 
                         the literature as 10.9 h, determined from radial velocity data 
                         taken in 1979-1980, but posterior analysis of data taken in 
                         2006-2007 did not confirm this period. We analysed the high 
                         variability of its emission line profiles with the temporal 
                         variance spectrum (TVS) technique. Besides, we recovered the 10.9 
                         h orbital period from the radial velocities of the He II 4686 
                         angstrom emission line and, for the first time, detected what may 
                         be the orbital modulation in the photometric data. This 
                         photometric modulation is present only in the lower brightness 
                         state data, when the flickering is attenuated. The inclusion of QU 
                         Car in the V Sge class is supported by many features like high/low 
                         states, strong winds, nebular lines and He II 4686 angstrom/H beta 
                         emission line ratios. However, the non-detection of the 
                         characteristic O VI 3811-34 angstrom lines in its spectrum claims 
                         against this classification. These lines, though, may be highly 
                         variable so additional spectra analysed with the TVS technique 
                         can, possibly, solve this question.",
                  doi = "10.1093/mnras/stu1624",
                  url = "http://dx.doi.org/10.1093/mnras/stu1624",
                 issn = "0035-8711",
                label = "isi 2015-01 OliveiraLimSteBorCie:2014:OrPeV",
             language = "en",
           targetfile = "MNRAS-2014-Oliveira-2692-9.pdf",
        urlaccessdate = "19 abr. 2024"
}