BE Ursae Majoris /PG 1155 + 492/ - A unique cataclysmic-variable-like object

Abstract

view Abstract Citations (37) References (21) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS BE UMa (PG 1155+492) : a unique cataclysmic-variable-like object. Ferguson, D. H. ; Liebert, J. ; Green, R. F. ; McGraw, J. T. ; Spinrad, H. Abstract The variable spectrum of BE Ursae Majoris, which is similar to that of the cataclysmic variables (CVs), shows (1) an emission-line spectrum with the high-excitation CN 4650 A blend as the strongest optical feature, weaker H and He lines, and a strong Balmer jump, and (2) an absorption spectrum dominated by He. Although the object shows no evidence of photometric variability on either short or long time-scales, it has been shown by Kurochkin (1964, 1971) to have a 2.29-day, sinusoidal, 1.5-mag variation. The luminosity is dominated by a UV power-law component, though the 4000-10000 A continuum is flat. The hypothesis that this object is an active mass transfer binary is not supported by its photometric behavior, energy distribution and long period, despite the spectroscopic variability. Nevertheless, three components whose nature is not understood remain: (1) an ultraviolet source whose energy distribution is explainable neither by a uniform temperature primary star nor by an accretion disk; (2) a reprocessed component powered by the UV star; and (3) a component similar to a CV disk, producing the optically thick Balmer lines. Publication: The Astrophysical Journal Pub Date: December 1981 DOI: 10.1086/159455 Bibcode: 1981ApJ...251..205F Keywords: Balmer Series; Binary Stars; Dwarf Stars; Novae; Stellar Luminosity; Stellar Spectra; Absorption Spectra; Emission Spectra; Spectrum Analysis; Stellar Spectrophotometry; Ultraviolet Spectra; Variable Stars; Astronomy full text sources ADS | data products SIMBAD (2) MAST (1)