view Abstract Citations (10) References (20) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Chromospherically active stars. I. HD 136905. Fekel, F. C. ; Hall, D. S. ; Africano, J. L. ; Gillies, K. ; Quigley, R. ; Fried, R. E. Abstract The variable star HD 136905, recently designated GX Librae, is a chromospherically active K1 III single-lined spectroscopic binary with a period of 11.1345 days. It has moderate strength Ca II H and K and ultraviolet emission features, while Hα is strongly in absorption. The inclination of the systems is 58°±17° and the unseen secondary is most likely a G or K dwarf. The v sin i of the primary, 32±2 km s-1, results in a minimum radius of 7.0±0.4 R_sun;. Since the star fills a substantial fraction of its Roche lobe, the double-peaked light curve seen by photometric observers is predominantly ellipsoidal in nature. Both the photometry and the spectroscopy yield values for the period and the time of conjunction that are identical within their uncertainties. Publication: The Astronomical Journal Pub Date: December 1985 DOI: 10.1086/113963 Bibcode: 1985AJ.....90.2581F Keywords: Binary Stars; Chromosphere; Stellar Orbits; Ultraviolet Spectra; Variable Stars; Astronomical Photometry; Astronomical Spectroscopy; K Stars; Late Stars; Light Curve; Stellar Atmospheres; Astrophysics full text sources ADS | data products SIMBAD (3) MAST (1) Related Materials (25) Part 2: 1986AJ.....92.1150F Part 3: 1987AJ.....94..726F Part 4: 1988AJ.....95..215F Part 5: 1988AJ.....96.1426F Part 6: 1989AJ.....97..202F Part 7: 1989AJ.....97.1139F Part 8: 1991AJ....101.1489F Part 9: 1991AJ....102.1439F Part 10: 1993AJ....105.2265F Part 11: 1993AJ....106.2370F Part 12: 1994AJ....108..694F Part 13: 1994AJ....108.1936F Part 14: 1995AJ....109.2821F Part 15: 1996AJ....112..269F Part 16: 1997AJ....114.2747F Part 17: 1998AJ....115.1153F Part 18: 2000AJ....120.3265F Part 19: 2001AJ....122..991F Part 20: 2001AJ....122.3447F Part 21: 2002AJ....124.1064F Part 22: 2004AJ....127.2303F Part 23: 2004AJ....127.2931F Part 24: 2005AJ....129.1669F Part 25: 2005AJ....130..794F Part 26: 2007AJ....134.2079F