Abstract
view Abstract Citations (37) References (31) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The mass of the anomalous cepheid in the globular cluster NGC 5466. Zinn, R. ; King, C. R. Abstract The effective temperature and surface gravity of the anomalous Cepheid V19 in NGC 5466 have been measured from spectrophotometric scans. The position of V19 in the θe -log g diagram rules out the possibilities that it is an RR Lyrae or a BL Herculis variable, which strengthens the already strong case that V19 is an unusual Cepheid variable and a member of NGC 5466. It had been shown earlier by Zinn and Dalin that V19 has the same radial velocity as NGC 5466 and a period (0.82 days) and luminosity (Mυ = -1.27) that are similar to those of the anomalous Cepheids in the dwarf spheroidal galaxies. Our observations of V19 have been compared with similar ones of three horizontal branch (HB) stars in NGC 5466 and the type c RR Lyrae variable TV Boo. The following mass ratios are obtained: M(V19)/(HB) = 1.64±0.76 and M(V19)/M(TV Boo) = 2.03±0.62. The surface gravity measurements indicate that V19 is pulsating in the first harmonic rather than the fundamental mode. Assuming the first harmonic mode for V19 and TV Boo, the Q = P<ρ>l/2 relation yields: M1(V19)/(TV Boo) = 2.33 ± 0.40. Thus, it appears that V19 is approximately twice as massive as HB stars. The Q = P<ρ>l/2 relation yields the most precise estimate for V19's mass, l.56+0.23-0.03 Msun, which is consistent with the theory that the large masses of the anomalous Cepheids result from the transfer of mass in close binary systems. Publication: The Astrophysical Journal Pub Date: November 1982 DOI: 10.1086/160462 Bibcode: 1982ApJ...262..700Z Keywords: Cepheid Variables; Globular Clusters; Stellar Mass; Stellar Oscillations; Variable Stars; Giant Stars; Horizontal Branch Stars; Stellar Gravitation; Stellar Temperature; Astrophysics full text sources ADS | data products SIMBAD (5)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
