1997/09/03 by The MACHO Collaboration, C. Alcock, R. A. Allsman +36
Earth and Planetary Sciences · Engineering · Physics and Astronomy · #Astrophysics (astro-ph) #FOS: Physical sciences #Geophysics and Gravity Measurements #Inertial Sensor and Navigation #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/9709025
15 pages, 4 Encapsulated PostScript figures. Submitted to the Astronomical Journal
arxiv created 1997/09/03 · openalex publication_date 1997/09/03 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We report the discovery of 20 1H/2H and 7 F/1H beat Cepheids in the SMC by the MACHO Project. We utilize the 20 1H/2H stars to determine lightcurve shape for the SMC second-overtone (2H) mode of Cepheid pulsation. We predict, similar to the findings of Alcock et al. (1997, ApJ, submitted), that 2H Cepheids will have nearly or purely sinusoidal light variations; that the P-L relation for 2H Cepheids will not be distinguishable from the P-L relation for 1H Cepheids within photometric accuracy; and that 2H stars may be discernable from F and 1H stars using the amplitude-period diagram and Fourier parameter progressions for periods P < 0.7 days, our current sample 2H period limit.