An extension of a geometric method for finding cepheid distances.
Abstract
The method of Barnes et al. (1977) for finding the distance to a Cepheid by a surfacebrightness technique requires a radialvelocity curve. An attempt is made to show how this requirement can be eliminated by expressing the total linear amplitude of pulsation solely in terms of the product of period and light amplitude. Revised pulsation amplitudes expressed in astronomical units are derived for 13 Cepheids and equated to the angular amplitudes given by the surfacebrightness technique. The distances to nine Cepheids are then obtained and shown to be as accurate as those determined by Barnes et al. through integration of available velocity curves. The possibility is noted that the proposed method might even be applicable to brighter extragalactic Cepheids if sufficient care is taken with photometry.
 Publication:

Monthly Notices of the Royal Astronomical Society
 Pub Date:
 August 1977
 DOI:
 10.1093/mnras/180.3.339
 Bibcode:
 1977MNRAS.180..339F
 Keywords:

 Cepheid Variables;
 Distance;
 Stellar Luminosity;
 Stellar Spectrophotometry;
 Astrometry;
 Light Curve;
 Radial Velocity;
 Regression Analysis;
 Stellar Radiation;
 Astronomy