| Abstract | New photometry is presented for a group of sinusoidal cepheids in the Large Magellanic Cloud. Although they appear to mix well with normal cepheids in the instability strip they form a unique, parallel, period-luminosity relation to that of normal cepheids. Excellent agreement is found with theoretical fundamental and first-overtone blue edges indicating that the sinusoidal cepheids are pulsating in their first-overtone. This agreement with the blue edges is only valid for an LMC distance modulus of 18.56. The sinusoidal cepheids in the LMC have the same luminosity as the Galactic double-mode cepheids. The reason for this is not understood. |
