Oral Presentation

Distance Scale and Variable Stars Research at National Central University

Chow-Choong Ngeow (National Central University)

Cosmic distance scale ladder utilizes pulsating stars, such as classical Cepheids and RR Lyrae, in the local universe to calibrate secondary distance indicators (such as type Ia supernova and Tully-Fisher relation), with ultimate goal of determining Hubble constant within few percent level. In this talk, I review some of the recent work in distance scale and variable stars carried out at National Central University. These include: (a) Cepheids period-luminosity in the mid infrared; (b) Search of ultra-long period Cepheids in M31 using PTF data; (c) Multi-color follow-up observations of RR Lyrae stars in Kepler fields; and (d) Recent results of variable stars search using TAOS-I data. A number of meter-class and small aperture telescopes in Taiwan, Korea and USA (mainly in California and Arizona) have been involved in (b), (c) and (d), which demonstrate the power of these telescopes in time domain and variable stars research.