Abstract Details
| Name: Mami Deka Affiliation: Cotton University Conference ID: ASI2024_376 Title : The impact of convection and metallicity on instability strip boundaries of Classical Cepheids Authors and Co-Authors : Mami Deka1, Earl P. Bellinger2,3,4, Shashi M. Kanbur5, Sukanta Deb1,6, Anupam Bhardwaj7, Hugh Riley Randall5, Selim Kalici5, Susmita Das8 Abstract Type : Oral Abstract Category : Stars, Interstellar Medium, and Astrochemistry in Milky Way Abstract : Classical Cepheid, one type of pulsating variable is vital for measuring cosmic distances thanks to their period-luminosity (PL) relation and contributes to the ongoing debate surrounding the "Hubble constant". The instability strip (IS) is the home to the classically pulsating stars such as Classical Cepheids, Type II Cepheids, RR-Lyraes, δ-Scuti stars. The slope and intercept of PL relation are strongly coupled with the slope and intercept of IS edges (Simon & Young, 1997). A steeper/shallower instability region implies a steeper/shallower PL relation for a certain stellar population. Analysis of IS will provide us with new insights into the properties of Cepheids and thereby contribute to improving the PL relation. However, the internal structure of the IS is still unclear. What is the exact physical condition that determines the required depth of the He II region that makes these stars variable while entering the IS through the blue/hot edge? What is the other physical mechanism that is making these stars again steady while leaving the IS through the red/cool edge? How these physical processes are influenced by metallicity, temperature, mass, etc.? I intend to present our recent findings on this topic, both from observational and theoretical perspectives. |