| Name: | Kerdaris Kurbah |
| Affiliation: | Cotton University |
| Conference ID : | ASI2024_612 |
| Title : | Study of theoretical and observed light curves of First Overtone Cepheids in the Magellanic Clouds |
| Authors : | Kerdaris Kurbah1, Shashi M. Kanbur2, Sukanta Deb1 |
| Authors Affiliation: | 1 Department of Physics, Cotton University, Guwahati 781001, Assam, India
2 Department of Physics, State University of New York, Oswego, NY 23126, USA |
| Mode of Presentation: | Oral |
| Abstract Category : | Galaxies and Cosmology |
| Abstract : | We carried out an analysis of the theoretical and observed light curves of the First Overtone classical Cepheids (FO Cepheids) in the Magellanic Clouds. The observed light curves are taken from the OGLE-IV database, available in (V, I)-bands for both the Large Magellanic Cloud (LMC) and Small Magellanic Cloud (SMC). Theoretical light curves in (V, I)-bands are obtained using state-of-the-art 1D non-linear radial stellar pulsation (RSP) code in MESA (MESA-RSP), for chemical compositions: Z = 0.008 and Z = 0.004, appropriate for the LMC and SMC, respectively. It has been found that period-amplitude (PA) relations for FO Cepheids in the LMC and SMC exhibit different behaviour. The FO Cepheids in the SMC are found to have higher amplitudes compared to the LMC counterparts. Amplitudes of the FO Cepheids in the LMC display a bimodal distribution representing the lower and higher amplitude which can be modelled using a Gaussian Mixture Model whereas the FO Cepheids in the SMC display a one distribution. FO Cepheids in the LMC are found to exhibit sloped/flat relations PC relations at maximum/minimum light and the FO Cepheid in the SMC are found to display sloped PC relation at both maximum and minimum light. This behaviour of the observed/theoretical PC relations of the FO Cepheids support the HIF-photosphere interaction theory. The analysis shows that the FO Cepheids in the LMC and SMC shows different behaviour which may be to their evolutionary history and the different locations of the instability strip in the LMC and SMC. |
