2020/10/13 by Susmita Das, Das, Susmita, Shashi M. Kanbur +7
Physics and Astronomy · #Stellar, planetary, and galactic studies #Astronomy and Astrophysical Research #Scientific Research and Discoveries
paper · pdf · doi:10.48550/arxiv.2010.06624
Period-color (PC) relations may be used to study the interaction of the\nstellar photosphere and the hydrogen ionization front (HIF). RR Lyraes (RRLs)\nand long period classical Cepheids (P > 10d) have been found to exhibit\ndifferent PC behavior at minimum and maximum light which can be explained by\nthe HIF-photosphere interaction based on their location on the HR diagram. In\nthis work, we extend the study to include type II Cepheids (T2Cs) with an aim\nto test the HIF-photosphere interaction theory across a broad spectrum of\nvariable star types. We find W Vir stars and BL Her stars to have similar PC\nrelations as those from long period and short period classical Cepheids,\nrespectively. We also use MESA to compute RRL, BL Her and classical Cepheid\nmodels to study the theoretical HIF-photosphere distance and find the results\nto be fairly consistent with the HIF-photosphere interaction theory.\n