Abstract Details

Name: Susmita Das
Affiliation: University of Delhi
Conference ID: ASI2021_325
Title : Period-luminosity and period-radius relations for MESA-computed BL Her models
Authors and Co-Authors : Susmita Das (University of Delhi, India), Shashi M. Kanbur (State University of New York Oswego, USA), Radoslaw Smolec (Nicolaus Copernicus Astronomical Center of the Polish Academy of Sciences, Poland), Anupam Bhardwaj (Korea Astronomy and Space Science Institute, Republic of Korea), Harinder P. Singh (University of Delhi, India) and Marina Rejkuba (European Southern Observatory, Germany)
Abstract Type : Oral
Abstract Category : Stars, ISM and Galaxy
Abstract : We present new multiwavelength (UBVRI JHKLL′M) period-luminosity (PL) and period-radius (PR) relations for a fine grid of convective BL Herculis models computed using the non-linear radial stellar pulsation tool MESA-RSP. The non-linear models were computed for periods typical for BL Her stars, i.e. 1 ≤ P(days) ≤ 4 covering a wide range of input parameters - metallicity (−2.0 dex ≤ [Fe/H] ≤ 0.0 dex), stellar mass (0.5M⊙ -0.8M⊙), luminosity (50L⊙ -300L⊙ ) and effective temperature (full extent of the instability strip; in steps of 50K). We study the effect of metallicity and four sets of different convection parameters on the PL and PR relations at mean light. The theoretical PL and PR relations obtained using our computed BL Her models match well with empirical relations. However, PL slopes of the models with radiative cooling provide a better match to empirical relations for BL Her stars in the LMC in the HK bands. For each set of convection parameters, the effect of metallicity is negligible in infrared bands, consistent with empirical results. No significant metallicity effects are seen in the PR relations.