A theoretical framework for BL Her stars III. A case study: Robust light curve optimisation in the LMC

Abstract

We carry out an extensive light curve comparison of BL Her stars using observations from Gaia DR3 and stellar pulsation models computed using MESA-RSP with the goal to obtain the best-matched modeled-observed pairs for BL Her stars in the LMC. We use the Fourier decomposition technique to analyse the light curves in the G band obtained from Gaia DR3 and from MESA-RSP and use a robust light curve fitting approach to score the modeled-observed pairs with respect to their pulsation periods and over their Fourier parameter space. We obtain the best-fit models for 48 BL Her stars in the LMC and thereby provide the stellar parameter estimates of these stars, 30 of which are labelled as the gold sample with superior light curve fits. We find a relatively flat distribution of stellar masses between 0.5-0.65 Msolar for the gold sample of modeled-observed pairs. An interesting result is that the majority of the best-matched models in the gold sample are computed using the convection parameter sets without radiative cooling. The period-Wesenheit relation for the best-matched gold sample of 30 BL Her models exhibits a slope of $-2.805\pm 0.164$ while the corresponding period-radius relation exhibits a slope of $0.565\pm 0.035$, both in good agreement with the empirical PW and PR slopes from BL Her stars in the LMC, respectively. We also used the Wesenheit magnitudes of the 30 best-matched modeled-observed pairs to estimate a distance modulus of ${\mu }_{\mathrm{LMC}}=18.582\pm 0.067$ to the LMC, which lies within the bounds of previous literature values. We also discuss the degeneracy in the stellar parameters of the BL Her models that result in similar pulsation periods and light curve structure, and highlight that caution must be exercised while using the stellar parameter estimates.

20 pages, 10 main text figures, 5 appendix figures, 1 main text table, 1 appendix table. Accepted for publication in Astronomy & Astrophysics

References in corpus (59)

• The chemical composition of the Sun
• The Gaia mission
• Nine-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Cosmological Parameter Results
• Modules for Experiments in Stellar Astrophysics (MESA)
• Gaia Data Release 3: Summary of the content and survey properties
• Modules for Experiments in Stellar Astrophysics (MESA): Giant Planets, Oscillations, Rotation, and Massive Stars
• Modules for Experiments in Stellar Astrophysics (MESA): Binaries, Pulsations, and Explosions
• Modules for Experiments in Stellar Astrophysics (MESA): Convective Boundaries, Element Diffusion, and Massive Star Explosions
• Modules for Experiments in Stellar Astrophysics (MESA): Pulsating Variable Stars, Rotation, Convective Boundaries, and Energy Conservation
• A Quantitative Comparison of SMC, LMC, and Milky Way UV to NIR Extinction Curves
• A distance to the Large Magellanic Cloud that is precise to one per cent
• Modules for Experiments in Stellar Astrophysics (MESA): Time-Dependent Convection, Energy Conservation, Automatic Differentiation, and Infrastructure
• New Period-Luminosity and Period-Color Relations of Classical Cepheids: I. Cepheids in the Galaxy
• Bump Cepheids in the Magellanic Clouds: Metallicities, the Distances to the LMC and SMC, and the Pulsation-Evolution Mass Discrepancy
• Metal Abundances, Radial Velocities and other Physical Characteristics for the RR Lyrae Stars in the Kepler Field
• OGLE-ing the Magellanic System: Optical Reddening Maps of the Large and Small Magellanic Cloud from Red Clump Stars
• A re-classification of Cepheids in the Gaia Data Release 2
• The Carnegie-Chicago Hubble Program. I. An Independent Approach to the Extragalactic Distance Scale Using only Population II Distance Indicators
• RR Lyrae stars in Galactic globular clusters.III. Pulsational predictions for metal content Z=0.0001 to Z=0.006
• The period-luminosity relation for type II Cepheids in globular clusters
• Gaia DR3: Specific processing and validation of all-sky RR Lyrae and Cepheid stars -- The Cepheid sample
• Theoretical models for Bump Cepheids
• Light curve analysis of Variable stars using Fourier decomposition and Principal component analysis
• Period doubling bifurcation and high-order resonances in RR Lyrae hydrodynamical models
• Classical Cepheid Pulsation Models. XI. Effects of convection and chemical composition on the Period-Luminosity and Period-Wesenheit relations
• The Eclipsing Binary Cepheid OGLE-LMC-CEP-0227 in the Large Magellanic Cloud: pulsation modelling of light and radial velocity curves
• Period-luminosity relations of type II Cepheids in the Magellanic Clouds
• Large Magellanic Cloud Bump Cepheids: Probing the Stellar Mass-Luminosity Relation
• Discovery of period doubling in BL Herculis stars of the OGLE survey. Observations and theoretical models
• Pulsation models for the 0.26M_sun star mimicking RR Lyrae pulsator. Model survey for the new class of variable stars
• Period-Luminosity Relations for Type II Cepheids and their Application
• Nonlinear asteroseismology of RR Lyrae
• The period-luminosity and period-radius relations of Type II and anomalous Cepheids
• Survey of non-linear hydrodynamic models of type-II Cepheids
• The Mid-Infrared Extinction Law in the Large Magellanic Cloud
• Synthetic properties of bright metal-poor variables. II. BL Her stars
• A "pulsational" distance determination for the Large Magellanic Cloud
• The VMC survey - XXIII. Model fitting of light and radial velocity curves of Small Magellanic Cloud classical Cepheids
• The Ages of Galactic Bulge Stars with Realistic Uncertainties
• A Comparative Study of Multiwavelength Theoretical and Observed Light Curves of Cepheid Variables
• Galactic Bulge Population II Cepheids in the VVV Survey: Period-Luminosity Relations and a Distance to the Galactic Center
• Theoretical fit of Cepheid light an radial velocity curves in the Large Magellanic Cloud cluster NGC 1866
• Evolutionary and pulsation properties of Type II Cepheids
• Period doubling and Blazhko modulation in BL Herculis hydrodynamic models
• When a Period Is Not a Full Stop: Light Curve Structure Reveals Fundamental Parameters of Cepheid and RR Lyrae Stars
• On the separation between RR Lyrae and Type II Cepheids and their importance for distance determination: the case of $\omega$ Cen
• Updated pulsation models for BL Herculis stars
• A theoretical framework of BL Her stars. I. Effect of metallicity and convection parameters on period-luminosity and period-radius relations
• The Optical to Infrared Extinction Law of Magellanic Clouds Based on Red Supergiant and Classical Cepheid
• On the variation of light curve parameters of RR Lyrae variables at multiple wavelengths
• An absolute calibration of the near-infrared Period-Luminosity Relations of Type II Cepheids in the Milky Way and in the Large Magellanic Cloud
• Zwicky Transient Facility and Globular Clusters: The Period-Luminosity and Period-Wesenheit Relations for Type II Cepheids
• Calibration of the convective parameters in stellar pulsation hydrocodes
• The stellar photosphere-hydrogen ionization front interaction in Classical Pulsators: a theoretical explanation for observed period-colour relations
• Anomalous RR Lyrae stars(?). III. CM Leonis
• Chaos in hydrodynamic BL Herculis models
• Near-infrared observations of RR Lyrae and Type II Cepheid variables in the metal-rich bulge globular cluster NGC 6441
• Temperature dependent convective parameters for RRc 1D-models
• Multi-wavelength Photometric Study of RR Lyrae Variables in the Globular Cluster NGC 5272 (Messier 3)

Cited by in corpus (3)

• The light curve model fitting of LMC Cepheids: MESA-RSP versus Stellingwerf's code predictions
• A theoretical framework for BL Her stars IV. New period-luminosity relations in the Rubin-LSST filters
• Matching seismic masses for RR Lyrae-type and oscillating red horizontal-branch stars in M4