Photometric properties and stellar parameters of the rapidly rotating magnetic early-B star HD 345439

TL;DR

This study characterizes the magnetic, rotational, and stellar parameters of the early-B star HD 345439 through multicolor photometry, spectral analysis, and modeling, revealing its rotation period, magnetic obliquity, and fundamental stellar properties.

Contribution

It provides the first detailed photometric and stellar parameter analysis of HD 345439, including its rotation period, magnetic geometry, and physical characteristics, using multi-method observations and modeling.

Findings

Rotation period of 0.7699 days identified.

Magnetic obliquity and inclination angles constrained.

Stellar parameters such as temperature, mass, and age estimated.

Abstract

We first present the multicolor photometry results of the rapidly rotating magnetic star HD 345439 using the Nanshan One-meter Wide-field Telescope. From the photometric observations, we derive a rotational period of 0.7699\pm0.0014 day. The light curves of HD 345439 are dominated by the double asymmetric S-wave feature that arises from the magnetic clouds. Pulsating behaviors are not observed in Sector 41 of the Transiting Exoplanet Survey Satellite. No evidence is found of the occurrence of centrifugal breakout events neither in the residual flux nor in the systematic variations at the extremum of the light curve. Based on the hypothesis of the Rigidly Rotating Magnetosphere model, we restrict the magnetic obliquity angle {$\beta$} and the rotational inclination angle $i$ so that they satisfy the approximate relation {$\beta + i \approx 105^{\circ}$}. The colour excess, extinction, and luminosity are determined to be $E_{(B-V)}=0.745\pm0.016\,$mag, $A_{V}=2.31\pm0.05\,$mag, and $\rm log\,(L/L_{\odot})=3.82\pm0.1 $dex, respectively. Furthermore, we derive the effective temperature as $T$$\rm _{eff}=22\pm1 $kK and the surface gravity as log$g=4.00\pm0.22$. The mass$ M=7.24_{-1.24}^{+1.75}\rm M_{\odot}$, radius$ R=4.44_{-1.93}^{+2.68}\rm R_{\odot}$, and age$\rm \tau_{age}=23.62\,_{-21.97}^{+4.24} $Myr are estimated from the Hertzsprung--Russell Diagram