2024/02/01 by Junhui Liu, Jianfeng Wu, Liu, Junhui +1 · 1 citation
Physics and Astronomy · #Astronomy and Astrophysical Research #FOS: Physical sciences #Gamma-ray bursts and supernovae #High Energy Astrophysical Phenomena (astro-ph.HE) #Solar and Stellar Astrophysics (astro-ph.SR) #Stellar, planetary, and galactic studies
paper · pdf · doi:10.48550/arxiv.2402.00640
openalex publication_date 2024/02/01 · openalex created_date 2024/02/03 · openalex updated_date 2026/07/28
X-ray emission is an important tracer of stellar magnetic activity. We carried out a systematic correlation analysis for the X-ray luminosity log L\rm X, bolometric luminosity log L\rm bol, and X-ray activity level log(L_\textrmX/L_\textrmbol) versus the binary parameters including orbital period P, Rossby number R\rm O, effective temperature T\rm eff, metallicity [Fe/H] and the surface gravity log g, and the stellar mass M & radius R, by assembling a large sample of semi-detached (EB-type) binaries with X-ray emission (EBXs). The fact that both log L\rm X and log L\rm bol change in accordance with log P indicates that X-ray emission originates from the convection zone, while log L\rm X is proportional to the convection zone area. We found that EBXs with main-sequence components exhibit an upward and then a downward trend in both the log T\rm eff-log L_\textrmX and M-log L_\textrmX relations, which is different from the monotonically decreasing trend shown by EBXs containing sub-giant and giant components. The magnetic activity level is negatively correlated with log T\rm eff and stellar mass. Based on the magnetic dynamo model, the variations in the size and thickness of the surface convection zones can explain the observed relations. EBXs with main-sequence components have similar R\rm O-log(L_\textrmX/L_\textrmbol) relationship to that of the binaries in the clusters as Praesepe and Hyade. We compared the X-ray radiation properties of EBXs with those of the X-ray-emitting contact binaries and found that EBXs have broader value ranges for log L\rm X and log(L_\textrmX/L_\textrmbol).