Abstract Details

Name: Bharti Arora
Affiliation: ARIES, Nainital
Conference ID: ASI2020_374
Title : X-ray study of a deeply embedded Wolf-Rayet star WR 121a
Authors and Co-Authors : Bharti Arora
Abstract Type : Oral
Abstract Category : Stars, ISM and Galaxy
Abstract : An X-ray study of a deeply embedded Wolf-Rayet star WR 121a have been carried out using archival observations from Chandra and XMM-Newton. The periodic variations have been seen in the X-ray light curves of WR 121a corresponding to a period of 4.110 ± 0.001 days. The X-ray spectrum of WR 121a has been well-explained by a thermal plasma emission model with temperatures of 0.98 ± 0.34 keV and 3.55 ± 0.69 keV for the cool and hot components, respectively. The abundances are found to be non-solar. Present study indicates that X-rays are mainly produced because of an active wind collision in WR 121a and it is one of the X-ray bright massive binaries with an X-ray luminosity of ∼10^34 erg s−1. The phase locked modulations have been clearly seen in the flux variation of WR 121a where the flux increased by a factor of ∼1.7 in 0.3-10.0 keV energy band from minimum to maximum. These variations could be caused by an eclipse of the wind collision region by the secondary star in a nearly circular binary orbit. The winds of both the components of WR 121a are suspected to be radiative during all the times and processes like radiative inhibition as well as braking are most likely affecting the wind collision severely in this short period massive binary system.