Abstract Details

Name: Barnali Das
Affiliation: NCRA-TIFR, Pune
Conference ID: ASI2019_333
Title : HD 142990: The third main-sequence magnetic star with coherent emission
Authors and Co-Authors : Barnali Das, Poonam Chandra, Gregg A. Wade, M. E. Shultz
Abstract Type : Poster
Abstract Category : Stars, ISM and Galaxy
Abstract : Until last year, CU Vir was the only known main-sequence magnetic star to show periodic pulses which are of coherent nature. Our discovery of the second such star HD 133880 ruled out the possibility that this phenomenon is unique to CU Vir. Note that the observation of coherent emission can help us in constraining certain physical parameters like the stellar rotation period and hence such observations are quite useful. Recently, Lenc. et al. (2018) discovered another star, HD 142990, that show characteristics of coherent emission at 200 MHz. We have observed this star at 610 MHz with the Giant Metrewave Radio Telescope (GMRT) and confirmed that this star indeed has coherent emission mechanism in play. In my talk, I will describe the discovery of this third star and the role of our observation in that. I will also discuss how our observations point out towards some of the shortcomings of the current model of coherent emission from hot magnetic stars.