Imaging studies with the Very Large Array(VLA) have revealed H I emission associated with the extended circumstellar shells of red giants. We analyze the spectral map obtained on Y CVn, a J-type carbon star on the A...Imaging studies with the Very Large Array(VLA) have revealed H I emission associated with the extended circumstellar shells of red giants. We analyze the spectral map obtained on Y CVn, a J-type carbon star on the Asymptotic Giant Branch. The H I line profiles can be interpreted with a model of a detached shell resulting from the interaction of a stellar outflow with the local interstellar medium.We reproduce the spectral map by introducing a distortion along a direction corresponding to the star's motion in space. We then use this fitting to simulate observations expected from the Five-hundred-meter Aperture Spherical radio Telescope(FAST), and discuss its potential for improving our description of the outer regions of circumstellar shells.展开更多
基金the Vietnam National Satellite Centre(VNSC/VAST)the NAFOSTED funding agency+3 种基金the World Laboratorythe Odon Vallet Foundationthe Rencontres du Viet Namthe PCMI programme of the CNRS for financial support
文摘Imaging studies with the Very Large Array(VLA) have revealed H I emission associated with the extended circumstellar shells of red giants. We analyze the spectral map obtained on Y CVn, a J-type carbon star on the Asymptotic Giant Branch. The H I line profiles can be interpreted with a model of a detached shell resulting from the interaction of a stellar outflow with the local interstellar medium.We reproduce the spectral map by introducing a distortion along a direction corresponding to the star's motion in space. We then use this fitting to simulate observations expected from the Five-hundred-meter Aperture Spherical radio Telescope(FAST), and discuss its potential for improving our description of the outer regions of circumstellar shells.