OT2_bsargent_1: Herschel PACS Spectroscopy of Mass Loss from Red Supergiant Stars in the Large Magellanic Cloud
Abstract
We propose to measure the thermal CO lines J = 14-13 and J = 15-14 in the circumstellar envelopes (CSEs) of 2 of the brightest red supergiant (RSG) stars at far-infrared wavelengths in the Large Magellanic Cloud (LMC) - WOH G64 and IRAS 05280-6910. CO lines are useful for measuring molecular gas, which dominates stellar winds from low-temperature stars, such as RSGs. The scientific objectives are as follows: (1) What gas mass-loss rates do LMC RSG stars experience? Mass lost from RSGs consists mainly of molecular gas, so measurements of the gas mass-loss rate are crucial. (2) Of particular interest is the influence of low metallicities, so we will compare the gas-to-dust ratios of evolved stars in the LMC (half of the solar metallicity) and those in the Galaxy. (3) Finally, our measurements will help us understand whether or not RSGs play a key role in the life-cycle of matter within galaxies (e.g., as dust and gas injectors).
- Publication:
-
Herschel Space Observatory Proposal
- Pub Date:
- September 2011
- Bibcode:
- 2011hers.prop.1690S