Interferometric Studies of Dust Formation in the Red Supergiant Star S Persei
Abstract
Few methods are as effective as interferometry for probing the dust formation regions around evolved stars at high spatial scales. Using multi-epoch VLBA monitoring observations of 43 GHz SiO (v=1J=1-0) maser emission Ostrowski-Fukuda et al.(2003 AAS meeting 201 poster 115) found that the red supergiant S Persei exhibits clumpy and variable SiO maser spots in a broken elongated (elliptical) ring approximately 23 by 16 milli-arcsec with the semi-major axis oriented in the northeast-southwest (NE-SW) direction. Independent K band interferometry (PTI group Creech-Eakman and Thompson) obtained a limb darkened diameter for S Per of 5 mas similarly oriented. These facts combined suggest that the masers constitute a standing wave phenomenon associated with rapid particle formation at ~2 stellar radii. We present these results and a model for this phenomenon.
- Publication:
-
Stars as Suns : Activity, Evolution and Planets
- Pub Date:
- January 2004
- Bibcode:
- 2004IAUS..219..925S