The following document lists the file abstract/SVWB_SBDSK11.abs
from catalogue VI/111.
A plain copy of the file
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===================================================================== ==> In this proposal, more time is being requested for SVWB.SBDSK4 ===================================================================== We propose to test the hypothesis that stellar angular momentum is regulated during the pre-main sequence phase via coupling of the star to its circumstellar disk. Previous work has shown that classical T Tauri stars with massive circumstellar disks (0.01 Msun) rotate more slowly than their weak-emission counterparts which lack such disks. These observations found a natural explanation in models where the evolution of stellar angular momentum is regulated through magnetic coupling with a circumstellar disk. A sample of 10 rapidly rotating (P < 1 day) and 10 slowly rotating (P > 1 day) solar-mass stars has been selected in the young open cluster Alpha Per. We will survey these stars with the ISOPHOT instrument in order to detect the presence of optically-thin remnant circumstellar disks. Recent models suggest that solar-type stars with rotation periods much greater than 1 day should have remained coupled to their disks for greater than 10 Myr. Remnant disks around the slowest rotating (P 6 days) stars in Alpha Per cluster (age 50 Myr) should have just begun to dissipate after the termination of the disk-locking phase. With these carefully designed ISO measurements we should be able to; i) examine the connection between stellar rotation and the presence of disk material; and ii) determine the overall frequency of optically-thin circumstellar material around low-mass stars in Alpha Per. This proposal is a key component of a two-part follow-up to the program EVOLUTION OF CIRCUMSTELLAR DISKS by Beckwith et al. awarded GTO time in the first ISO call for proposals.