From: LARRY KLAES (ljk4_at_msn.com)
Date: Tue May 31 2005 - 00:19:14 PDT
Paper: astro-ph/0505562
Date: Fri, 27 May 2005 17:12:52 GMT (830kb)
Title: X-Ray Flares of Sun-Like Young Stellar Objects and Their Effects on
Protoplanetary Disks
Authors: A. E. Glassgold, E.D. Feigelson, T. Momtmerle, S. Wolk
Comments: 17 pages, 5 figures, ASP style
\\
Astronomical observations of flares from analogs of the early Sun have the
potential to give critical insights into the high energy irradiation
environment of protoplanetary disks. Solar-mass young stellar objects are
significantly more X-ray luminous than the typical low-mass T Tauri star.
They
undergo frequent strong flaring on a several day time scale. Very powerful
flares also occur, but on a longer time frame. The hard X-ray spectrum of
these
stars become even harder during flaring. The X-rays from these sun-like
young
stellar objects have the potential to ionize circumstellar material out to
large distances. Three specific illustrations are given of the effects of
the
X-rays: The physics and chemistry of the atmospheres of the inner accretion
disks; the ionization level at the disk midplane, important for the
viability
of the magnetorotational instability; and the nuclear fluence in the
irradiation zone just interior to the inner edge of the disk, important in
local irradiation scenarios for producing the short-lived radionuclides
found
in meteorites.
\\ ( http://arXiv.org/abs/astro-ph/0505562 , 830kb)
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