TY - JOUR
T1 - Stellar structure and mass loss on the upper asymptotic giant branch
AU - Soker, Noam
AU - Harpaz, Amos
N1 - Copyright:
Copyright 2017 Elsevier B.V., All rights reserved.
PY - 1999/12/21
Y1 - 1999/12/21
N2 - We examine the envelope properties of asymptotic giant branch (AGB) stars as they evolve on the upper AGB and during the early post-AGB phase. Because of the high mass-loss rate, the envelope mass decreases by more than an order of magnitude. This makes the density profile below the photosphere much shallower, and the entropy profile much steeper. We discuss the possible role of these changes in the profiles in the onset of the high mass-loss rate (superwind) and the large deviation from spherical mass loss at the termination of the AGB. We concentrate on the idea that the shallower density profile and steeper entropy profile allow the formation of cool magnetic spots, above which dust forms much more easily.
AB - We examine the envelope properties of asymptotic giant branch (AGB) stars as they evolve on the upper AGB and during the early post-AGB phase. Because of the high mass-loss rate, the envelope mass decreases by more than an order of magnitude. This makes the density profile below the photosphere much shallower, and the entropy profile much steeper. We discuss the possible role of these changes in the profiles in the onset of the high mass-loss rate (superwind) and the large deviation from spherical mass loss at the termination of the AGB. We concentrate on the idea that the shallower density profile and steeper entropy profile allow the formation of cool magnetic spots, above which dust forms much more easily.
KW - Circumstellar matter
KW - Planetary nebulae: general
KW - Stars: AGB and post-AGB
KW - Stars: magnetic fields
KW - Stars: mass-loss
UR - http://www.scopus.com/inward/record.url?scp=0041010872&partnerID=8YFLogxK
U2 - 10.1046/j.1365-8711.1999.03062.x
DO - 10.1046/j.1365-8711.1999.03062.x
M3 - 文章
AN - SCOPUS:0041010872
VL - 310
SP - 1158
EP - 1164
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
SN - 0035-8711
IS - 4
ER -