Results 91 to 100 of about 1,537 (221)
Polarimetry as a Diagnostic of Circumstellar Envelopes [PDF]
International Astronomical Union Colloquium, 2000 AbstractPolarimetric observations of stars can provide useful diagnostics of the geometry and physical conditions of the circumstellar envelope. This paper reviews the application of polarimetric techniques to hot stars (with particular emphasis on Be stars) and the status of polarization observations, and discusses some recent developments that ...
openaire +1 more source
SiO maser emission as a density tracer of circumstellar envelopes
, 2018 The circumstellar envelopes (CSEs) of evolved stars offer a method to construct a sample of point-masses along the full Galactic plane, which can be used to test models of the gravitational potential.
Morris, M. R. (5944070) +11 more
core +1 more source
Characterizing circumstellar disk around young stars
, 2010 The circumstellar disks play a fundamental role in star and planet formation process. Studies on circumstellar disks are generally carried on following two viable approaches: "statistical" studies, where a large samples of sources are measured to ...
Schisano, Eugenio
core
The dusty envelopes of asymptotic giant branch stars with ultraviolet excesses
Astronomy & AstrophysicsContext. Roughly spherical envelopes around asymptotic giant branch (AGB) stars transform into the highly asymmetric morphologies observed in planetary nebulae.
Alonso-Hernández J. +3 more
doaj +1 more source
The circumstellar envelope of IRC +10216
The Astrophysical Journal, 1977 The circumstellar envelope of IRC+10216, a late-type carbon star, is modeled, and theoretical calculations of CO, /sup 13/CO, HCN, and H/sup 13/CN emission are compared with observations. A steady mass loss from the star is assumed. The gas temperature in the flow is determined from considerations of the cooling due to free expansion and molecular ...
J. Kwan, F. Hill
openaire +1 more source
Circumstellar disks and envelopes around young low-mass stars
, 2007 In this PhD thesis astronomical observations of the immediate surroundings of young low-mass stars are presented and interpreted. Particular emphasis is put on FU Orionis stars (FUors).
Quanz, Sascha Patrick, Quanz, S. P.
core +1 more source
The Astrophysical JournalLow dust opacity spectral indices ( β < 1) measured in the inner envelopes of class 0/I young stellar objects (age ∼10 ^4–5 yr) have been interpreted as the presence of (sub-)millimeter dust grains in these environments.
L. Cacciapuoti +9 more
doaj +1 more source
Observational astrochemistry: The quest for interstellar molecules
EPJ Web of Conferences, 2012 Over 160 molecular species, not counting isotopologues, have been identified in circumstellar envelopes and interstellar clouds. These species have revealed a wealth of familiar, as much as exotic molecules and in complex organic (and silicon) compounds,
Guélin M.
doaj +1 more source
Variability in the Circumstellar Envelope of Be Stars [PDF]
Symposium - International Astronomical Union, 1994 A progress report will be given on recent studies of circumstellar variability of Be stars, their implications on the formation process, the dynamics, the structure and the morphology of the envelope. The following points are discussed: recurrence of outbursts, simultaneous infall and outflow events, variability in hot regions versus variability in the
openaire +1 more source
Formation of SiC grains and the 11.3μm feature in circumstellar envelopes of carbon stars. [PDF]
, 1996 We propose that the so-called 11.3μm emission features observed toward carbon stars can be attributed to small spherical core-mantle type grains consisting of a SiC core and a carbon mantle or small carbon grains containing SiC as an impurity.
Henning, Thomas +3 more
core