Results 61 to 70 of about 386,435 (271)

Laboratory Astrophysics of Circumstellar Dust [PDF]

Symposium - International Astronomical Union, 1999
This paper summarizes laboratory investigations of Stardust analogue materials with special emphasis on the spectroscopic behaviour of silicates and carbonaceous materials. The review will also deal with the identification of the observed features in the dust spectra of AGB stars.
openaire   +1 more source

Sublimation temperature of circumstellar dust particles and its importance for dust ring formation [PDF]

, 2011
Dust particles in orbit around a star drift toward the central star by the Poynting-Robertson effect and pile up by sublimation. We analytically derive the pile-up magnitude, adopting a simple model for optical cross sections.
H. Kobayashi, H. Kimura, Sei‐ichiro Watanabe, Tetsuo Yamamoto, S. Mueller   +4 more
semanticscholar   +1 more source

A Coronagraphic Pilot Study of the Circumstellar Environments around Red Supergiants: CD -31°4916’s Dust Morphology

The Astronomical Journal
Many mechanisms have been proposed to contribute to massive-star mass loss, but in general little is known about the physics involved. Studies of circumstellar environments around massive stars might help to determine which mechanisms are the most common.
Jamie R. Lomax, Emily M. Levesque, John P. Wisniewski, John H. Debes   +3 more
doaj   +1 more source

Rapid formation of large dust grains in the luminous supernova SN 2010jl

, 2014
The origin of dust in galaxies is still a mystery. The majority of the refractory elements are produced in supernova explosions but it is unclear how and where dust grains condense and grow, and how they avoid destruction in the harsh environments of ...
Day-Jones, Avril C., Dwek, Eli, Fox, Ori, Gall, Christa, Hjorth, Jens, Leloudas, Giorgos, Malesani, Daniele, Maund, Justyn R., Watson, Darach   +8 more
core   +1 more source

New constraints on dust grain size and distribution in CQ Tau [PDF]

, 2010
Grain growth in circumstellar disks is expected to be the first step towards the formation of planetary systems. There is now evidence for grain growth in several disks around young stars.
A. Banzatti, A. Isella, A. Natta, Andre, Andrews, Beckwith, Birnstiel, Birnstiel, Brauer, Chapillon, Chiang, Chiang, D. J. Wilner, Draine, Dullemond, Franco, Guedel, Hughes, Isella, Isella, Isella, Isella, L. Testi, Lissauer, Lommen, Mannings, Mannings, Mezger, Miyake, Panagia, Perryman, Pollack, R. Neri, Ricci, Rodmann, Skinner, Testi, Testi, Wilner, Wilner   +39 more
core   +3 more sources

Circumstellar dust as a solution to the red supergiant supernova progenitor problem [PDF]

, 2011
We investigate the red supergiant problem, the apparent dearth of Type IIP supernova progenitors with masses between 16 and 30M⊙. Although red supergiants with masses in this range have been observed, none have been identified as progenitors in pre ...
J. Walmswell, J. Eldridge
semanticscholar   +1 more source

The temperature of nonspherical circumstellar dust grains [PDF]

Astronomy Letters, 2000
The temperatures of prolate and oblate spheroidal dust grains in the envelopes of stars of various spectral types are calculated. Homogeneous particles with aspect ratios {\small $a/b \le 10$} composed of amorphous carbon, iron, dirty ice, various silicates, and other materials are considered. The temperatures of spherical and spheroidal particles were
Voshchinnikov, N. V., Semenov, D. A.
openaire   +2 more sources

Confined Chemistry in Space: Zeolite‐Supported Fe13 Nanoclusters Modulate CS Reactivity

Small Structures, Volume 7, Issue 3, March 2026.
The study explores how an Fe13 cluster confined in chabazite reshapes the reaction of CS and H2 under astrochemical conditions. Confinement promotes C–S bond cleavage over hydrogenation, directing chemistry toward CH4 and H2S formation. Additional CS enables CS2 and C2 species. Microkinetic analysis identifies protoplanetary environments where zeolites
Gerard Pareras, Albert Rimola
wiley   +1 more source

ISO spectroscopy of circumstellar dust in 14 Herbig Ae/Be systems: Towards an understanding of dust processing [PDF]

, 2000
We present Infrared Space Observatory (ISO) spectra of fourteen isolated Herbig Ae/Be (HAEBE) stars, to study the characteristics of their circumstellar dust. These spectra show large star-to-star differences, in the emission features of both carbon-rich
G. Meeus, L. Waters, L. Waters, J. Bouwman, M. V. D. Ancker, M. V. D. Ancker, C. Waelkens, K. Malfait   +7 more
semanticscholar   +1 more source

The Circumstellar Dust of “Born-Again” Stars [PDF]

EAS Publications Series, 2015
We describe the evolution of the carbon dust shells around Very Late Thermal Pulse (VLTP) objects as seen at infrared wavelengths. This includes a 20-year overview of the evolution of the dust around Sakurai's object (to which Olivier made a seminal contribution) and FG Sge. VLTPs may occur during the endpoint of as many as 25% of solar mass stars, and
Evans, A., Gehrz, R. D., Helton, L. A., Woodward, C. E.   +3 more
openaire   +2 more sources