Results 11 to 20 of about 4,364 (222)

Experimental Phase Function and Degree of Linear Polarization of Light Scattered by Hydrogenated Amorphous Carbon Circumstellar Dust Analogs [PDF]

The Astrophysical Journal Supplement Series, 2023
Astronomical observations of the polarized intensity of scattered visible light have revealed the presence of dust envelopes around different types of evolved stars.
Juan Carlos Gómez Martín, Olga Muñoz, Julia Martikainen, Daniel Guirado, Isabel Tanarro, Ramón J. Peláez, Belén Maté, Miguel Jiménez-Redondo, Víctor J. Herrero, Marco Peiteado, Teresa Jardiel   +10 more
doaj   +2 more sources

Circumstellar Dust and Circumstellar Extinction Curves [PDF]

Astrophysics and Space Science, 1995
We have calculated the circumstellar extinction curves produced by dust grains which absorb and scatter the stellar radiation in the shells of pre-main-sequence stars. A Monte Carlo method was used to model the radiative transfer in non-spherical shells. The dependence on the particle size distribution and the dust shell parameters has been examined.
Voshchinnikov, N.V., Molster, F.J., The, P.S.   +2 more
openaire   +6 more sources

From Dust to Nanodust: Resolving Circumstellar Dust from the Colliding-wind Binary Wolf-Rayet 140 [PDF]

The Astrophysical Journal, 2023
Wolf-Rayet (WR) 140 is the archetypal periodic dust-forming colliding-wind binary that hosts a carbon-rich WR (WC) star and an O-star companion with an orbital period of 7.93 yr and an orbital eccentricity of 0.9.
Ryan M. Lau, Jason Wang, Matthew J. Hankins, Thayne Currie, Vincent Deo, Izumi Endo, Olivier Guyon, Yinuo Han, Anthony P. Jones, Nemanja Jovanovic, Julien Lozi, Anthony F. J. Moffat, Takashi Onaka, Garreth Ruane, Andreas A. C. Sander, Samaporn Tinyanont, Peter G. Tuthill, Gerd Weigelt, Peredur M. Williams, Sebastien Vievard   +19 more
doaj   +5 more sources

Dust in circumstellar disks [PDF]

, 2006
This thesis presents observational and theoretical studies of the size and spatial distribution of dust particles in circumstellar disks. Using millimetre interferometric observations of optically thick disks around T Tauri stars, I provide conclusive evidence for the presence of millimetre- to centimetre-sized dust aggregates.
Rodmann, Jens
openaire   +3 more sources

Composite grains: Application to circumstellar dust [PDF]

Atti della Accademia Peloritana dei Pericolanti : Classe di Scienze Fisiche, Matematiche e Naturali, 2011
Using the discrete dipole approximation (DDA) we calculate the absorption efficiency of the composite grain, made up of a host silicate spheroid and inclusions of graphite, in the spectral region 5.0-25.0μm.
D. B. Vaidya, R. Gupta
doaj   +3 more sources

Sudden Extreme Obscuration of a Sun-like Main-sequence Star: Evolution of the Circumstellar Dust around ASASSN-21qj [PDF]

The Astrophysical Journal, 2023
ASASSN-21qj is a distant Sun-like star that recently began an episode of deep dimming events after no prior recorded variability. Here we examine archival and newly obtained optical and near-infrared data of this star.
Jonathan P. Marshall, Steve Ertel, Francisca Kemper, Carlos del Burgo, Gilles P. P. L. Otten, Peter Scicluna, Sascha T. Zeegers, Álvaro Ribas, Oscar Morata   +8 more
doaj   +2 more sources

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

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   +2 more sources

Atacama Large Aperture Submillimeter Telescope (AtLAST) science: Our Galaxy [version 2; peer review: 2 approved] [PDF]

Open Research Europe
As we learn more about the multi-scale interstellar medium (ISM) of our Galaxy, we develop a greater understanding for the complex relationships between the large-scale diffuse gas and dust in Giant Molecular Clouds (GMCs), how it moves, how it is ...
Pamela Klaassen, Maria Beltrán, Alessio Traficante, Mark Booth, Kate Pattle, Jonathan Marshall, Joshua Lovell, Brandt Gaches, Alvaro Hacar, Nicolas Peretto, Caroline Bot, Doris Arzoumanian, Thomas Stanke, Gaspard Duchêne, Ana Duarte Cabral, Antonio Hales, David Eden, Patricia Luppe, Jens Kauffmann, Elena Redaelli, Sebastian Marino, Álvaro Sánchez-Monge, Andrew Rigby, Dmitry Semenov, Eugenio Schisano, Mark Thompson, Silvia Spezzano, Claudia Cicone, Friedrich Wyrowski, Martin Cordiner, Tony Mroczkowski, Doug Johnstone, Luca Di Mascolo, Minju Lee, Eelco van Kampen, Thomas Maccarone, Daizhong Liu, Matthew Smith, Amélie Saintonge, Sven Wedemeyer, Alexander Thelen   +40 more
doaj   +2 more sources

NIKA2 observations around LBV stars Emission from stars and circumstellar material [PDF]

EPJ Web of Conferences, 2020
Luminous Blue Variable (LBV) stars are evolved massive objects, previous to core-collapse supernova. LBVs are characterized by photometric and spectroscopic variability, produced by strong and dense winds, mass-loss events and very intense UV radiation ...
Ricardo Rizzo J., Ritacco Alessia, Bordiu Cristobal   +2 more
doaj   +1 more source

Is Phenylnitrene a Missing Link in the Formation of Polycyclic Aromatic Nitrogen Heterocycles? [PDF]

Angew Chem Int Ed Engl
A new formation pathway for polycyclic aromatic nitrogen heterocycles (PANHs) has been found. The reaction of phenylnitrene and the propargyl radical leads to quinoline, proving that nitrenes are suitable precursors for nitrogen incorporation mechanisms.
Arns R, McClish R, Hemberger P, Bodi A, Bouwman J, Kasper T, Schleier D.   +6 more
europepmc   +2 more sources