Results 31 to 40 of about 717 (184)
The Astronomical JournalMany 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 +3 more
doaj +1 more source
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
Satellites and Small Bodies With ALMA: Insights Into Solar System Formation and Evolution
AGU Advances, Volume 6, Issue 6, December 2025.Abstract Our understanding of the formation and evolution of planetary systems has made major advances in the past decade. This progress has been driven in large part by the Atacama Large Millimeter/submillimeter Array (ALMA), which has given us an unprecedented view of solar system bodies themselves, and of the structure and chemistry of forming ...
Katherine de Kleer +3 more
wiley +1 more source
Composite grains: Application to circumstellar dust
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 +1 more source
Clusters Stagnating During Condensation: Metastable Material or a Separate State of Matter?
Annalen der Physik, Volume 537, Issue 10, October 2025.Condensation stagnation, that is, the existence of a delay between nucleation and growth during the gas‐phase particle formation, is a crucial phenomenon, which manifests itself as the presence of supercritical clusters in resulting particulates. The light emission signature of stagnant clusters is identified in the magnesium particle flame in air, and,
Nicholas R. Jaramillo +4 more
wiley +1 more source
Dust motion and possibility of dust growth in a growing circumstellar disk
Monthly Notices of the Royal Astronomical Society, 2022 ABSTRACT We calculate the evolution of a star-forming cloud core using a three-dimensional resistive magnetohydrodynamics simulation, treating dust grains as Lagrangian particles, to investigate the dust motion in the early star formation stage.
Shunta Koga, Masahiro N Machida
openaire +2 more sources
Near-infrared Integral-field Spectroscopy of the Wind Forming Region of CW Leo
The Astronomical JournalThe circumstellar envelope of the carbon star CW Leo exhibited various unexpected changes in recent optical imaging observations. We have performed a follow-up observation using the Near-infrared Integral-Field Spectrograph (NIFS) equipped on the Gemini ...
Hyosun Kim +3 more
doaj +1 more source
Circumstellar dust emission models
The Astrophysical Journal, 1994 We present the wavelength-dependent absorption coefficient K(sub lambda) the scattering coefficient o(sub lambda), the albedo w(sub lambda), and the average cosine of the scattering phase function g(sub lambda) between 0.0912 micrometers and 1000 micrometers for four interstellar medium grain models.
Mark G. Wolfire, Ed Churchwell
openaire +1 more source
L1448 IRS3B: Dust Polarization Aligned with Spiral Features, Tracing Gas Flows
The Astrophysical JournalCircumstellar disk dust polarization in the (sub)millimeter is, for the most part, not from dust grain alignment with magnetic fields but rather indicative of a combination of dust self-scattering with a yet unknown alignment mechanism that is consistent
Leslie W. Looney +13 more
doaj +1 more source
JWST Imaging of the Closest Globular Clusters—V. The White Dwarfs Cooling Sequence of M4
Astronomische Nachrichten, Volume 346, Issue 2, February 2025.ABSTRACT We combine infrared (IR) observations collected by the James Webb Space Telescope with optical deep images by the Hubble Space Telescope taken ~20 years earlier to compute proper‐motion membership for the globular cluster (GC) M4 (NGC 6121) along its entire white dwarf (WD) cooling sequence (CS).
Luigi R. Bedin +11 more
wiley +1 more source