Results 51 to 60 of about 1,537 (221)

JWST Imaging of the Closest Globular Clusters—VI. The Lowest‐Mass Objects in M 4 and the Galactic Bulge

open access: yesAstronomische Nachrichten, Volume 346, Issue 9, November 2025.
ABSTRACT We present James Webb Space Telescope observations of M 4—the closest globular cluster—that probe the lower Main Sequence down to the hydrogen‐burning limit. The unveiled stellar sequence reaches much fainter luminosities than previously possible, revealing a few extremely red objects that are consistent with brown dwarfs as cool as Teff∼1000K$
L. R. Bedin   +10 more
wiley   +1 more source

A Search for Asymmetric Kinematic Components in Circumstellar Envelopes Using OH Main Line Masers

open access: yesThe Astrophysical Journal
Circumstellar OH maser lines are useful for studying the dynamics of the circumstellar envelope (CSE) around evolved stars. This study aims to identify CSEs around cold stars, which exhibit deviations from the spherical expansion, by comparing the ...
Jia-Yong Xie   +2 more
doaj   +1 more source

ALMA’s Acute View of pPNe: Through the Magnifying Glass... and What We Found There

open access: yesGalaxies, 2018
We present recent Atacama Large Millimeter/submillimeter Array (ALMA)-based studies of circumstellar envelopes (CSEs) around Asymptotic Giant Branch (AGB) stars and pre-Planetary Nebulae (pPNe).
Carmen Sánchez Contreras   +3 more
doaj   +1 more source

Polarized Maser Emission with In-source Faraday Rotation

open access: yesThe Astrophysical Journal, 2023
We discuss studies of polarization in astrophysical masers with particular emphasis on the case where the Zeeman splitting is small compared to the Doppler profile, resulting in a blend of the transitions between magnetic substates.
T. L. Tobin, M. D. Gray, A. J. Kemball
doaj   +1 more source

Clusters Stagnating During Condensation: Metastable Material or a Separate State of Matter?

open access: yesAnnalen 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

Early Planet Formation in Embedded Disks (eDisk). XVII. A Compact but Structured Keplerian Disk and Large-scale Streamers Revealed in the Class I Protostellar System IRAS 04169+2702

open access: yesThe Astrophysical Journal
We present high-resolution (∼0 $\mathop{.}\limits^{^{\prime\prime} }$ 05; 8 au) dust continuum and molecular line observations toward the Class I protostellar system IRAS 04169+2702 in the Taurus B213 region, as part of the Atacama Large Millimeter ...
Ilseung Han   +24 more
doaj   +1 more source

Linear or Cyclic? Theoretical Investigation of Astrophysically Relevant Magnesium‐Bearing MgCnH Carbon Chains and Related Isomers

open access: yesJournal of Computational Chemistry, Volume 46, Issue 2, January 15, 2025.
The global minimum energy structure of astrophysically relevant MgCnH systems is linear when n is even, and cyclic when n is odd. ABSTRACT Magnesium‐containing molecules, including MgC2H, MgC4H, and MgC6H, have been detected in the interstellar medium, largely facilitated by their high dipole moments.
A. Karolyna M. S. Gomes   +3 more
wiley   +1 more source

Reflections on the photodissociation of CO in circumstellar envelopes

open access: yes, 2021
Carbon monoxide (CO) is the most abundant molecule after molecular hydrogen and is important for the chemistry in circumstellar envelopes around evolved stars.
M. A. T. Groenewegen   +3 more
core   +1 more source

Excited-state OH Masers in the Water Fountain Source IRAS 18460-0151

open access: yesThe Astrophysical Journal Letters
Water fountain objects are generally defined as evolved stars with low to intermediate initial mass accompanied by high-velocity molecular jets detectable in the 22.235 GHz H _2 O maser line.
Xu-Jia Ouyang   +5 more
doaj   +1 more source

On Circumstellar Envelope Formation

open access: yesThe Astrophysical Journal, 1997
The origin of magnetic fields observed in circumstellar envelopes and proto-planetary nebulae is investigated theoretically. The build-up region of these fields is likely to be found deep in the progenitor (assumed to be an asymptotic giant branch red giant).
openaire   +1 more source

Home - About - Disclaimer - Privacy