Results 51 to 60 of about 55,649 (206)

Photochemical origin of SiC2 in the circumstellar envelope of carbon-rich AGB stars revealed by ALMA

Frontiers in Astronomy and Space Sciences, 2023
The fact that whether SiC2 is a parent species, formed in the photosphere or as a by-product of high-temperature dust formation, or a daughter species, formed in chemistry driven by the photodestruction of the parent species in the outer envelope, has ...
Yanan Feng, Yanan Feng, Xiaohu Li, Xiaohu Li, Tom J. Millar, Ryszard Szczerba, Ke Wang, Donghui Quan, Donghui Quan, Shengli Qin, Shengli Qin, Xuan Fang, Xuan Fang, Xuan Fang, Xuan Fang, Juan Tuo, Juan Tuo, Zhenzhen Miao, Rong Ma, Rong Ma, Fengwei Xu, Fengwei Xu, Jingfei Sun, Biwei Jiang, Biwei Jiang, Qiang Chang, Jianchao Yang, Jianchao Yang, Gao-Lei Hou, Fangfang Li, Yong Zhang, Yong Zhang, Yong Zhang   +32 more
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, Cole A. Ritchie, Michelle L. Pantoya, Igor E. Agranovski, Igor Altman   +4 more
wiley   +1 more source

The photodissociation of CO in circumstellar envelopes [PDF]

Astronomy & Astrophysics, 2017
A&A in ...
openaire   +2 more sources

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

The 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, Jun-ichi Nakashima, Yong Zhang   +2 more
doaj   +1 more source

Polarized Maser Emission with In-source Faraday Rotation

The 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

On Circumstellar Envelope Formation

The 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

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

Journal 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, Ricardo R. Oliveira, Thiago M. Cardozo, Felipe Fantuzzi   +3 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

The 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, Woojin Kwon, Yusuke Aso, Nagayoshi Ohashi, John J. Tobin, Jes K. Jørgensen, Shigehisa Takakuwa, Leslie W. Looney, Yuri Aikawa, Christian Flores, Itziar de Gregorio-Monsalvo, Patrick M. Koch, Chang Won Lee, Jeong-Eun Lee, Zhi-Yun Li, Zhe-Yu Daniel Lin, Jinshi Sai, Travis J. Thieme, Jonathan P. Williams, Sacha Gavino, Miyu Kido, Shih-Ping Lai, Nguyen Thi Phuong, Alejandro Santamaría-Miranda, Hsi-Wei Yen   +24 more
doaj   +1 more source

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

Galaxies, 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, Javier Alcolea, Valentín Bujarrabal, Arancha Castro-Carrizo   +3 more
doaj   +1 more source

ISO results on circumstellar envelopes [PDF]

Symposium - International Astronomical Union, 1999
This review covers spectroscopic results obtained with ISO on molecular and atomic line emission from the circumstellar envelopes of oxygen-rich AGB stars and post-AGB objects and from cool supergiant stars. As well as the SWS detection of the 4.27-μm CO2 band in absorption and emission from cool star envelopes, several new emission bands which have ...
openaire   +1 more source