Results 51 to 60 of about 353 (134)

Long-Term Spectroscopic Monitoring and Surveys of Early-Type Stars with and without Circumstellar Envelopes

Open Astronomy, 2017
Ongoing studies of different groups of stars result in improving our knowledge of their fundamental parameters and evolutionary status. Also, they result in finding new phases of stellar evolution, which require theoretical explanation. At the same time,
Miroshnichenko Anatoly S., Danford Steven, Zharikov Sergei V., Manset Nadine, Levato Hugo, Grosso Monica, Korčáková Daniela, Kusakin Anatoly V., Khokhlov Serik A., Prendergast Peter   +9 more
doaj   +1 more source

Multiple Protostellar Outflows from a Single Protostar with a Misaligned Disk

The Astrophysical Journal
We investigate how misalignment between the core angular momentum and the large-scale magnetic field affects protostellar outflows, and whether a single protostellar system can drive multiple outflow components.
Shingo Hirano, Yuri Aikawa, Masahiro N. Machida   +2 more
doaj   +1 more source

Theoretical study on the reaction mechanism of cyclopropenylidene with cyclic CnH2nO (n = 2, 3) compounds: Ring expansion process

Journal of Saudi Chemical Society, 2016
The ring expansion reaction mechanisms between cyclopropenylidene and cyclic CnH2nO (n = 2, 3) compounds have been systematically investigated employing the second-order Møller-Plesset perturbation theory (MP2) method in order to better understand the ...
Xiaojun Tan, Weihua Wang, Ping Li
doaj   +1 more source

The dusty envelopes of asymptotic giant branch stars with ultraviolet excesses

Astronomy & Astrophysics
Context. Roughly spherical envelopes around asymptotic giant branch (AGB) stars transform into the highly asymmetric morphologies observed in planetary nebulae.
Alonso-Hernández J., Sánchez Contreras C., Sahai R., Sanz-Forcada J.   +3 more
doaj   +1 more source

Protostellar Chimney Flues: Are Jets and Outflows Lifting Submillimeter Dust Grains from Disks into Envelopes?

The Astrophysical Journal
Low dust opacity spectral indices ( β < 1) measured in the inner envelopes of class 0/I young stellar objects (age ∼10 ^4–5 yr) have been interpreted as the presence of (sub-)millimeter dust grains in these environments.
L. Cacciapuoti, L. Testi, L. Podio, C. Codella, A. J. Maury, M. De Simone, P. Hennebelle, U. Lebreuilly, R. S. Klessen, S. Molinari   +9 more
doaj   +1 more source

Observational astrochemistry: The quest for interstellar molecules

EPJ Web of Conferences, 2012
Over 160 molecular species, not counting isotopologues, have been identified in circumstellar envelopes and interstellar clouds. These species have revealed a wealth of familiar, as much as exotic molecules and in complex organic (and silicon) compounds,
Guélin M.
doaj   +1 more source

Properties of Carbon-rich Asymptotic Giant Branch Stars in the LMC and the Milky Way

The Astrophysical Journal
We present a comparative study of carbon-rich asymptotic giant branch (CAGB) stars in the Large Magellanic Cloud (LMC; 7347 stars) and the Milky Way (7163 stars) using infrared color–magnitude diagrams, spectral energy distributions (SEDs), two-color ...
Kyung-Won Suh
doaj   +1 more source

Red and Yellow Hypergiants

Galaxies
The red and yellow hypergiants are a rare and important phase in the evolution of the most massive stars that can reach the cool part of the HR Diagram.
Terry Jones
doaj   +1 more source

Systematic Search for Water Fountain Candidates Using the Databases of Circumstellar Maser Sources

The Astrophysical Journal Supplement Series
Water fountains (WFs) are thought to be objects in the morphological evolution of the circumstellar envelopes of low- and intermediate-mass evolved stars, transitioning from spherically symmetric to asymmetric shapes.
Haichen Fan, Jun-ichi Nakashima, D. Engels, Yong Zhang, Jian-Jie Qiu, Huan-Xue Feng, Jia-Yong Xie, Hiroshi Imai, Chih-Hao Hsia   +8 more
doaj   +1 more source

87th Annual Meeting of the Meteoritical Society 2025: Abstracts

Meteoritics &Planetary Science, Volume 60, Issue S1, Page 30-350, August 2025.
wiley   +1 more source