Results 71 to 80 of about 1,537 (221)

Limitations of the modified blackbody fit method for determining molecular cloud properties

Astronomische Nachrichten, Volume 345, Issue 4, May 2024.
Abstract Achieving a comprehensive understanding of the star and planet formation process is one of the fundamental tasks of astrophysics, requiring detailed knowledge of the physical conditions during the different phases of this process. During the earliest stages, that is, concerning physical processes in molecular clouds and filaments, the column ...
Niko Zielinski, Sebastian Wolf
wiley   +1 more source

Early Planet Formation in Embedded Disks (eDisk). XIII. Aligned Disks with Nonsettled Dust around the Newly Resolved Class 0 Protobinary R CrA IRAS 32

The Astrophysical Journal
Young protostellar binary systems, with expected ages less than ∼10 ^5 yr, are little modified since birth, providing key clues to binary formation and evolution. We present a first look at the young, Class 0 binary protostellar system R CrA IRAS 32 from
Frankie J. Encalada, Leslie W. Looney, Shigehisa Takakuwa, John J. Tobin, Nagayoshi Ohashi, Jes K. Jørgensen, Zhi-Yun Li, Yuri Aikawa, Yusuke Aso, Patrick M. Koch, Woojin Kwon, Shih-Ping Lai, Chang Won Lee, Zhe-Yu Daniel Lin, Alejandro Santamaría-Miranda, Itziar de Gregorio-Monsalvo, Nguyen Thi Phuong, Adele Plunkett, Jinshi Sai (Insa Choi), Rajeeb Sharma, Hsi-Wei Yen, Ilseung Han   +21 more
doaj   +1 more source

Characterizing the dynamical magnetosphere of the extremely slowly rotating magnetic O9.7 V star HD 54879 using rotational modulation of the Hα profile

Astronomische Nachrichten, Volume 345, Issue 4, May 2024.
Abstract The magnetic field in the O9.7 V star HD 54879 has been monitored for almost a decade. Spectropolarimetric observations reveal a rather strong mean longitudinal magnetic field that varies with a period of about 7.41 years. Observations in the Hα$$ \alpha $$ line show a variation with the same period, while the Hβ$$ \beta $$ line shows only ...
Manfred Küker, S. P. Järvinen, S. Hubrig, Ilya Ilyin, M. Schöller   +4 more
wiley   +1 more source

Do Water Fountain Jets Really Indicate the Onset of the Morphological Metamorphosis of Circumstellar Envelopes? [PDF]

, 2016
The small-scale bipolar jets having short dynamical ages from “water fountain (WF)” sources are suggested to be indicating the onset of morphological metamorphosis of circumstellar envelopes of intermediate-mass stars. Such process usually happens at the
Yung, B. H. K., Nakashima, J, Imai, I, Hsia, C   +3 more
core   +1 more source

A deep search for C2H in the oxygen-rich post-AGB star OH 231.8+4.2

Frontiers in Astronomy and Space Sciences
In carbon-rich environment, C2H emission is seen to be associated with HC3N, but whether it can trace the HC3N molecule in oxygen-rich environment is unknown.
Jianchao Yang, Jianchao Yang, Xiaofeng Yang, Xiaofeng Yang, Cheng Zhu, Cheng Zhu   +5 more
doaj   +1 more source

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

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   +1 more source

The Circumstellar Envelope of pi Gru

, 1999
CO(J = 2-1) and SiO(J = 5-4) emission has been observed from the molecular envelope around the nearby S star pi Gru. The CO line profile differs from the usual parabolic shape seen in uniformly expanding envelopes; it has a Voigt-like profile and two horns.
Knapp, G. R., Young, K., Crosas, M.
openaire   +2 more sources

Interferometric view of the circumstellar envelopes of northern FU Orionis-type stars

, 2017
Context. FU Orionis-type objects are pre-main sequence, low-mass stars with large outbursts in visible light that last for several years or decades. They are thought to represent an evolutionary phase during the life of every young star when accretion ...
Kóspál, Á., P. Ábrahám, Á. Kóspál, M. R. Hogerheijde, Fehér, O., Fehér, Orsolya, Ábrahám, Péter, Kóspál, Ágnes, O. Fehér, C. Brinch, Ábrahám, P., Hogerheijde, M.R., Brinch, C., Hogerheijde, M. R.   +13 more
core   +1 more source

Asymptotic giant branch stars in the Large Magellanic Cloud: evolution of dust in circumstellar envelopes [PDF]

, 2015
We calculated theoretical evolutionary sequences of asymptotic giant branch (AGB) stars, including the formation and evolution of dust grains in their circumstellar envelopes.
SCHNEIDER, Raffaella, VENTURA, Paolo, García-Hernández, D. A., DELL'AGLI, FLAVIA, BROCATO, Enzo, Ventura, P., García Hernández, D. A., Di Criscienzo, M., ROSSI, Corinne, Dell'Agli, F., DI CRISCIENZO, Marcella, Brocato, E., Rossi, C.   +12 more
core   +1 more source

Observations of Molecular CN toward S-type Asymptotic Giant Branch Stars

The Astronomical Journal
S-type asymptotic giant branch (AGB) stars are defined by their carbon-to-oxygen (C/O) ratio approaching unity. However, observations of circumstellar molecules in these stars are limited and challenging.
Yanan Feng, Xiaohu Li, Xiaofeng Yang, Tom J. Millar, Ryszard Szczerba, Sheng-Li Qin, Xuejian Jiang, Donghui Quan, Juan Tuo, Zhenzhen Miao, Sheng-Yuan Liu, Xiang Liu   +11 more
doaj   +1 more source