Results 61 to 70 of about 2,871 (139)

The photoproduction of circumstellar OH maser shells

The Astronomical Journal, 1982
The structure of OH shells formed from the photodestruction of H2O by ambient UV photons in the thick, expanding envelopes around cool evolved stars is investigated. The properties of the shells are governed mainly by the envelope shielding which in turn is primarily controlled by the mass-loss rate M. The peak OH densities and column densities through
P. J. Huggins, A. E. Glassgold
openaire   +1 more source

SiO v = 1 J = 5 → 4 Maser Emission from the Root of the “Water Fountain” Source W 43A

The Astrophysical Journal
We report here the first mapping of SiO v = 1 J  = 5 → 4 maser emission toward the “water fountain” source W 43A in order to explore the central stellar system driving the collimated, bipolar, fast jet.
Hiroshi Imai, Takeshi Hoshino, Daniel Tafoya, José F. Gómez, Jun-ichi Nakashima, Gabor Orosz   +5 more
doaj   +1 more source

OH masers in the Milky Way and Local Group galaxies in the SKA era

, 2015
The intense line emission of OH masers is a perfect tracer of regions where new stars are born aswell as of evolved stars, shedding large amounts of processed matter into the interstellar medium. From SKA deep surveys at 18 cm, where the maser lines from
Dawson, Joanne, Ellingsen, Simon, Engels, Dieter, Etoka, Sandra, Imai, Hiroshi, Sjouwerman, Lorant, van Langevelde, Huib   +6 more
core   +1 more source

The 43GHz SiO maser in the circumstellar envelope of the AGB star R Cassiopeiae

, 2011
We present multi-epoch, total intensity, high-resolution images of 43GHz, v=1, J=1-0 SiO maser emission toward the Mira variable R Cas. In total we have 23 epochs of data for R Cas at approximate monthly intervals over an optical pulsation phase range ...
Al Muntafki, Khudhair Abbas assaf, Assaf, K A, Diamond, P J, Gray, M D, Richards, A M S   +4 more
core   +1 more source

Imaging the Jet of MWC 349A with Resolved Radio Recombination Line Emission from ALMA

The Astrophysical Journal Letters
Jets and disk winds arise from materials with excess angular momentum ejected from the accretion disks in forming stars. How these structures are launched and how they impact the gas within the innermost regions of these objects remains poorly understood.
Antonio Martínez-Henares, Qizhou Zhang, Izaskun Jiménez-Serra, Jesús Martín-Pintado, Nuria Huélamo, Sirina Prasad, James Moran, Alejandro Báez-Rubio   +7 more
doaj   +1 more source

The magnetic field of the evolved star W43A

, 2009
The majority of the observed planetary nebulae exhibit elliptical or bipolar structures. Theoretical modeling has indicated that magnetically collimated jets may be responsible for the formation of the non-spherical planetary nebulae.
Amiri, N., van Langevelde, H. J., Vlemmings, W. H. T.   +2 more
core   +1 more source

A 6 cm Formaldehyde Line Survey toward WISE Point Sources

The Astrophysical Journal Supplement Series
We conducted a 6 cm formaldehyde (H _2 CO) line survey across the northern sky, targeting 3149 high-mass star-forming region candidates selected from the all-sky Wide-field Infrared Survey Explorer (WISE) point-source catalog using the Shanghai TianMa 65
Jun-Ting Liu, Xi Chen, Xu-Jia Ouyang, Yan-Kun Zhang, Shi-Min Song, Zhang Zhao, Bin Li, Bo Xia, Zhi-Qiang Shen   +8 more
doaj   +1 more source

The first detection of the 232 GHz vibrationally excited H2O maser in Orion KL with ALMA

, 2012
We investigated the ALMA science verification data of Orion KL and found a spectral signature of the vibrationally excited H2O maser line at 232.68670 GHz (nu2=1, 5,5,0-6,4,3).
Beuther, Blake, Chapman, Gaume, Hirota, Hirota, Humphreys, Kim, Reid, Zapata, Zapata   +10 more
core   +1 more source

A wide-angle outflow with the simultaneous presence of a high-velocity jet in the high-mass Cepheus A HW2 system

, 2010
We present five epochs of VLBI water maser observations around the massive protostar Cepheus A HW2 with 0.4 mas (0.3 AU) resolution. The main goal of these observations was to follow the evolution of the remarkable water maser linear/arcuate structures ...
A. C. Raga, Anglada, Bally, Banerjee, Bartkiewicz, Beuther, Bonnell, Bonnell, Cunningham, Curiel, Curiel, Curran, Davies, de Wit, G. Anglada, G. Garay, Gallimore, Garay, Gómez, Hartigan, Hartigan, Hirano, Hoare, Hoare, Hofner, Hughes, Itoh, J. Cantó, J. F. Gómez, J. M. Torrelles, Jiménez-Serra, Jiménez-Serra, Johnson, Krist, Krumholz, Krumholz, Kun, L. F. Rodríguez, Lizano, Machida, Martí, Martín-Pintado, Matthews, McKee, Minier, Moscadelli, Moscadelli, Mundt, N. A. Patel, Niezurawska, P. T. P. Ho, Parkin, Patel, Patel, Pravdo, Qiu, R. Estalella, Raga, Ray, Rodríguez, Rodríguez, S. Curiel, Santiago-García, Schneider, Shang, Shepherd, Shu, Snell, Sugiyama, Torrelles, Torrelles, Torrelles, Torrelles, Torrelles, Torrelles, Torrelles, Trinidad, Velusamy, Vlemmings, Vlemmings, W. Vlemmings, Yorke, Zapata, Zinnecker   +83 more
core   +2 more sources

Circumstellar masers around oxygen-rich stars

The Astronomical Journal, 1990
The far-IR colors of bright oxygen-rich stars define a clear sequence from sources along the blackbody curve with temperatures above 2000 K, across a small gap at color temperatures in the range 1000-2000 K, down to temperatures of about 300 K, where stars are heavily obscured.
openaire   +1 more source