Results 41 to 50 of about 4,740 (197)

The Discovery of the Zeeman Effect in 38 GHz Class II Methanol Masers

The Astrophysical Journal, 2023
Magnetic fields likely play an important role in star formation, but the number of directly measured magnetic field strengths remains scarce. We observed the 38.3 and 38.5 GHz Class II methanol (CH _3 OH) maser lines toward the high-mass star-forming ...
E. Momjian, A. P. Sarma
doaj   +1 more source

ALMA Detection of Masers and Dasars in the Hydrogen Recombination Lines of the Planetary Nebula Mz3

The Astrophysical Journal
The hydrogen recombination lines H30 α , H40 α , H42 α , H50 β , and H57 γ and the underlying bremsstrahlung continuum emission were detected with ALMA in the bipolar nebula Mz3.
Zulema Abraham, Pedro P. B. Beaklini, Isabel Aleman, Raghvendra Sahai, Albert Zijlstra, Stavros Akras, Denise R. Gonçalves, Toshiya Ueta   +7 more
doaj   +1 more source

A search for water masers toward extrasolar planets

, 2006
Water is the most common triatomic molecule in the universe and the basis of life on Earth. Astrophysical masers have been widely studied in recent years and have been shown to be invaluable probes of the details of the environment in which they are ...
Bastian, Bergin, Bjoraker, Boonman, Brown, Butler, C. Lineweaver, Cernicharo, Cheung, Chyba, Claussen, Dickinson, Elitzur, Engels, Genzel, Lecacheux, Lellouch, Menten, Menten, Pogrebenko, Setiawan, Shoemaker, Takaba, Torrelles, Tsuji, V. Minier, Wallace, Waters, Yates, Young   +29 more
core   +1 more source

Numerical simulation of astrophysical cyclotron-maser emission [PDF]

2013 38th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz), 2013
Numerical simulations have been conducted at the University of Strathclyde to study the spatial growth rate and emission topology of the cyclotron maser instability responsible for auroral magnetospheric radio emission from stars and planets and intense non-thermal radio emission in other astrophysical contexts.
Speirs, D. C., McConville, S. L., Gillespie, K. M., Phelps, A.D.R., Cross, A. W., Ronald, K.   +5 more
openaire   +2 more sources

Frequency Extensions of Auroral Kilometric Radiation: The Key to Unlocking Earth's Radio Response to Substorms

Journal of Geophysical Research: Space Physics, Volume 131, Issue 3, March 2026.
Abstract Auroral kilometric radiation (AKR) provides a sensitive probe of magnetospheric dynamics during substorms. We analyze an extended data set of AKR bursts observed by the WIND spacecraft to investigate how the frequency structure of AKR responds to substorm onset and evolution.
Simon James Walker, Caitríona M. Jackman, Alexandra R. Fogg, Siyuan Wu, James E. Waters   +4 more
wiley   +1 more source

FAST Detection of OH Emission in the Carbon-rich Planetary Nebula NGC 7027

The Astrophysical Journal
We present the first detection of the ground-state OH emission line at 1612 MHz toward the prototypical carbon-rich planetary nebula (PN) NGC 7027, utilizing the newly installed ultrawideband (UWB) receiver of the Five-hundred-meter Aperture Spherical ...
Xu-Jia Ouyang, Yong Zhang, Chuan-Peng Zhang, Peng Jiang, Jun-ichi Nakashima, Xi Chen, Hai-Hua Qiao, Xu-Ying Zhang, Hao-Min Sun, Xiao-Hu Li, Albert Zijlstra   +10 more
doaj   +1 more source

Infrared variability, maser activity, and accretion of massive young stellar objects [PDF]

, 2017
Methanol and water masers indicate young stellar objects. They often exhibit flares, and a fraction shows periodic activity. Several mechanisms might explain this behavior but the lack of concurrent infrared (IR) data complicates to identify the cause ...
Garatti, A. Caratti o, Hodapp, K., Linz, H., Moscadelli, L., Sanna, A., Stecklum, B.   +5 more
core   +2 more sources

Saturation and beaming in astrophysical masers

The Astrophysical Journal, 1985
A 'four-stream' model system of equations that are closely analogous to the equations of radiative transfer in a maser spectral line and are amenable to numerical solution are constructed. This model is used to investigate radiative transfer in asymmetric maser clouds.
C. Alcock, R. R. Ross
openaire   +1 more source

Evidence of an Extended Alfvén Wing System at Enceladus: Cassini's Multi‐Instrument Observations

Journal of Geophysical Research: Space Physics, Volume 131, Issue 2, February 2026.
Abstract We report in situ evidence for Enceladus' Alfvén wing system and its coupling with Saturn's ionosphere, based on multi‐instrument observations from the Cassini spacecraft. Analysis of 36 events, including 13 from non‐flyby paths, confirms the existence of a Main Alfvén Wing (MAW) current system generated at Enceladus, and associated Reflected ...
L. Z. Hadid, T. Chust, J.‐E. Wahlund, M. W. Morooka, E. Roussos, O. Witasse, J. Rabia, D. Pisa, K. Kim, N. J. T. Edberg, A. M. Rymer, L. Lamy, S. Kotsiaros, S. Aizawa, A. Jeandet, R. Modolo, N. André, P. Canu, C. F. Bowers, X. Jia, A. J. Coates, G. H. Jones, A. Parsec‐Wallis, O. Agiwal, M. K. G. Holmberg, Q. Nénon, H. Cao, W. S. Kurth, M. K. Dougherty   +28 more
wiley   +1 more source

Peculiar Spectral Property of Coherent Radio Emission from a Hot Magnetic Star: The Case of an Extreme Oblique Rotator

The Astrophysical Journal, 2023
We report ultra-wideband (0.4–4.0 GHz) observation of coherent radio emission via electron cyclotron maser emission (ECME) produced by the hot magnetic star HD 142990.
Barnali Das, Poonam Chandra
doaj   +1 more source