Results 31 to 40 of about 173 (158)

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

Low Frequency Extensions of Cyclotron Maser Instability‐Generated Radio Emission: A Statistical View From Cassini at Saturn

Journal of Geophysical Research: Space Physics, Volume 131, Issue 8, August 2026.
Abstract The Cassini spacecraft spent 13 years orbiting Saturn, quasi‐continuously measuring Saturn's radio emissions. One of the key elements of the radio spectrum at Saturn is the Saturn Kilometric Radiation (SKR), and several studies have been written on events called Low Frequency Extensions (LFEs) which represent strong, continuous extensions of ...
C. M. Jackman, A. R. Fogg, S. W. H. Cowley, G. Provan, H. Adamski, N. M. Besch, D. M. Hollman, S. Walker, M. J. Rutala, L. Lamy, C. K. Louis, E. P. O’Dwyer   +11 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

Earthward Propagated Auroral Kilometric Radiation: Observations From Polar

Geophysical Research Letters, Volume 53, Issue 12, 28 June 2026.
Abstract Auroral Kilometric Radiation (AKR), the strongest natural radio emission from Earth's magnetosphere, has been primarily observed in space. It is generally understood to propagate anti‐Earthward and be detected at large radial distances, while Earthward‐directed waves are thought to be blocked by the ionosphere. Surprisingly, AKR‐like emissions
Olha Melnychenko, Siyuan Wu, Daniel K. Whiter, Baptiste Cecconi, Claire Baskvetich   +4 more
wiley   +1 more source

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

On the Detection of Low‐Frequency Planetary Radio Emission With an Orbiting Interferometer

Radio Science, Volume 61, Issue 6, June 2026.
Abstract The magnetized planets of the outer Solar System produce kilometric radio emissions at very low frequencies (<1 ${< } 1\,$MHz). They reveal the planetary magnetic dynamics and their interaction with the solar wind. Those radio emissions can also serve as a proxy for interplanetary space weather monitoring.
E. Rouillé, B. Cecconi, B. Segret, J. N. Girard, A. Loh   +4 more
wiley   +1 more source

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

Frequency Standard Contributions to Limitations on the Signal‐to‐Noise Ratio in Very Long Baseline Interferometric Observations

Radio Science, Volume 61, Issue 6, June 2026.
Abstract Since its observation in 2019, the first image of a super‐massive black hole using Very Long Baseline Interferometry (VLBI) with an Earth‐scale baseline has generated much scientific and public interest. Work is now underway to extend the baseline into space to obtain higher image resolution.
E. A. Burt, T. A. Ely, G. C. Bower, T. J. W. Lazio, M. Anderson, S. Hernandez   +5 more
wiley   +1 more source

The electron–cyclotron maser for astrophysical application [PDF]

The Astronomy and Astrophysics Review, 2006
The electron–cyclotron maser is a process that generates coherent radiation from plasma. In the last two decades, it has gained increasing attention as a dominant mechanism of producing high-power radiation in natural high-temperature magnetized plasmas.
openaire   +2 more sources

New Constraints on the Jovian Narrowband Radio Components From Juno/Waves Observations and 3D Geometrical Simulations

Journal of Geophysical Research: Space Physics, Volume 131, Issue 4, April 2026.
Abstract Measurements of Waves instrument onboard the Juno spacecraft suggest that narrowband kilometric radiation (nKOM; 20–141 kHz) and narrowband low‐frequency radiation (nLF; 5–70 kHz) are generated within the plasma near the Io plasma torus (IPT) in low‐latitude regions.
A. Boudouma, P. Zarka, C. K. Louis, M. Imai, C. Briand   +4 more
wiley   +1 more source