English
Related papers

Related papers: Polarized, variable radio emission from the scallo…

200 papers

We report $I$-band photometric observations of the radio-detected M9.5 dwarf BRI 0021-0214, obtained with the Galway Ultra Fast Imager (GUFI) on the 1.8m Vatican Advanced Technology Telescope VATT at Mt. Graham International Observatory,…

Solar and Stellar Astrophysics · Physics 2022-11-03 S. Dulaimi , A. Golden , R. P. Boyle , R. F. Butler

Violent multi-wavelength variabilities are observed in gamma-ray-selected blazars. We present an analysis of long-term light curves for eight bright blazars to explore the co-variation pattern in the gamma-ray and radio bands. We extract…

High Energy Astrophysical Phenomena · Physics 2020-05-27 Hai-Ming Zhang , Zhen-Jie Wang , Jin Zhang , Ting-Feng Yi , Liang Chen , Rui-Jing Lu , En-Wei Liang

We present the analysis results of an eclipsing cataclysmic variable (CV) V729 Sgr, based on our observations and AAVSO data. Some outburst parameters were determined such as outburst amplitude ($A_{n}$) and recurrence time ($T_{n}$), and…

Astrophysics of Galaxies · Physics 2018-01-10 Han Zhongtao , Qian Shengbang , Lajús , E. Fernández , Voloshina Irina , Zhu Liying

In 2005, Palla & Baraffe proposed that brown dwarfs (BDs) and very low mass stars (VLMSs; <0.1 solar masses) may be unstable to radial oscillations during the pre-main-sequence deuterium burning phase. With associated periods of 1-4 hours,…

Solar and Stellar Astrophysics · Physics 2015-06-23 Ann Marie Cody , Lynne A. Hillenbrand

Fast radio bursts (FRBs) with unknown origin emit a huge luminosity (about 1 Jy at 1 GHz) with a duration of milliseconds or less at extragalactic distances estimated from their large dispersion measure (DM). We propose herein a scenario…

High Energy Astrophysical Phenomena · Physics 2018-11-19 Xiang Liu

The OVRO 40-m telescope has been monitoring the 15 GHz radio flux density of over 1200 blazars since 2008. The 15 GHz light curve of the flat spectrum radio quasar J1359+4011 shows a strong and persistent quasi-periodic oscillation. The…

High Energy Astrophysical Phenomena · Physics 2015-06-17 O. G. King , T. Hovatta , W. Max-Moerbeck , D. L. Meier , T. J. Pearson , A. C. S. Readhead , R. Reeves , J. L. Richards , M. C. Shepherd

Thorstensen (2020) recently argued that the cataclysmic variable (CV) LAMOST J024048.51+195226.9 may be a twin to the unique magnetic propeller system AE Aqr. If this is the case, two predictions are that it should display a short period…

Blazars are a subclass of radio-loud active galactic nuclei (AGNs), where the jet is aligned close to the line of sight. Blazars emission is dominated by non-thermal processes, where Doppler boosted radiation originates from a relativistic…

High Energy Astrophysical Phenomena · Physics 2021-08-19 Jakub Juryšek , Vitalii Sliusar , Dimitri Moulin , Roland Walter

We present the results of a two and a half year optical photometric monitoring programme covering 16 AM CVn binaries using the Liverpool Telescope on La Palma. We detected outbursts in seven systems, one of which (SDSS J0129) was seen in…

Astrophysics of Galaxies · Physics 2015-05-30 Gavin Ramsay , Thomas Barclay , Danny Steeghs , Peter J. Wheatley , Pasi Hakala , Iwona Kotko , Simon Rosen

Solar radio bursts exhibit complex fine structures that reveal intricate coronal plasma dynamics. Here, we report detection of spike-like repeating burst pairs, characterized by two short-lived (0.1-2 s), narrowband components separated by…

Solar and Stellar Astrophysics · Physics 2026-05-28 Suli Ma , Eduard P. Kontar , Daniel L. Clarkson , Huadong Chen , Yihua Yan

PSR B1259-63 is a 48 ms pulsar in a highly eccentric 3.4 year orbit around the young massive star LS 2883. During the periastron passage the system displays transient non-thermal unpulsed emission from radio to very high energy gamma rays.…

High Energy Astrophysical Phenomena · Physics 2011-09-02 J. Moldon , S. Johnston , M. Ribo , J. M. Paredes , A. T. Deller

Characterizing the distribution of flare properties and occurrence rates is important for understanding habitability of M dwarf exoplanets. The GALEX space telescope observed the GJ 65 system, composed of the active, flaring M stars BL Cet…

Solar and Stellar Astrophysics · Physics 2022-03-30 Scott W. Fleming , Chase Million , Rachel A. Osten , Dmitrii Y. Kolotkov , C. E. Brasseur

We report on observations of the {\gamma}-ray and optical photopolarimetric behavior of the radio-loud, narrow line type-1 Seyfert galaxy PMN J0948+0022 over a twenty seven month period. As this object has recently been suggested to…

High Energy Astrophysical Phenomena · Physics 2015-06-12 Joseph R. Eggen , H. Richard Miller , Jeremy D. Maune

We present spectroscopy and orbital periods Porb for 30 apparently non-magnetic cataclysmic binaries with periods below about 3 hours, nearly all of which are dwarf novae, mostly of the SU Ursae Majoris subclass. We then turn to the…

Solar and Stellar Astrophysics · Physics 2020-06-17 John R. Thorstensen

Fast radio bursts (FRBs) are bright, coherent, short-duration radio transients of as-yet unknown extragalactic origin. FRBs exhibit a wide variety of spectral, temporal and polarimetric properties, which can unveil clues into their emission…

High Energy Astrophysical Phenomena · Physics 2021-01-06 K. Nimmo , J. W. T. Hessels , A. Keimpema , A. M. Archibald , J. M. Cordes , R. Karuppusamy , F. Kirsten , D. Z. Li , B. Marcote , Z. Paragi

Using the Hamilton Echelle Spectrograph at Lick Observatory, we have obtained precise radial velocities (RVs) of a sample of 373 G- and K-giant stars over more than 12 years, leading to the discovery of several single and multiple planetary…

Time-variable polarization is an extremely valuable observational tool to probe the dynamical physical conditions of blazar jets. Since 2008, we have been monitoring the flux and linear polarization of a sample of gamma-ray bright blazars…

High Energy Astrophysical Phenomena · Physics 2021-05-04 Alan P. Marscher , Svetlana G. Jorstad

Blazars are highly variable active galactic nuclei which emit radiation at all wavelengths from radio to gamma-rays. Polarized radiation from blazars is one key piece of evidence for synchrotron radiation at low energies and it also varies…

We present results from a search for radio emission in 77 stellar systems hosting 140 exoplanets, predominantly within 17.5 pc using the Very Large Array (VLA) at $4-8$ GHz. This is the largest and most sensitive search to date for radio…

Earth and Planetary Astrophysics · Physics 2024-04-29 Kevin N. Ortiz Ceballos , Yvette Cendes , Edo Berger , Peter K. G. Williams

High sensitivity searches of globular clusters (GC) for radio pulsars by improved pulsar search algorithms and sustained pulsar timing observations have so far yielded some 140 pulsars in more than two dozen GCs. The observed distribution…

Solar and Stellar Astrophysics · Physics 2011-02-11 Manjari Bagchi , Alak Ray