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相关论文: A VLA search for 5 GHz radio transients and variab…

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(abridged) Recently, a new class of radio transients in the 5-GHz band was detected by Bower et al. We present new deep near-Infrared (IR) observations of the field containing these transients, and find no counterparts down to a limiting…

高能天体物理现象 · 物理学 2014-11-20 E. O. Ofek , B. Breslauer , A. Gal-Yam , D. Frail , M. M. Kasliwal , S. R. Kulkarni , E. Waxman

Using three epochs of VLA observations of the Galactic Plane in the first quadrant taken ~15 years apart, we have conducted a search for a population of variable Galactic radio emitters in the flux density range 1-100 mJy at 6 cm. We find…

星系天体物理 · 物理学 2015-05-18 Robert H. Becker , David J. Helfand , Richard L. White , Deanne D. Proctor

We present a survey for transient and variable sources, on timescales from 28 seconds to $\sim$1 year, using the Murchison Widefield Array (MWA) at 182 MHz. Down to a detection threshold of 0.285 Jy, no transient candidates were identified,…

A wide range of phenomena, from explosive transients to active galactic nuclei, exhibit variability at radio wavelengths on timescales of a few years. Characterizing the rate and scale of variability in the radio sky can provide keen…

星系天体物理 · 物理学 2026-05-21 Yjan A. Gordon , Peter S. Ferguson , Michael N. Martinez , Eric J. Hooper

We present a pilot search for variable and transient sources at 1.4 GHz with the Australian Square Kilometre Array Pathfinder (ASKAP). The search was performed in a 30 deg$^{2}$ area centred on the NGC 7232 galaxy group over 8 epochs and…

We report on the results of a search for radio transients between 115 and 190\,MHz with the LOw-Frequency ARray (LOFAR). Four fields have been monitored with cadences between 15 minutes and several months. A total of 151 images were…

We report multiple epoch VLA/JVLA observations of 89 northern hemisphere sources, most with 37\,GHz flux density > 1 Jy, observed at 4.8, 8.5, 33.5, and 43.3 GHz. The high frequency selection leads to a predominantly flat spectrum sample,…

宇宙学与河外天体物理 · 物理学 2013-01-21 Noah Kurinsky , Anna Sajina , Bruce Partridge , Steve Myers , Xi Chen , Marcos López-Caniego

We present a search for transient radio sources on timescales of 2 to 9 yr at 150 MHz. This search is conducted by comparing the first Alternative Data Release of the TIFR GMRT Sky Survey (TGSS ADR1) and the second data release of the LOFAR…

In the time domain, the radio sky in particular along the Galactic plane direction may vary significantly because of various energetic activities associated with stars, stellar and supermassive black holes. Using multi-epoch Very Large…

高能天体物理现象 · 物理学 2022-01-12 Jun Yang , Yongjun Chen , Leonid I. Gurvits , Zsolt Paragi , Aiyuan Yang , Xiaolong Yang , Zhiqiang Shen

A sample of 123 radio sources that exhibit significant variations at 1.4 GHz on a seven year base-line has been created using FIRST VLA B-array data from 1995 and 2002 on a strip at dec=0 near the south Galactic cap. This sample spans the…

天体物理学 · 物理学 2009-11-10 W. H. de Vries , R. H. Becker , R. L. White , D. J. Helfand

A new generation of radio telescopes with excellent sensitivity, instantaneous {\it uv} coverage, and large fields of view, are providing unprecedented opportunities for performing commensal transient searches. Here we present such a…

高能天体物理现象 · 物理学 2023-09-18 S. I. Chastain , A. J. van der Horst , A. Rowlinson , L. Rhodes , A. Andersson , R. Diretse , R. P. Fender , P. A. Woudt

Galactic radio transients (GRTs) are mysterious short-lived (~days to months) radio transients that are quiet at all other wavelengths. Until now, roughly half a dozen such sources have been reported, predominantly towards the Galactic…

We present Very Large Array (VLA) observations at 1.4 GHz and 5 GHz of a sample of 12 Quasi-stellar Objects (QSOs) at z = 3.99 to 4.46. The sources were selected as the brightest sources at 250 GHz from the recent survey of Omont et al.…

天体物理学 · 物理学 2009-11-06 C. L. Carilli , F. Bertoldi , A. Omont , P. Cox , R. G. McMahon , K. G. Isaak

A comprehensive search for variable and transient radio sources has been conducted using ~55,000 snapshot images of the FIRST survey. We present an analysis leading to the discovery of 1,627 variable and transient objects down to mJy levels…

宇宙学与河外天体物理 · 物理学 2015-05-30 Nithyanandan Thyagarajan , David J. Helfand , Richard L. White , Robert H. Becker

We present results from a radio survey for variable and transient sources on 15-min timescales, using the Australian SKA Pathfinder (ASKAP) pilot surveys. The pilot surveys consist of 505 h of observations conducted at around 1 GHz…

The Very Large Array (VLA) has been used in C-configuration to map an area \~0.3 square degrees at 1.4 GHz with 5sigma sensitivities of 0.305, 0.325, 0.380 and 0.450 mJy/beam over four equal subareas. Radio properties are presented for 62…

天体物理学 · 物理学 2009-10-31 Frank J. Masci , J. J. Condon , T. A. Barlow , C. J. Lonsdale , D. L. Shupe , O. Pevunova , F. Fang , R. Cutri

We present multi-frequency and high-resolution studies of a sample of 24 radio transients sources discovered by comparing the NRAO VLA Sky Survey (NVSS) and Very Large Array Sky Survey (VLASS) surveys. All of them are characterized by a…

As part of an on-going study of radio transients in Epoch 1 (2017-2019) of the Very Large Array Sky Survey (VLASS), we have discovered a sample of 0.2<z<3.2 active galactic nuclei (AGN) selected in the optical/infrared that have recently…

The origin of radio emission in the majority of Active Galactic Nuclei (AGN) is still poorly understood. Various competing mechanisms are likely involved in the production of radio emission and precise diagnostic tools are needed to…

We present high resolution (arcsecond or better) observations made with the Karl G. Jansky Very Large Array of 123 radio-loud quasars with redshifts in the range $2.5 \leq z \leq 5.28$ that form a complete flux limited sample ($\geq 70$ mJy…

星系天体物理 · 物理学 2014-06-19 Doug B. Gobeille , John F. C. Wardle , C. C. Cheung