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We detect radio emission in an additional two epochs of the ultracool dwarf binary LP 349- 25, finding that the observed emission is broadband and steady on timescales between 10s and 10.7 hours, as well as on timescales of 0.6 and 1.6…

Solar and Stellar Astrophysics · Physics 2009-07-24 R. A. Osten , N. Phan-Bao , S. L. Hawley , I. Neill Reid , R. Ojha

A new acousto-optic radio spectrometer has observed the 1 - 2 GHz radio emission of solar flares with unprecedented sensitivity. The number of detected decimeter type III bursts is greatly enhanced compared to observations by conventional…

Astrophysics · Physics 2009-10-31 Arnold O. Benz , Peter Messmer , Christian Monstein

We are leading a comprehensive multi-waveband monitoring program of 34 gamma-ray bright blazars designed to locate the emission regions of blazars from radio to gamma-ray frequencies. The "maps" are anchored by sequences of images in both…

High Energy Astrophysical Phenomena · Physics 2015-05-20 Alan Marscher , Svetlana G. Jorstad , Valeri M. Larionov , Margo F. Aller , Anne Lahteenmaki

We present multiwaveband observations of a well selected sample of 28 quasars and two radio galaxies with flat radio spectra and strong millimeter wave emission (referred to here as FSRQ's). The observations include multifrequency VLBI…

Utilizing the all-sky imaging capabilities of the LWA1 radio telescope along with a host of all-sky optical cameras, we have now observed 44 optical meteor counterparts to radio afterglows. Combining these observations we have determined…

Earth and Planetary Astrophysics · Physics 2016-09-16 K. S. Obenberger , J. M. Holmes , J. D. Dowell , F. K. Schinzel , K. Stovall , E. K. Sutton , G. B. Taylor

LWA1 is a new radio telescope operating in the frequency range 10-88 MHz, located in central New Mexico. The telescope consists of 258 pairs of dipole-type antennas whose outputs are individually digitized and formed into beams.…

Instrumentation and Methods for Astrophysics · Physics 2015-06-04 S. W. Ellingson , G. B. Taylor , J. Craig , J. Hartman , J. Dowell , C. N. Wolfe , T. E. Clarke , B. C. Hicks , N. E. Kassim , P. S. Ray , L. J. Rickard , F. K. Schinzel , K. W. Weiler

The multi-Needle Langmuir Probe collects an electron current through four fixed-bias cylindrical copper needles. This allows for an extremely high sampling frequency, with plasma properties being inferred through polynomial fitting in the…

Space Physics · Physics 2025-06-11 Magnus F Ivarsen , Lasse B N Clausen , Yaqi Jin , Jaeheung Park

Fast radio bursts (FRBs) are millisecond-duration, bright radio signals (fluence $\mathrm{0.1 - 100\,Jy\,ms}$) emitted from extragalactic sources of unknown physical origin. The recent CHIME/FRB and STARE2 detection of an extremely bright…

High Energy Astrophysical Phenomena · Physics 2020-11-18 F. Kirsten , M. Snelders , M. Jenkins , K. Nimmo , J. van den Eijnden , J. Hessels , M. Gawronski , J. Yang

The behaviour of the pulsar spectrum at high radio frequencies can provide decisive information about the nature of the radio emission mechanism. We report recent observations of a selected sample of pulsars at lambda=9mm (32 GHz) with the…

Astrophysics · Physics 2009-11-13 O. Loehmer , A. Jessner , M. Kramer , R. Wielebinksi , O. Maron

Magnetars younger than one century are expected to be hyper active. Besides winds powered by rotation they generate frequent magnetic flares, which launch powerful blast waves into the wind. These internal shocks act as masers producing…

High Energy Astrophysical Phenomena · Physics 2020-07-01 Andrei M. Beloborodov

We present the analysis of the atmospheric trajectory and orbital data of four bright bolides observed over Spain, one of which is a potential meteorite dropping event. Their absolute magnitude ranges from -10 to -11. Two of these are of…

Earth and Planetary Astrophysics · Physics 2015-06-16 J. M. Madiedo , J. M. Trigo-Rodriguez , J. L. Ortiz , A. J. Castro-Tirado , S. Pastor , J. A. de los Reyes , J. Cabrera-Cano

The Long Wavelength Array (LWA) will be a new multi-purpose radio telescope operating in the frequency range 10-88 MHz. Scientific programs include pulsars, supernova remnants, general transient searches, radio recombination lines, solar…

Instrumentation and Methods for Astrophysics · Physics 2012-06-11 G. B. Taylor , The LWA Collaboration

High resolution millimeter-wave and near-infrared observations of the supernova remnants W28 and W44 reveal extensive shocked molecular gas where supernova blast waves are propagating into giant molecular clouds. New CO observations were…

Astrophysics · Physics 2014-10-13 William T. reach , Jeonghee Rho , T. H. Jarrett

Three-millimeter-wavelength spectra of a number of nearby galaxies have been obtained at the Five College Radio Astronomy Observatory (FCRAO) using a new, very broadband receiver. This instrument, which we call the Redshift Search Receiver,…

Our high time resolution observations of individual pulses from the Crab pulsar show that both the time and frequency signatures of the interpulse are distinctly different from those of the main pulse. Main pulses can occasionally be…

Astrophysics · Physics 2009-11-13 T. H. Hankins , J. A. Eilek

We briefly review main observational properties of fast radio bursts (FRBs) and discuss two most popular hypothesis for the explanation of these enigmatic intense millisecond radio flashes. FRBs most probably originate on extragalactic…

High Energy Astrophysical Phenomena · Physics 2018-08-08 S. B. Popov , K. A. Postnov , M. S. Pshirkov

In the highly dynamic chromosphere, there exist many kinds of small-scale activities, such as spicules, surges, and Ellerman bombs. Here, we report the discovery of a new phenomenon in the chromosphere observed with the New Vacuum Solar…

Solar and Stellar Astrophysics · Physics 2019-08-07 Shuhong Yang , Jun Zhang , Xiaohong Li , Zhong Liu , Yongyuan Xiang

Activities in M dwarfs show spectroscopic variability over various time scales ranging from a few seconds to several hours. The time scales of such variability can be related to internal dynamics of M dwarfs like magnetic activity,…

Solar and Stellar Astrophysics · Physics 2023-02-06 Vipin Kumar , A. S. Rajpurohit , Mudit K. Srivastava

We report multi-wavelength observations of four solar flares on 2014 July 07. We firstly select these flares according to the soft X-ray (SXR) and extreme ultraviolet (EUV) emissions recorded by the Extreme Ultraviolet Variability…

Solar and Stellar Astrophysics · Physics 2021-05-05 Dong Li , Alexander Warmuth , Lei Lu , Zongjun Ning

We report discovery of several energetic radio bursts at 34 MHz, using the Gauribidanur radio telescope. The radio bursts exhibit two important properties associated with the propagation of astronomical signals through the interstellar…

Solar and Stellar Astrophysics · Physics 2015-12-23 Yogesh Maan