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Related papers: A compact steep spectrum radio source in NGC1977

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We report the discovery of gamma-ray pulsations (> 0.1 GeV) from the young radio and X-ray pulsar PSR J0205+6449 located in the Galactic supernova remnant 3C 58. Data in the gamma-ray band were acquired by the Large Area Telescope aboard…

High Energy Astrophysical Phenomena · Physics 2009-07-09 Fermi LAT collaboration , Fermi Pulsar Timing Consortium

Transient astronomical sources are typically powered by compact objects and usually signify highly explosive or dynamic events. While radio astronomy has an impressive record of obtaining high time resolution observations, usually it is…

Astrophysics · Physics 2009-11-10 S. D. Hyman , T. J. W. Lazio , N. E. Kassim , P. S. Ray , C. B. Markwardt , F. Yusef-Zadeh

We have studied the Be/X-ray binary (BeXRB) pulsar eRASSU J050810.4-660653 recently discovered in the Large Magellanic Cloud (LMC). Timing and spectral features of the source have been discussed in detail using NuSTAR \& XMM-Newton…

High Energy Astrophysical Phenomena · Physics 2022-11-30 Manoj Ghising , Mohammed Tobrej , Ruchi Tamang , Binay Rai , Bikash Chandra Paul

We describe PSR J1926-0652, a pulsar recently discovered with the Five-hundred-meter Aperture Spherical radio Telescope (FAST). Using sensitive single-pulse detections from FAST and long-term timing observations from the Parkes 64-m radio…

We report on the detection of optically thick free-free radio sources in the galaxies M33, NGC 253, and NGC 6946 using data in the literature. We interpret these sources as being young, embedded star birth regions, which are likely to be…

Astrophysics · Physics 2009-11-06 Kelsey E. Johnson , Chip Kobulnicky , Phil Massey , Peter Conti

The Fermi Large Area Telescope gamma-ray source 3FGL J2039.6$-$5618 contains a periodic optical and X-ray source that was predicted to be a "redback" millisecond pulsar (MSP) binary system. However, the conclusive identification required…

The southern Galactic high mass star-forming region, G351.6-1.3, is a HII region-molecular cloud complex with a luminosity of 2.0 x 10^5 L_sun, located at a distance of 2.4 kpc. In this paper, we focus on the investigation of the associated…

Astrophysics of Galaxies · Physics 2015-06-19 S. Vig , S. K. Ghosh , D. K. Ojha , R. P. Verma , M. Tamura

ASCA observed the central region of the Small Magellanic Cloud, and found a hard X-ray source, AX J0051-733, at the position of the ROSAT source RX J0050.8-7316, which has an optical counterpart of a Be star. Coherent X-ray pulsations of…

Astrophysics · Physics 2015-06-24 Kensuke Imanishi , Jun Yokogawa , Masahiro Tsujimoto , Katsuji Koyama

The large number of ongoing surveys for pulsars and transients at various radio observatories is motivated by the science obtained from these sources. Timing and polarisation analysis of relativistic binaries can place strong constraints on…

Several sources of repeating coherent bursts of radio emission with periods of many minutes have now been reported in the literature. These "ultra-long period" (ULP) sources have no clear multi-wavelength counterparts and challenge…

In Torne et al. (2015), we showed detections of SGR J1745-2900 up to 225 GHz (1.33 mm); at that time the highest radio frequency detection of pulsar emission. In this work, we present the results of new observations of the same magnetar…

High Energy Astrophysical Phenomena · Physics 2016-12-14 P. Torne , G. Desvignes , R. P. Eatough , R. Karuppusamy , G. Paubert , M. Kramer , I. Cognard , D. J. Champion , L. G. Spitler

Context. The majority of bright extragalactic gamma-ray sources are blazars. Only a few radio galaxies have been detected by Fermi/LAT. Recently, the GHz-peaked spectrum source PKS 1718-649 was confirmed to be gamma-ray bright, providing…

High Energy Astrophysical Phenomena · Physics 2016-09-28 C. Müller , P. R. Burd , R. Schulz , R. Coppejans , H. Falcke , H. Intema , M. Kadler , F. Krauß , R. Ojha

We present radio observations of the most slowly rotating known radio pulsar PSR J0250+5854. With a 23.5 s period, it is close, or even beyond, the $P$-$\dot{P}$ diagram region thought to be occupied by active pulsars. The simultaneous…

Compact, steep-spectrum radio sources are key tracers of exotic astrophysical objects such as pulsars and high-redshift radio galaxies. All-sky radio surveys at different frequencies, like the TIFR-GMRT Sky Survey (TGSS) and the NRAO VLA…

Astrophysics of Galaxies · Physics 2026-04-07 Rajat Shinde , Yogesh Maan , Apurba Bera

We observed with the VLBA at 2.3 and 8.6 GHz a complete flux-density limited sample of 482 radio sources with declination >+75 degrees brighter than 200 mJy at 1.4 GHz drawn from the NVSS catalog. 34% of the sources show parsec-scale…

Astrophysics of Galaxies · Physics 2021-02-01 Alexander V. Popkov , Yuri Y. Kovalev , Leonid Y. Petrov , Yuri A. Kovalev

We report on the discovery of a transient X-ray pulsars, located in the Small Magellanic Cloud, with a pulse period of 292 s. A series of Chandra pointings fortuitously recorded in 2010 April-May the occurrence of a two-weeks-long outburst,…

High Energy Astrophysical Phenomena · Physics 2013-08-06 P. Esposito , G. L. Israel , L. Sidoli , G. A. Rodríguez Castillo , N. Masetti , P. D'Avanzo , S. Campana

We report the serendipitous discovery of an extremely intermittent radio pulsar, PSR J1710-3452, with a relatively long spin period of 10.4 s. The object was discovered through the detection of 97 bright radio pulses in only one out of 66…

We present optical spectroscopy of 62 objects selected from several samples of ultra steep spectrum (USS) radio sources. 46 of these are from our primary catalog, consisting of 669 sources with radio spectral indices alpha < -1.30 (S_nu ~…

Recent observations have revealed rare, previously unknown flashes of cosmic radio waves lasting from milliseconds to minutes, and with periodicity of minutes to an hour. These transient radio signals must originate from sources in the…

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