中文
相关论文

相关论文: The intra-hour variable quasar J1819$+$3845: 13-ye…

200 篇论文

A new pulsating X-ray source, AX J183220-0840, with a 1549.1-s period was discovered at R.A.= 18h32m20s and Dec.=-8d40'30'' (J2000, uncertainty=0.6degree) during an ASCA observation on the Galactic plane. The source was observed two times,…

天体物理学 · 物理学 2009-10-31 M. Sugizaki , K. Kinugasa , K. Matsuzaki , Y. Terada , S. Yamauchi , J. Yokogawa

The effect of interplanetary plasma on pulsed pulsar radiation passing through is considered. The pulses of two rotating radio transients (J0609+16, J1132+25) and a pulsar (B0320+39) detected on the Large Phased Array (Pushchino…

高能天体物理现象 · 物理学 2023-05-24 S. A. Tyul'bashev , I. V. Chashei , M. A. Kitaeva

We have studied the rapid X-ray variability of three extragalactic TeV gamma-ray sources; Mrk 421, Mrk 501 and PKS 2155-304. Analyzing the X-ray light curves obtained from ASCA and/or RXTE observations between 1993 and 1998, we have…

In our previous paper (Popov et al. (2016)) we investigated properties of the ionized interstellar medium in the direction of three distant pulsars: B1641-45, B1749-28, and B1933+16. We found that uniformly distributed scattering material…

星系天体物理 · 物理学 2018-08-15 E. N. Fadeev

The scintillation of pulsars reveals small-scale structure of the interstellar medium. A powerful technique for characterizing the scintillating structures (screens) combines analysis of scintillation arcs and very long baseline…

高能天体物理现象 · 物理学 2025-10-21 Ashley M. Stock , Fardin Syed , Marten H. van Kerkwijk , Rebecca Lin , Franz Kirsten , Ue-Li Pen

The dust shell around the evolved star HD 179821 has been detected in scattered light in near-IR imaging polarimetry observations. Here, we subtract the contribution of the unpolarized stellar light to obtain an intrinsic linear…

天体物理学 · 物理学 2009-11-07 T. M. Gledhill , M. Takami

We carried out observations of pulsar PSR B1919+21 at 324 MHz to study the distribution of interstellar plasma in the direction of this pulsar. We used the RadioAstron (RA) space radiotelescope together with two ground telescopes:…

太阳与恒星天体物理 · 物理学 2017-05-10 V. I. Shishov , T. V. Smirnova , C. R. Gwinn , A. S. Andrianov , M. V. Popov , A. G. Rudnitskiy , V. A. Soglasnov

Radio images of the Galactic Center supermassive black hole, Sagittarius A* (Sgr A*), are dominated by interstellar scattering. Previous studies of Sgr A* have adopted an anisotropic Gaussian model for both the intrinsic source and the…

Extreme Scattering Events (ESEs) are dramatic variations of the flux density at Gigahertz frequencies caused by ray path distortions within an isolated inhomogeneity ("plasma lens") in the interstellar medium. These events are characterized…

天体物理学 · 物理学 2009-11-07 G. Cimò , T. Beckert , T. P. Krichbaum , L. Fuhrmann , A. Kraus , A. Witzel , J. A. Zensus

The aim of our work was to study the spatial structure of inhomogeneities of interstellar plasma in the directions of five pulsars: B0823+26, B0834+06, B1237+25, B1929+10, and B2016+28. Observations of these pulsars were made with…

Blazar emission is dominated by non-thermal radiation from a relativistic jet pointing toward us, therefore undergoing Doppler beaming. This is responsible for flux enhancement and contraction of the variability time scales, so that most…

高能天体物理现象 · 物理学 2019-08-13 C. M. Raiteri , M. Villata

High-redshift blazars are one of the most powerful monsters in the universe and $\gamma$-ray variability carries crucial information of their relativistic jets. In this work we present results of the first systematical temporal analysis of…

高能天体物理现象 · 物理学 2018-02-14 Shang Li , Zi-Qing Xia , Yun-Feng Liang , Neng-Hui Liao , Yi-Zhong Fan

We are undertaking a large-scale, Micro-Arcsecond Scintillation-Induced Variability (MASIV) survey of the northern sky, Dec > 0 deg, at 4.9 GHz with the VLA. Our objective is to construct a sample of 100 to 150 scintillating extragalactic…

天体物理学 · 物理学 2008-11-26 J. Lovell , D. Jauncey , H. Bignall , L. Kedziora-Chudczer , J-P. Macquart , B. Rickett , A. Tzioumis

The variability of quasars across multiple wavelengths is a useful probe of physical conditions in active galactic nuclei. In particular, variable accretion rates, instabilities, and reverberation effects in the accretion disk of a…

星系天体物理 · 物理学 2020-05-13 Chengcheng Xin , Maria Charisi , Zoltán Haiman , David Schiminovich

The flat spectrum radio quasar PKS 1510-089 is one of the most active blazars in $\gamma$-rays, exhibiting phases of very high activity. This study investigates its variability over a decade across a wide range of wavelengths, from radio to…

高能天体物理现象 · 物理学 2024-10-24 Alfredo Amador-Portes , Abigail García-Pérez , Vahram Chavushyan , Victor M. Patiño-Álvarez

The double pulsar system PSR~J0737$-$3039A/B has enabled some of the most precise tests of strong-field gravity to date. Here, we present a scintillation analysis of the system based on an 18-month observation campaign with the MeerKAT…

We examine the relationship between source position stability and astrophysical properties of radio-loud quasars making up the International Celestial Reference Frame. Understanding this relationship is important for improving quasar…

宇宙学与河外天体物理 · 物理学 2015-06-16 Stanislav Shabala , Jonathan Rogers , Jamie McCallum , Oleg Titov , Jay Blanchard , Jim Lovell , Christopher Watson

We have observed profound variability in the radio flux density of the quasar PKS 0405-385 on timescales of less than an hour; this is unprecedented amongst extragalactic sources. If intrinsic to the source, these variations would imply a…

We explore the variability and cross-frequency correlation of the flux density and polarization of the blazar OJ287, using imaging at 43 GHz with the Very Long Baseline Array, as well as optical and near-infrared polarimetry. The…

Characterization of self-consistent laser-plasma evolutions serves as a fundamental issue in the field of relativistic laser-plasma interactions. In this paper, we present an analysis framework for description of these evolutions during…

等离子体物理 · 物理学 2019-06-11 J. Yazdanpanah
‹ 上一页 1 8 9 10 下一页 ›