搜索结果: 1-15 共查到“天文学 blazar”相关记录15条 . 查询时间(0.287 秒)
The supersharp radio "vision" of the U.S. National Science Foundation's Very Long Baseline Array has revealed previously unseen details in a jet of material ejected at three-quarters the speed of...
中国科学院上海天文台发现Blazar天体喷流的长期视向内运动
中国科学院上海天文台 Blazar天体 运动
2015/5/29
活动星系核，即活动星系的核心。普遍认为普通星系与活动星系的中心都存在质量在百万个太阳质量以上的大质量黑洞，两者的差异主要是普通星系的中心黑洞周围并没有太多物质供它消耗，所以普通星系中心的发光强度远低于活动星系。喷流是活动星系核的重要组成部分，是自中心超大质量黑洞处激发的运动速度接近光速的相对论性等离子体流。喷流的尺度可达数百万秒差距（1秒差距=3.26光年，1光年=94605亿千米）。根据活动星系...
活动星系核，即活动星系的核心。普遍认为普通星系与活动星系的中心都存在质量在百万个太阳质量以上的大质量黑洞，两者的差异主要是普通星系的中心黑洞周围并没有太多物质供它消耗，所以普通星系中心的发光强度远低于活动星系。喷流是活动星系核的重要组成部分，是自中心超大质量黑洞处激发的运动速度接近光速的相对论性等离子体流。喷流的尺度可达数百万秒差距（1秒差距=3.26光年，1光年=94605亿千米）。根据活动星系...
The Gamma-Ray Blazar PKS 0208-512, a Multi-Wavelength Investigation
Gamma-Ray Blazar PKS 0208-512 Multi-Wavelength Investigation
2012/2/23
The gamma-ray blazar PKS 0208-512 has shown strong periods of flaring, at all frequencies from radio to gamma-ray. This has led to its inclusion in the TANAMI project, which tracks the jets of souther...
The contribution from blazar cascade emission to the extragalactic gamma-ray background: What a role does the extragalactic magnetic field play?
diffuse radiation galaxies active gamma rays general
2012/2/21
We estimate the contribution to the extragalactic gamma-ray background (EGRB) from both intrinsic and cascade emissions produced by blazars using a simple semi- analysis method for two models of the b...
From the Blazar Sequence to the Blazar Envelope: Revisiting the Relativistic Jet Dichotomy in Radio-loud AGN
Blazar Envelope Revisiting Relativistic Jet Dichotomy Radio-loud AGN
2011/10/21
We revisit the concept of a blazar sequence that relates the synchrotron peak frequency ({\nu}peak) in blazars with synchrotron peak luminosity (Lpeak, in {\nu}L{\nu}) using a large sample of radio-lo...
The Lyman-alpha forest in a blazar-heated Universe
cosmology: theory { methods: numerical | intergalactic medium
2011/10/12
It has been realised only recently that TeV emission from blazars can significantly heat the intergalactic medium (IGM) by pair-producing high-energy electrons and positrons, which in turn excite vigo...
Discovery of the infrared counterpart of CXOU J174437.3-323222 in the field of IGR J17448-3232: a blazar candidate viewed through the Galactic centre?
Infrared: general – Radiation mechanisms: non-thermal – X-rays: individual
2011/9/29
We present our near infrared ESO-NTT Ks band observations of the field of IGR J17448-3232 which show no extended emission consistent with the SNR but in which we identify a new counterpart, also visib...
Optical Spectral Variability of the Very-High-Energy Gamma-Ray Blazar 1ES 1011+496
Optical Spectral Variability the Very-High-Energy Gamma-Ray Blazar 1ES 1011+496
2011/1/11
We present results of five years of optical (UBVRI) observations of the very-high-energy gamma-ray blazar 1ES 1011+496 at the MDM Observatory. We calibrated UBVRI magnitudes of five comparison stars i...
Multi-wavelength Observations of the Flaring Gamma-ray Blazar 3C 66A in 2008 October
BL Lacertae objects individual (3C 66A) — galaxies ctive —gamma rays observations
2010/11/10
The BL Lacertae object 3C 66A was detected in a flaring state by the Fermi Large Area Telescope (LAT) and VERITAS in 2008 October. In addition to these gamma-ray observations, F-GAMMA, GASP-WEBT, PAIR...
Blazar jet physics in the age of Fermi
galaxies: jets gamma rays observations gamma rays theory
2010/11/9
The impact of the Fermi Gamma-ray Space Telescope on blazar research is reviewed. This
includes a brief description of the Fermi Large Area Telescope, a summary of the various classes of extragalacti...
INTEGRAL observations of the GeV blazar PKS1502+106 and of the hard X-ray bright Seyfert Galaxy Mkn841
galaxies active – quasars individual PKS 1502+106 – Galaxies Seyfert – galaxies individual Mkn 841 – radiation
2010/11/16
Context. Extragalactic nuclear activity is best explored with observations at high energies, where the most extreme flux and spectral variations are expected to occur, witnessing changes in the accret...
Optical and infrared photometry of the blazar PKS0537-441
galaxies active — galaxies BL Lacertae objects PKS0537-441
2010/11/11
We present a large collection of photometric data on the Blazar PKS 0537-441 in the VRIJHK
bands taken in 2004−2009. At least three flare-like episodes with months duration, and >3 mag
amplitu...
Physical properties of blazar jets from VLBI observations
Cosmology and Extragalactic Astrophysics (astro-ph.CO) High Energy Astrophysical Phenomena (astro-ph.HE)
2011/1/5
Relativistic jets, formed in the vicinity of central supermassive black holes in AGN, show ample evidence connecting them to physical conditions in the accretion disc and broad-line region.
Observations of the Blazar 3C 66A with the MAGIC Telescopes in Stereoscopic Mode
High Energy Astrophysical Phenomena (astro-ph.HE)
2010/12/23
We report new observations of the intermediate-frequency peaked BL Lacertae object 3C 66A with the MAGIC telescopes. The data sample we use were taken in 2009 December and 2010 January, and comprises ...