摘要
We present the X-ray variability properties of the X-ray and TeV bright blazar Mrk 421 with a-60 ks long XMM-Newton observation performed on November 9-10,2005.The source experienced a pronounced flare,of which the inter-band time lags were determined with a very high confidence level.The soft(0.6-0.8 keV) X-ray variations lagged the hard(4-10 keV) ones by 1.09+0.11-0.12 ks,and the soft lag increases with increasing difference in the photon energy.The energy-dependent soft lags can be well fitted with the difference of the energy-dependent cooling timescales of the relativistic electron distribution responsible for the observed X-ray emission,which constrains the magnetic field strength and Doppler factor of the emitting region to be Bδ 1/3-1.78 Gauss.
We present the X-ray variability properties of the X-ray and TeV bright blazar Mrk 421 with a-60 ks long XMM-Newton observation performed on November 9-10,2005.The source experienced a pronounced flare,of which the inter-band time lags were determined with a very high confidence level.The soft(0.6-0.8 keV) X-ray variations lagged the hard(4-10 keV) ones by 1.09+0.11-0.12 ks,and the soft lag increases with increasing difference in the photon energy.The energy-dependent soft lags can be well fitted with the difference of the energy-dependent cooling timescales of the relativistic electron distribution responsible for the observed X-ray emission,which constrains the magnetic field strength and Doppler factor of the emitting region to be Bδ 1/3-1.78 Gauss.
作者
ZHANG YouHong1,HOU ZhengTian2,SHAO Li3 & ZHANG Peng1 1 Department of Physics and Tsinghua Center for Astrophysics(THCA),Tsinghua University,Beijing 100084,China
2 Group of Mathematics and Physics,Shangqiu Medical College,Shangqiu 476100,China
3 Max-Planck-Institut für extraterrestrische Physik,Postfach 1312,Garching 85741,Germany
基金
supported by the National Basic Research Program of China (Grant No. 2009CB824800)
the National Natural Science Foundation of China (Grant Nos. 10878011, 10733010 and 10473006)
the Key Project of the Chinese Ministry of Education (Grant No. 106009)
Tsinghua University Project for Top Scholars
