γ噪Blazar天体短时标光变的寄主星系影响(英文)

The Effect of the Host Galaxy on the Short Timescale Variability of γ-ray Loud Blazars

利用云南天文台 1m光学望远镜 2 0 0 0～ 2 0 0 1年对 3个GeV和 /或TeVγ噪Blazar天体的观测 ,发现γ噪类星体PKS 1 51 0 -0 89在R波段有一个光变时标为 4 1min的星等变化为 2 .0mag的剧烈光变 ,这是迄今为止我们所观测到的变幅最大的一个γ噪Blazar天体短时标光变。对此光变 ,可估计限制光变辐射模型的一些参数 ,如辐射区半径R、多普勒因子δ以及吸积转化效率 η等。η =59.6的值强烈预示着相对论聚束效应可较好解释γ噪Blazar天体的辐射机制。我们仔细考察了大气视宁度对光变的影响。发现对 1ES 2 3 44 + 51 4,观测到的光变与当地大气视宁度有一个弱相关 ,结果表明 ,对光变参数较小 (C <5)的光变 ,大气视宁度引起的假光变的贡献较大 。

We present the optical (V and R) photometry for three GeV and/or TeV γ-ray blazars,which were observed from 2000 through 2001,with the 1-m telescope at Yunnan Observatory.Through the observational period,the GeV γ-ray-loud source,PKS 1510-089,was very active and,it showed a significant variability of 2.0 mag within 41 min in the R band.This is the most violently rapid variability in our optical monitoring program for blazars since 1982. For this source,some physical parameters,namely the emission size,Doppler factor δ,the efficiency (η) for conversion of accreted matter into energy and luminosity are calculated. A η=59.6 was obtained,strongly implying that the relativistic beaming is responsible for the rapid variability of the γ-ray loud source.The influence of variable seeing conditions on the observations was carefully investigated.There is weak correlation between the observed variability and the local seeing conditions for the object 1ES 2344+514.The results show that the seeing fluctuations would influence the spurious variation in microvariability when the variability parameter C<5.