Revisiting correlations between broad-line and jet emission variations for AGNs: 3C 120 and 3C 273
Revisiting correlations between broad-line and jet emission variations for AGNs: 3C 120 and 3C 273
复制标题
重新审视活动星系核的宽线和射流发射变化之间的相关性：3C 120 和 3C 273
DOI：
10.1093/mnras/stv601
复制
发表时间：
2014-12
影响因子：
4.8
通讯作者：
Li S. K.
中科院分区：
文献类型：
--
作者：
Liu H. T;Bai J. M.;Feng H. C.;Li S. K.
我们重新研究了宽线和喷流发射变化之间的相互关联问题，并旨在确定活动星系核喷流中射电（和伽马射线）发射区域的位置。考虑到球面宽线区域（BLR）内云的半径和数密度的径向分布，我们推导出了连接喷流发射位置R-jet与宽线和喷流发射变化之间的时差tau（ob）和BLR半径的新公式。此外，还推导出了圆盘状BLR和球壳型BLR的计算公式。采用与模型无关的通量随机化/随机子集选择方法估计tau（ob）。对于3C 120，在15ghz发射和H β， H γ和He II lambda 686线之间发现了约0.3年的正滞后，包括新发表的论文中的宽线数据，表明线变化领先于15ghz。每条宽线光曲线对应一次射电爆发。3C 120得到R-jet = 1.1 ~ 1.5 parsec （pc）。对于3C 273，在射电发射光曲线与Balmer线、Ly α λ 1216线和CIV λ 1549线的互相关函数中发现了负时间滞后的共同特征。得到3C 273的R-jet = 1.0-2.6 pc。估计的r射流与3C 120和3C 273相当，伽马射线发射位置与中央发动机的距离将在类似的1-3 pc内。对比表明，云数密度、半径径向分布和BLR结构对r -射流的影响可以忽略不计。
We restudy the issue of cross-correlations between broad-line and jet emission variations, and aim to locate the position of a radio (and gamma-ray) emitting region in a jet of active galactic nuclei. Considering the radial profiles of the radius and number density of clouds in a spherical broad-line region (BLR), we derive new formulae connecting the jet-emitting position R-jet to the time lag tau(ob) between broad-line and jet emission variations, and the BLR radius. Also, formulae are derived for a disc-like BLR and a spherical shell BLR. The model-independent flux randomization/random subset selection method is used to estimate tau(ob). For 3C 120, positive lags of about 0.3 yr are found between the 15 GHz emission and the H beta, H gamma and He II lambda 686 lines, including broad-line data in a newly published paper, indicating that the line variations lead the 15 GHz ones. Each of the broad-line light curves corresponds to a radio outburst. R-jet = 1.1-1.5 parsec (pc) is obtained for 3C 120. For 3C 273, a common feature of negative time lags is found in the cross-correlation functions between light curves of radio emission and the Balmer lines, as well as Ly alpha lambda 1216 and CIV lambda 1549 lines. R-jet = 1.0-2.6 pc is obtained for 3C 273. The estimated R-jet is comparable for 3C 120 and 3C 273, and the gamma-ray-emitting positions will be within similar to 1-3 pc from the central engines. Comparisons show that the cloud number density and radius radial distributions and the BLR structures have only negligible effects on R-jet.
登录
查看更多内容
影响因子：
4.8
作者：
G. Ghisellini;F. Tavecchio;L. Foschini;G. Bonnoli;G. Tagliaferri
通讯作者：
G. Ghisellini;F. Tavecchio;L. Foschini;G. Bonnoli;G. Tagliaferri
影响因子：
4.8
作者：
T. Alexander;H. Netzer
通讯作者：
T. Alexander;H. Netzer
影响因子：
6.5
作者：
S. Soldi;M. Turler;S. Paltani;H. Aller;M. Aller;G. Burki;M. Chernyakova;A. Lahteenmaki;I. McHardy;E. I. Robson;R. Staubert;M. Tornikoski;R. Walter;T. J. C. Isdc;G. Observatory;U. Michigan;Dias;Metsahovi Radio Observatory;U. Southampton;UK Astronomy Technology Centre;Iaa Tubingen
通讯作者：
S. Soldi;M. Turler;S. Paltani;H. Aller;M. Aller;G. Burki;M. Chernyakova;A. Lahteenmaki;I. McHardy;E. I. Robson;R. Staubert;M. Tornikoski;R. Walter;T. J. C. Isdc;G. Observatory;U. Michigan;Dias;Metsahovi Radio Observatory;U. Southampton;UK Astronomy Technology Centre;Iaa Tubingen
影响因子：
4.8
作者：
T. Alexander;H. Netzer
通讯作者：
T. Alexander;H. Netzer
影响因子：
4.8
作者：
XueGuang Zhang
通讯作者：
XueGuang Zhang