The Detection of Two New Superluminal Components in 1156+295 at 15 GHz
We present the results from 4-epoch VLBA polarimetric observations of the blazar 1156+295 from 2003 to 2005 at 15 GHz. The source is resolved into core-jet structure and five components well fit the jet emission struture (named as C2, C3, C4, C5 and C6 from the outermost inwards). C5 and C6 are newly detected compo nents from our observations. Combining with previous observations and archive data at 15GHz, we determined proper motions of jet components. Four components were detected significant proper motions, 0.55+0.05 mas yr-l (C2), 0.1710.03 mas yr-l (C4), 0.14±0.02 mas yr-l (C5) and 0.26±0.01 mas yr-l (C6); these numbers cor respond to apparent transverse velocity of 19.4+1.8c, 6.O±l.lc, 4.9± 0.7c, 9.2±0.4c respectively (qo=0.5, Ho = 65 km s-l Mpc-l). Component C3 was detected with a proper motion of 0.33±0.12 mas yr-l from 1999 to 2001, but it had no significant radial motion from 2001 to 2005. The exotic motion pattern of C3 is likely due to projection effect when it runs into a curved trajectory in 2001. From epoch 2004.25 to 2005.20, the total flux density of 1156+295 increased by a factor of 2.2, and the polarized flux density increased by a factor of 1.3. In addition, the Electric Vector Position Angle (EVPA) in the core region experienced a sudden change from ggo to 18o. The subtle changes in total and polarized emission structure in the core may be related to creation and ejection of a new jet component.
galaxies nuclei - galaxies jets -galaxies quasars individual 1156+295
Wei Zhao Xiaoyu Hong Tao An Jun Yang
Shanghai Astronomical Observatory,Chinese Academy of Sciences,Shanghai 200030,China Graduate School Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 200030, China Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 200030, China Graduate Sc
国际会议
The 10th Asian-Pacific Regional International Astronomical Union Meeting(第十届亚洲及太平洋地区天文学大会 APRIM)
昆明
英文
287-288
2008-08-03（万方平台首次上网日期，不代表论文的发表时间）