Proper Motions of Jets on the Kiloparsec Scale: New Results with HST

Galaxies

卷:5

Markos Georganopoulos¹  Eileen T. Meyer¹  Eric Perlman²  Marco Chiaberge³  Jay Anderson³  Sangmo T. Sohn³  William B. Sparks³  John Biretta³  Roeland van der Marel³  Colin Norman³ 

[1] Department of Physics, University of Maryland, Baltimore County, Baltimore, MD 20742, USA;

[2] Florida Institute of Technology, Melbourne, FL 32901, USA;

[3] Space Telescope Science Institute, Baltimore, MD 21218, USA;

关键词: proper motions;    extragalactic jets;    Hubble Space Telescope;   

DOI  :  10.3390/galaxies5010008

来源: DOAJ

【 摘 要 】

The Hubble Space Telescope recently celebrated 25 years of operation. Some of the first images of extragalactic optical jets were taken by HST in the mid-1990s; with time baselines on the order of 20 years and state-of-the-art astrometry techniques, we are now able to reach accuracies in proper-motion measurements on the order of a tenth of a milliarcsecond per year. We present the results of a recent HST program to measure the kiloparsec-scale proper motions of eleven nearby optical jets with Hubble, the first sample of its kind. When paired with VLBI proper-motion measurements on the parsec scale, we are now able to map the full velocity profile of these jets from near the black hole to the final deceleration as they extend out into and beyond the host galaxy. We see convincing evidence that weak-flavor jets (i.e., FR Is) have a slowly increasing jet speed up to 100 pc from the core, where superluminal components are first seen.

【 授权许可】

Unknown