6533b857fe1ef96bd12b46ef
RESEARCH PRODUCT
VLBI detection of the HST-1 feature in the M87 jet at 2 cm
Yuri Y. KovalevYuri Y. KovalevEduardo RosEduardo RosMatthew L. ListerC. S. Changsubject
Active galactic nucleusCosmology and Nongalactic Astrophysics (astro-ph.CO)active [Galaxies]010504 meteorology & atmospheric sciencesRadio galaxyFluxFOS: Physical sciencesgalaxies [Radio continuum]Astrophysics01 natural scienceslaw.inventionlaw0103 physical sciencesVery-long-baseline interferometryUNESCO::ASTRONOMÍA Y ASTROFÍSICA::Otras especialidades astronómicasBlazar010303 astronomy & astrophysicsUNESCO::ASTRONOMÍA Y ASTROFÍSICA::Cosmología y cosmogonia::Galaxias0105 earth and related environmental sciencesPhysicsSuperluminal motionAstronomy and Astrophysics:ASTRONOMÍA Y ASTROFÍSICA::Cosmología y cosmogonia::Galaxias [UNESCO]Radio continuum : galaxies; Techniques : high angular resolution; Techniques : interferometric; Galaxies : active; Galaxies : jetshigh angular resolution [Techniques]InterferometrySpace and Planetary Scienceinterferometric [Techniques]jets [Galaxies]:ASTRONOMÍA Y ASTROFÍSICA::Otras especialidades astronómicas [UNESCO]FlareAstrophysics - Cosmology and Nongalactic Astrophysicsdescription
A bright feature 80 pc away from the core in the powerful jet of M87 shows highly unusual properties. Earlier radio, optical and X-ray observations have shown that this feature, labeled HST-1, is superluminal, and is possibly connected with the TeV flare detected by HESS in 2005. It has been claimed that this feature might have a blazar nature, due to these properties. To examine the possible blazar-like nature of HST-1, we analyzed lambda 2 cm VLBA archival data from dedicated full-track observations and the 2 cm survey/MOJAVE VLBI monitoring programs obtained between 2000 and 2009. Applying VLBI wide-field imaging techniques, the HST-1 region was imaged at milliarcsecond resolution. Here we present the first 2 cm VLBI detection of this feature in observations from early 2003 to early 2007, and analyze its evolution over this time. Using the detections of HST-1, we find that the projected apparent speed is 0.61 +/- 0.31 c. A comparison of the VLA and VLBA flux densities of this feature indicate that is mostly resolved on molliarcsecond scales. This feature is optically thin between lambda 2 cm and lambda 20 cm. We do not find evidence of a blazar nature for HST-1.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2010-01-01 |