Intrinsic structure and kinematics of the sub-parsec scale jet of M87

Y. Y. KovalevMPIfR-Bonn; ASC Lebedev

AlaskaMay 22, 2007

• Y. Y. Kovalev (MPIfR-Bonn, ASC Lebedev)

• K. I. Kellermann (NRAO)

• M. L. Lister (Purdue University)

• D. C. Homan (Denison University)

• A. P. Lobanov(MPIfR-Bonn)

• 2 cm VLBA / MOJAVE group

Arecibo Observatory Library Colloquium

Collaborators

AlaskaMay 22, 2007

Sub-parsec-scale jet in M87 at 15 GHz

AlaskaMay 22, 2007

3 mas long “Counter-jet”

AlaskaMay 22, 2007

15 GHz

Ly et al. (2007)

Counter-jet tests: is it real or an imaging artifact?

AlaskaMay 22, 2007

Deep VLBA+VLA M87 image

A model without a counter-jet was used to producethe fake uv dataset 1: no counter-jet is detected in the image

A model with a counter-jet was used to producethe fake uv dataset 2: the counter-jet detected in the image

M87 CP results: -0.5%

AlaskaMay 22, 2007

Homan & Lister (2006)

Negative speed of a counter-jet feature

AlaskaMay 22, 2007

Intrinsic jet structure

AlaskaMay 22, 2007

Intrinsic structure of the counter jet

AlaskaMay 22, 2007

15 GHz VLBA M87 movie

AlaskaMay 22, 2007

Kinematics

AlaskaMay 22, 2007

Fastest jet speed: 0.03c

Counter-jet:-0.01c

Discussion

AlaskaMay 22, 2007

Large scale jet opening angle: 6 degrees.

Linear polarization data corrected for FRM from Zavala & Taylor (2002) suggest highly ordered longitudinal magnetic field.

We argue that the “counter-jet” is the counter-jet.Jet / Counter-jet brightness ratio is measured to be 14.Assuming viewing angle 20-40 degrees, this brightness ratio suggests that the bulk flow is (0.5-0.6)c.

If the edge brightened jet structure is due to a velocity gradient and the jet is described by a two component model with a fast spine and a slow sheath, this could explain the detected variable TeV emission from M87 (Aharonian et al. 2006) following the spine-sheath model of Ghisellini et al. (2005).

Arecibo Observatory Library ColloquiumApril 11, 2005 NASA GSFCJune 10, 2005

Thank you