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arXiv · 1310.6312

A sensitive study of the peculiar jet structure HST-1 in M87

Carolina Casadio·José L. Gómez·Marcello Giroletti·Gabriele Giovannini·Kazuhiro Hada·Christian Fromm·Manel Perucho·José-María Martí
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Abstract

To obtain a better understanding of the location and mechanisms for the production of the gamma-ray emission in jets of AGN we present a detailed study of the HST-1 structure, 0.8 arcsec downstream the jet of M87, previously identified as a possible candidate for TeV emission. HST-1 shows a very peculiar structure with superluminal as well as possible stationary sub-components, and appears to be located in the transition from a parabolic to a conical jet shape, presumably leading to the formation of a recollimation shock. This scenario is supported by our new RHD simulations in which the interaction of a moving component with a recollimation shock leads to the appearance of a new superluminal component. To discern whether HST-1 is produced by a recollimation shock or some other MHD instability, we present new polarimetric 2.2 and 5 GHz VLBA, as well as 15, 22 and 43 GHz JVLA observations obtained between November 2012 and March 2013.

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Carolina Casadio, José L. Gómez, Marcello Giroletti, Gabriele Giovannini, Kazuhiro Hada, Christian Fromm, Manel Perucho, José-María Martí. 2013-10-23. A sensitive study of the peculiar jet structure HST-1 in M87. https://doi.org/10.1051/epjconf%2F20136106004

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