[Other -- Oral ]

Modeling the X-ray emission from jets observed with Chandra

Rosaria Bonito, DSFA-UNIPA-INAF-Osservatorio Astronomico di Palermo
R. Bonito (DSFA-UNIPA-INAF-OAPA), S. Orlando (INAF-OAPA), G. Peres ( DSFA-UNIPA-INAF-OAPA), F. Favata(European Space Agency, 8-10 rue Mario Nikis, 75015 Paris, France), M. Miceli (DSFA-UNIPA-INAF-OAPA), J. Eisloffel ( Thüringer Landessternwarte, Tautenburg)

In the last decade, X-rays from jets have been discovered thanks to the unprecedented resolving power of Chandra. The first convincing evidence of X-ray jets came from HH2 (2000), HH154 following shortly thereafter. Whilemore sources were detected later, HH154 remains a unique source being the nearest and the most luminous among the nearest jets: the details of the relevant X-ray morphology can be studied to a level impossible with more distant objects.Our group has investigated the mechanisms of X-ray emission from jets both analyzing multi-epochs Chandra data of HH154 and developing numerical models of jets where X-rays are generated by jets shocking onto the circumstellar medium. The analysis of Chandra data of HH 154 in different epochs allowed us to study for the first time the morphology and the evolution of the X-ray source on a time scale of 4years. We found that the source consists of an unresolved, point-like component with no detectable proper motion and an elongated component with a proper motion consistent with a shock moving away from the parent star.We present here the comparison between the Chandra observations of HH jets and our hydrodynamic model of a randomly ejected pulsed jet which reproduces the knotty morphology observed.