Manel Perucho, Valenti Bosch-Ramon
High-mass microquasars consist of a massive star and a compact object, the
latter producing jets that will interact with the stellar wind. The evolution
of the jets, and ultimately their radiative outcome, could depend strongly on
the inhomogeneity of the wind, which calls for a detailed study. The
hydrodynamics of the interaction between a jet and a clumpy wind is studied,
focusing on the global wind and single clump-jet interplay. We have performed,
using the code \textit{Ratpenat}, three-dimensional numerical simulations of a
clumpy wind interacting with a mildly relativistic jet, and of individual
clumps penetrating into a jet. For typical wind and jet velocities, filling
factors of about > 0.1 are already enough for the wind to be considered as
clumpy. An inhomogeneous wind makes the jet more unstable when crossing the
system. Kinetic luminosities of the order 1.e37 erg/s allow the jet to reach
the borders of a compact binary with an O star, as in the smooth wind case,
although with a substantially higher degree of disruption. When able to enter
into the jet, clumps are compressed and heated during a time of about their
size divided by the sound speed in the shocked clump. Then, clumps quickly
disrupt, mass-loading and slowing down the jet. We conclude that moderate wind
clumpiness makes already a strong difference with the homogeneous wind case,
enhancing jet disruption, mass-loading, bending, and likely energy dissipation
in the form of emission. All this can have observational consequences at
high-energies and also in the large scale radio jets.
View original:
http://arxiv.org/abs/1112.2520
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