PIC simulation of a shock tube: Implications for wave transmission in the heliospheric boundary region. (arXiv:2001.02170v1 [physics.space-ph])
<a href="http://arxiv.org/find/physics/1/au:+Matsukiyo_S/0/1/0/all/0/1">S. Matsukiyo</a>, <a href="http://arxiv.org/find/physics/1/au:+Noumi_T/0/1/0/all/0/1">T. Noumi</a>, <a href="http://arxiv.org/find/physics/1/au:+Zank_G/0/1/0/all/0/1">G. P. Zank</a>, <a href="http://arxiv.org/find/physics/1/au:+Washimi_H/0/1/0/all/0/1">H. Washimi</a>, <a href="http://arxiv.org/find/physics/1/au:+Hada_T/0/1/0/all/0/1">T. Hada</a>
A shock tube problem is solved numerically by using one-dimensional full
particle-in-cell simulations under the condition that a relatively tenuous and
weakly magnetized plasma is continuously pushed by a relatively dense and
strongly magnetized plasma having supersonic relative velocity. A forward and a
reverse shock and a contact discontinuity are self-consistently reproduced. The
spatial width of the contact discontinuity increases as the angle between the
discontinuity normal and ambient magnetic field decreases. The inner structure
of the discontinuity shows different profiles between magnetic field and plasma
density, or pressure, which is caused by a non-MHD effect of the local plasma.
The region between the two shocks is turbulent. The fluctuations in the
relatively dense plasma are compressible and propagating away from the contact
discontinuity, although the fluctuations in the relatively tenuous plasma
contain both compressible and incompressible components. The source of the
compressible fluctuations in the relatively dense plasma is in the relatively
tenuous plasma. Only compressible fast mode fluctuations generated in the
relatively tenuous plasma are transmitted through the contact discontinuity and
propagate in the relatively dense plasma. These fast mode fluctuations are
steepened when passing the contact discontinuity. This wave steepening and
probably other effects may cause the broadening of the wave spectrum in the
very local interstellar medium plasma. The results are discussed in the context
of the heliospheric boundary region or heliopause.
A shock tube problem is solved numerically by using one-dimensional full
particle-in-cell simulations under the condition that a relatively tenuous and
weakly magnetized plasma is continuously pushed by a relatively dense and
strongly magnetized plasma having supersonic relative velocity. A forward and a
reverse shock and a contact discontinuity are self-consistently reproduced. The
spatial width of the contact discontinuity increases as the angle between the
discontinuity normal and ambient magnetic field decreases. The inner structure
of the discontinuity shows different profiles between magnetic field and plasma
density, or pressure, which is caused by a non-MHD effect of the local plasma.
The region between the two shocks is turbulent. The fluctuations in the
relatively dense plasma are compressible and propagating away from the contact
discontinuity, although the fluctuations in the relatively tenuous plasma
contain both compressible and incompressible components. The source of the
compressible fluctuations in the relatively dense plasma is in the relatively
tenuous plasma. Only compressible fast mode fluctuations generated in the
relatively tenuous plasma are transmitted through the contact discontinuity and
propagate in the relatively dense plasma. These fast mode fluctuations are
steepened when passing the contact discontinuity. This wave steepening and
probably other effects may cause the broadening of the wave spectrum in the
very local interstellar medium plasma. The results are discussed in the context
of the heliospheric boundary region or heliopause.
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