TY - JOUR

T1 - Relativistic unsteady Petschek-type model of magnetic reconnection

AU - Tolstykh, Yu V.

AU - Semenov, V. S.

AU - Biernat, H. K.

AU - Heyn, M.F.

AU - Penz, T.

PY - 2007/1/1

Y1 - 2007/1/1

N2 - A model of time-dependent Petschek-type reconnection of arbitrary strong magnetic fields is presented where all necessary relativistic effects are taken into account. Reconnection is supposed to be initiated due to a local decrease of the plasma conductivity inside the diffusion region, which results in the appearance of an electric field along the X-line. This electric field is considered as a given arbitrary function of time. Then all MHD parameters as well as the shape of the moving Petschek-type shocks are obtained from the ideal relativistic MHD equations written in terms of 4-magnetic field and 4-velocity vectors as suggested by Lichnerowicz. The analysis is restricted to a symmetric current sheet geometry and to the case of weak reconnection, where the reconnection rate is supposed to be a small parameter. The solution obtained extends the well-known Petschek model for the steady-state case to incorporate relativistic effects of impulsive reconnection. It is shown that the plasma is accelerated at the slow shocks to ultrarelativistic velocities with high Lorentz-factors only for current layers embedded into strong magnetic fields and low-beta plasmas. In this case the plasma is strongly compressed and heated while the normal size of the outflow region with the accelerated plasma becomes very small.

AB - A model of time-dependent Petschek-type reconnection of arbitrary strong magnetic fields is presented where all necessary relativistic effects are taken into account. Reconnection is supposed to be initiated due to a local decrease of the plasma conductivity inside the diffusion region, which results in the appearance of an electric field along the X-line. This electric field is considered as a given arbitrary function of time. Then all MHD parameters as well as the shape of the moving Petschek-type shocks are obtained from the ideal relativistic MHD equations written in terms of 4-magnetic field and 4-velocity vectors as suggested by Lichnerowicz. The analysis is restricted to a symmetric current sheet geometry and to the case of weak reconnection, where the reconnection rate is supposed to be a small parameter. The solution obtained extends the well-known Petschek model for the steady-state case to incorporate relativistic effects of impulsive reconnection. It is shown that the plasma is accelerated at the slow shocks to ultrarelativistic velocities with high Lorentz-factors only for current layers embedded into strong magnetic fields and low-beta plasmas. In this case the plasma is strongly compressed and heated while the normal size of the outflow region with the accelerated plasma becomes very small.

KW - Magnetic reconnection

KW - Relativistic MHD

KW - Slow shock

UR - http://www.scopus.com/inward/record.url?scp=35248824627&partnerID=8YFLogxK

U2 - 10.1016/j.asr.2007.01.013

DO - 10.1016/j.asr.2007.01.013

M3 - Article

AN - SCOPUS:35248824627

VL - 40

SP - 1538

EP - 1542

JO - Advances in Space Research

JF - Advances in Space Research

SN - 0273-1177

IS - 10

ER -