TY - GEN
T1 - Particle acceleration at shocks
T2 - 7th Annual International Astrophysics Conference on Particle Acceleration and Transport in the Heliosphere and Beyond
AU - Jokipii, J. R.
AU - Kóta, J.
PY - 2008
Y1 - 2008
N2 - We consider the acceleration of charged particles and anomalous cosmic rays (ACR) at propagating shocks and especially at the heliospheric termination shock, when upstream variations cause spatial variations along the shock face, or, alternatively, if the global spatial geometry causes the shock to vary. Here we present the results a new analytic solution for the case of a shock in which the injection low-energy particles varies with position along the shock face. We find that, downstream of the shock, positive spatial gradients together with modulation-like and multiple-power-law spectral features are naturally produced by plausible spatial variations at the shock. Similar effects also result from large-scale or global spatial structure. These various effects show promising qualitative agreement with observations at and near the heliospheric termination shock, suggesting that they may play an important role.
AB - We consider the acceleration of charged particles and anomalous cosmic rays (ACR) at propagating shocks and especially at the heliospheric termination shock, when upstream variations cause spatial variations along the shock face, or, alternatively, if the global spatial geometry causes the shock to vary. Here we present the results a new analytic solution for the case of a shock in which the injection low-energy particles varies with position along the shock face. We find that, downstream of the shock, positive spatial gradients together with modulation-like and multiple-power-law spectral features are naturally produced by plausible spatial variations at the shock. Similar effects also result from large-scale or global spatial structure. These various effects show promising qualitative agreement with observations at and near the heliospheric termination shock, suggesting that they may play an important role.
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U2 - 10.1063/1.2982476
DO - 10.1063/1.2982476
M3 - Conference contribution
AN - SCOPUS:52349089270
SN - 9780735405660
T3 - AIP Conference Proceedings
SP - 390
EP - 396
BT - Particle Acceleration and Transport in the Heliosphere and Beyond - 7th Annual International Astrophysics Conference
Y2 - 7 March 2008 through 13 March 2008
ER -