A&A 429, 1069-1080 (2005)
DOI: 10.1051/0004-6361:20041348
Solar cycle influence on the interaction of the solar wind with Local Interstellar Cloud
V. Izmodenov1, 2, Y. Malama2 and M. S. Ruderman31 Lomonosov Moscow State University, Department of Aeromechanics and Gas Dynamics, Faculty of Mechanics and Mathematics, and Institute of Mechanics, Moscow 119899, Russia
e-mail: izmod@ipmnet.ru
2 Institute for Problems in Mechanics, Russian Academy of Sciences, Prospect Vernadskogo 101-1, Moscow 117526, Russia
3 Department of Applied Mathematics, University of Sheffield, Hicks Building, Hounsfield Road, Sheffield S3 7RH, UK
(Received 25 May 2004 / Accepted 3 September 2004)
Abstract
We present results of a new time-dependent kinetic model
of the H atom penetration through the solar wind - interstellar
medium interaction region. A kinetic 6D (time, two dimensions in
space, and three dimensions in velocity-space) equation for
interstellar H atoms was solved self-consistently with
time-dependent Euler equations for the solar wind and interstellar
charged components. We study the response of the interaction
region to 11-year solar cycle variations of the solar wind dynamic
pressure. It is shown that the termination shock location varies
within
7 AU, the heliopause variation is ~4 AU, and the
bow shock variation is negligible. At large heliocentric
distances, the solar cycle induces 10-12% fluctuations in the
number density of both primary and secondary interstellar H atoms
and atoms created in the inner heliosheath. We underline the
kinetic behavior of the fluctuations of the H atom populations.
Closer to the Sun the fluctuations increase up to 30-35% at 5 AU
due to solar cycle variation of the charge exchange rate. Solar
cycle variations of interstellar H atoms in the heliospheric
interface and within the heliosphere may have major importance for
the interpretation of H atom observations inside the heliosphere.
Key words: Sun: solar wind -- interplanetary medium -- ISM : atoms -- Sun: activity -- hydrodynamics
© ESO 2005