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The Influence of Pickup Protons, from Interstellar Neutral Hydrogen, on the Propagation of Interplanetary Shocks from the Halloween 2003 Solar Events to ACE and Ulysses: A 3-D MHD Modeling StudyWe describe our 3-D, time ]dependent, MHD solar wind model that we recently modified to include the physics of pickup protons from interstellar neutral hydrogen. The model has a time-dependent lower boundary condition, at 0.1 AU, that is driven by source surface map files through an empirical interface module. We describe the empirical interface and its parameter tuning to maximize model agreement with background (quiet) solar wind observations at ACE. We then give results of a simulation study of the famous Halloween 2003 series of solar events. We began with shock inputs from the Fearless Forecast real ]time shock arrival prediction study, and then we iteratively adjusted input shock speeds to obtain agreement between observed and simulated shock arrival times at ACE. We then extended the model grid to 5.5 AU and compared those simulation results with Ulysses observations at 5.2 AU. Next we undertook the more difficult tuning of shock speeds and locations to get matching shock arrival times at both ACE and Ulysses. Then we ran this last case again with neutral hydrogen density set to zero, to identify the effect of pickup ions. We show that the speed of interplanetary shocks propagating from the Sun to Ulysses is reduced by the effects of pickup protons. We plan to make further improvements to the model as we continue our benchmarking process to 10 AU, comparing our results with Cassini observations, and eventually on to 100 AU, comparing our results with Voyager 1 and 2 observations.
Document ID
20130008807
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Detman, T. R. (Carmel Research Center Santa Monica, CA, United States)
Intriligator, D. S. (Carmel Research Center Santa Monica, CA, United States)
Dryer, M. (Carmel Research Center Santa Monica, CA, United States)
Sun, W. (Carmel Research Center Santa Monica, CA, United States)
Deehr, C. S. (Carmel Research Center Santa Monica, CA, United States)
Intriligator, J. (Carmel Research Center Santa Monica, CA, United States)
Date Acquired
August 27, 2013
Publication Date
March 23, 2012
Publication Information
Publication: Journal of Geophysical Research
Volume: 116
Subject Category
Solar Physics
Funding Number(s)
CONTRACT_GRANT: NNX08AE40G
Distribution Limits
Public
Copyright
Other