3 Conversation and you will Conclusions
Really empirical magnetopause patterns imagine a broad relatives amongst the solar cinch dynamic pressure and the magnetopause standoff range step one, in which Letter remains constant for everybody solar cinch criteria. About phony works, i transform just one solar power cinch plasma factor, either the density otherwise velocity, obtaining the exact same step-such as for instance increases on the vibrant pressure in both cases. I make simulations to have northward and you can southward IMF and assess the advantage rules directory N. We evaluate numerous items of one’s SWMF and you will LFM-Merge patterns and get comparable trend for everyone habits given that informed me below.
Our results also show that the increase in the ionospheric conductivity or the use of a model with the additional inner magnetosphere-ionosphere block result in decrease in N. Therefore, we cannot derive a single N from the MHD simulations because the dispersion in N between the models is large; however, all models predict the same changes between different runs related to the density and velocity increases, and Bz sign.
The simulations we present suggest that dayside magnetopause reconnection influences the magnetic field magnitude at geosynchronous orbit near subsolar point. We obtain different geosynchronous magnetic fields in northward and southward IMF runs with the same dynamic pressure. Moreover, the magnetic field magnitude is also different when comparing the runs in which both the dynamic pressure and Bz are kept the same and only the ratio between the solar wind ? and V is different. Increasing velocity instead of density for a southward IMF, we increase the magnetopause reconnection rate and this results in an observable difference in the magnetic field at geosynchronous orbit with a smaller |B| corresponding to a larger VSW. Similar variations at geosynchronous orbit are observed in northward/southward turning events with a constant solar wind dynamic pressure (Samso ).
Our results partly agree with the results in Nemecek et al. ( 2016 ). We find that an increase in the ionospheric conductivity causes stronger variations of the magnetopause standoff distance, but, contrary to Nemecek et al. ( 2016 ), an increase in the solar wskazówki dotyczące loveroulette wind velocity may also enhance variations of the standoff distance. However, we cannot compare our results with Nemecek et al. ( 2016 ) directly. Nemecek et al. ( 2016 ) normalized observed RSandwich by the Shue et al. ( 1997 ) model and obtained that the model underestimates RSandwich for high velocities. First, we note that it would agree with a numerical model for which N>6.6 since N=6.6 in Shue et al. ( 1997 ). Second, variations of the solar wind velocity cannot be treated independently in the observations, they correlate with variations of the magnetic field (Owens & Cargill, 2002 ), and even (on a large time scale) with the ionospheric conductivity because higher velocities are usually observed at solar maximum. Therefore, it is difficult to make a straightforward conclusion from these results.
Within really works, i use only MHD simulations making runs toward artificial solar power cinch criteria. Yet not, we believe one MHD patterns replicate reasonably better the latest magnetopause standoff distance to have regular solar breeze conditions (Samso ). We enjoy that this really works will help in the growth of future empirical magnetopause designs. Among forthcoming objectives that can research variations of your dayside magnetopause is the Solar power Wind Magnetosphere Ionosphere Hook Explorer (SMILE) (Raab mais aussi al., 2016 ). Using Look, we will be in a position to obtain a continuing date series of the newest magnetopause standoff distance to own variable solar piece of cake criteria and then have examine potential empirical patterns.
Acknowledgments
This really works was carried out by using the SWMF/BATSRUS systems create from the University out-of Michigan Cardiovascular system to own Area Ecosystem Modeling while the LFM-Mix model available through the NASA Neighborhood Matched Acting Heart ( Specifically, i put result of the fresh new operates Andrey_Samsonov_072419_(1-4). An excellent. Good. S. and you may Grams. B. R. know support from the United kingdom Area Department less than Grant ST/R002258/step 1. Y. V. B. are supported by the new STFC RAL Room IHR grant.