step 3 Discussion and Results

Really empirical magnetopause habits suppose a general family involving the solar cinch vibrant stress as well as the magnetopause standoff distance step 1, in which N remains lingering for everybody solar power wind conditions. In the artificial operates, i changes singular solar wind plasma factor, often this new density or acceleration, acquiring the same action-for example grows throughout the active tension in both cases. We make simulations getting northward and southward IMF and you can estimate the benefit legislation list Letter. I compare several versions of your own SWMF and you may LFM-Combine patterns and obtain equivalent trend for everybody patterns just like the said lower than.

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 B_z 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 B_z 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 V_SW. 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 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 R_Sub by the Shue et al. ( 1997 ) model and obtained that the model underestimates R_Sub 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 our performs, i only use MHD simulations making works towards the artificial solar power breeze conditions. Although not, we feel one to MHD patterns replicate reasonably really the newest magnetopause standoff point getting regular solar piece of cake conditions (Samso ). I greet that this functions will assist in the growth of coming empirical magnetopause habits. One of the forthcoming objectives that'll research distinctions of the dayside magnetopause is the Solar power Snap Magnetosphere Ionosphere Link Explorer (SMILE) (Raab et al., 2016 ). Having fun with Smile, we are capable receive a continuing date series of the latest magnetopause standoff range to have changeable solar power breeze criteria and have now confirm prospective empirical activities.

Acknowledgments

Which functions was achieved with the SWMF/BATSRUS gadgets put up on College or university from Michigan Heart to own Place Ecosystem Acting therefore the LFM-Combine design readily available from the NASA Area Matched Acting Heart ( In particular, we used consequence of the new works Andrey_Samsonov_072419_(1-4). Good. A. S. and you can Grams. B. Roentgen. recognize assistance on Uk Room Agency around Offer ST/R002258/1. Y. V. B. is actually backed by the newest STFC RAL Room IHR offer.