‘s the Relatives Amongst the Solar Cinch Vibrant Pressure in addition to Magnetopause Standoff Length thus Quick?

‘s the Relatives Amongst the Solar Cinch Vibrant Pressure in addition to Magnetopause Standoff Length thus Quick?

We present results of global magnetohydrodynamic simulations which reconsider the relationship between the solar wind dynamic pressure (Pd) and magnetopause standoff distance (RSandwich). We simulate the magnetospheric response to increases in the dynamic pressure by varying separately the solar wind density or velocity for northward and southward interplanetary magnetic field (IMF). We obtain different values of the power law indices N in the relation depending on which parameter, density, or velocity, has been varied and for which IMF orientation. The changes in the standoff distance are smaller (higher N) for a density increase for southward IMF and greater (smaller N) for a velocity increase.

Plain Code Summation

The newest magnetopause is the edge amongst the near-Earth place, that is governed by the magnetized career manufactured in the brand new Earth’s center, and interplanetary room populated from the plasma released regarding the Sunlight called the solar piece of cake. Within really works, we reexamine the partnership between your magnetopause position and details away from this new solar breeze in the shape of computer modeling. It is found your matchmaking anywhere between solar piece of cake speed and you can occurrence and magnetopause status is more state-of-the-art than in the first place think.

step 1 Introduction

The magnetopause is one of principal magnetospheric boundaries which separates dense solar wind plasma in the magnetosheath and tenuous and hot magnetospheric plasma. In response to strong solar wind pressure pulses, the magnetopause comes closer to the Earth and geosynchronous spacecraft may exit the magnetosphere and cross the magnetosheath in the subsolar region or even enter into the supersonic solar wind. To date, more than 15 empirical models of the magnetopause have been developed based on a great number of magnetopause crossings under different solar wind conditions (a list of 14 models published by Suvorova & Dmitriev, 2015 ). Chapman and Ferraro ( 1931 ) suggested that the magnetopause location can be determined from the pressure balance condition between the solar wind dynamic pressure (Pd) and the magnetic pressure of the Earth’s dipole. Besides the dynamic pressure, the second important solar wind parameter influencing the magnetopause position is the interplanetary magnetic field (IMF) Bz component (Aubry et al., 1970 ; Fairfield, 1971 ). A strong southward IMF (Bz<0) results in magnetic reconnection at the dayside magnetopause and intensification of the large-scale field-aligned (Region 1) currents connecting the magnetosphere and ionosphere and moving the magnetopause closer to the Earth (Hill & Rassbach, 1975 ; Sibeck, 1994 ). The Pd and Bz are the only two input parameters in several popular magnetopause models (e.g., Petrinec & Russell, 1996 ; Roelof & Sibeck, 1993 ; Shue et al., 1997 ; 1998 ; Sibeck et al., 1991 ). The recent (Lin et al., 2010 ) empirical model replaces the solar wind dynamic pressure by the sum of dynamic and magnetic pressures and takes into account the Earth’s dipole tilt. Moreover, several papers (Dusik et al., 2010 ; Grygorov et al., 2017 ; Merka et al., 2003 ; Samso ) note that the magnetopause significantly expands during radial IMF intervals concluding that the IMF cone angle (the angle between IMF and the Sun-Earth line) eter for calculation of the magnetopause location.

Recently, Nemecek ainsi que al. ( 2016 ) opposed noticed magnetopause crossings towards the Shue mais aussi al. design (Shue ainsi que al., 1997 ) having half of the last solar power duration and discovered medical distinctions within design and you may observations. It debated the ionospheric conductivity as well as the solar power cinch acceleration try additional variables one to determine the magnetopause standing. Their mathematical study means that the average magnetopause try further away from the planet than simply forecast throughout the go out periods that have straight down conductivity and large solar breeze speed. They suggested https://www.datingranking.net/pl/localmilfselfies-recenzja that intensification away from Ultraviolet rays leads to a growth on the magnetospheric-ionospheric currents one decreases the magnetized stress during the magnetosphere and the fresh magnetopause movements earthward. To the contrary, improvement of your own acceleration intensifies new viscous telecommunications between your solar power wind and magnetosphere enhancing the all over the world magnetospheric convection and you may providing so much more magnetized flux to your dayside magnetosphere. We’re going to explore these types of assumptions less than in the report.