Is the Family Between the Solar Cinch Vibrant Stress while the Magnetopause Standoff Range so 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 Language Summary
New magnetopause ‘s the border amongst the near-World area, that is governed by magnetized profession manufactured in the fresh Planet’s core, and you will interplanetary space inhabited from the plasma emitted from the Sunlight called the solar power piece of cake. In this functions, i reexamine the relationship between your magnetopause position and you will parameters out of brand new solar piece of cake in the form of pc modeling. It is found the relationships ranging from solar power breeze speed and you can thickness and you may magnetopause condition is far more advanced than simply to start with envision.
1 Inclusion
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.
Has just, Nemecek et al. ( 2016 ) opposed noticed magnetopause crossings into the Shue mais aussi al. design (Shue mais aussi al., 1997 ) for http://www.datingranking.net/pl/flirt-recenzja half the very last solar power years and found medical differences involving the design and observations. They debated your ionospheric conductivity as well as the solar power piece of cake velocity are most details you to determine the magnetopause standing. Its statistical studies signifies that an average magnetopause is farther from our planet than just forecast throughout big date times which have down conductivity and highest solar power wind speed. It recommended that intensification of Ultraviolet light contributes to a growth regarding magnetospheric-ionospheric currents you to definitely reduces the magnetized pressure inside magnetosphere and the fresh new magnetopause actions earthward. Quite the opposite, enhancement of speed intensifies the new viscous correspondence within solar power piece of cake and magnetosphere enhancing the in the world magnetospheric convection and bringing a whole lot more magnetized flux on the dayside magnetosphere. We shall talk about these types of assumptions lower than regarding the paper.