Simulation of the Scattering of Continuously Injected Pickup Ions outside the Heliopause

Sheng, Ding1; Liu, Kaijun2; Florinski, V3,4; Perez, J. D.1

2021-12-01

10.3847/1538-4357/ac2a2e

ASTROPHYSICAL JOURNAL   影响因子和分区

0004-637X

1538-4357

Hybrid simulations in 2D space and 3D velocity dimensions with continuous injection of pickup ions (PUIs) provide insight into the plasma processes that are responsible for the pitch angle scattering of PUIs outside the heliopause. The present investigation includes for the first time continuous injection of PUIs and shows how the scattering depends on the energy of the PUIs and the strength of the background magnetic field as well as the dependence on the injection rate of the time for the isotropization of the pitch angle distribution. The results demonstrate that, with the gradual injection of PUIs of a narrow ring velocity distribution perpendicular to the background magnetic field, oblique mirror mode waves develop first, followed by the growth of quasiparallel propagating ion cyclotron waves. Subsequently, the PUIs are scattered by the excited waves and gradually approach an isotropic distribution. A time for isotropization is defined to be the time at which T ( divide divide )/T (perpendicular to), i.e., the ratio of the parallel to perpendicular PUI thermal energy changes from approximate to 0 to approximate to 0.15. By varying the PUI injection rate, estimates of the time for the PUI distribution to be isotropized are presented. The isotropization time obtained is shorter, approximate to months, than the time, approximate to years, required by the conventional secondary ENA mechanism to explain the IBEX ENA ribbon.

SCI

英语

其他

NASA[80NSSC18K1209]

Astronomy & Astrophysics

Astronomy & Astrophysics

WOS:000727006900001

IOP Publishing Ltd

SPACE SCIENCE

Web of Science

1.Auburn Univ, Dept Phys, Auburn, AL 36849 USA
2.Southern Univ Sci & Technol, Dept Earth & Space Sci, Shenzhen 518055, Peoples R China
3.Univ Alabama, Dept Space Sci, Huntsville, AL 35899 USA
4.Univ Alabama, Ctr Space Plasma & Aeron Res, Huntsville, AL 35899 USA

Sheng, Ding,Liu, Kaijun,Florinski, V,et al. Simulation of the Scattering of Continuously Injected Pickup Ions outside the Heliopause[J]. ASTROPHYSICAL JOURNAL,2021,922(2).

Sheng, Ding,Liu, Kaijun,Florinski, V,&Perez, J. D..(2021).Simulation of the Scattering of Continuously Injected Pickup Ions outside the Heliopause.ASTROPHYSICAL JOURNAL,922(2).

Sheng, Ding,et al."Simulation of the Scattering of Continuously Injected Pickup Ions outside the Heliopause".ASTROPHYSICAL JOURNAL 922.2(2021).