Title: Magnetic reconnection and kinetic waves generated in the Earth's quasi-parallel bow shock

Abstract

Magnetic reconnection in quasi-parallel shocks, relevant to the Earth’s bow shock, is studied by means of two-dimensional full particle-in-cell simulations. As the Alfvénic Mach number increases, the propagation direction of the waves excited in the transition region changes, and the shock becomes more turbulent with more reconnection sites. In the higher Mach number shock, abundant electron-only reconnection sites are generated with scales on the order of the ion skin depth or less. Non-reconnecting current sheets can also generate electron jets and energy dissipation can occur there as well. However, non-reconnecting current sheets with the magnetic field reversal typically show a smaller energy dissipation rate than reconnecting current sheets. In the shock transition region, two types of waves are responsible for driving reconnection: one has a wavelength around three ion skin depths (d_i), and the other has a wavelength less than 1 d_i. Here, electron and ion distribution functions show that in regions where the former type of waves is excited, there are two ion beams and a single-peaked electron distribution. In contrast, in regions where the latter type of waves is excited, there are multiple electron and ion beams. The waves propagating obliquely to the magnetic field bend the magneticmore » field lines, and magnetic reconnection occurs where oppositely directed field lines come into contact.« less

Authors:

Bessho, Naoki  ^[1];

• Search DOE PAGES for author "Bessho, Naoki"
• Search DOE PAGES for ORCID "0000-0002-5431-174X"

Chen, L. -J.  ^[2];

• Search DOE PAGES for author "Chen, L. -J."
• Search DOE PAGES for ORCID "0000-0002-4768-189X"

Wang, S.  ^[1];

• Search DOE PAGES for author "Wang, S."
• Search DOE PAGES for ORCID "0000-0002-6783-7759"

Hesse, M.  ^[3];

• Search DOE PAGES for author "Hesse, M."
• Search DOE PAGES for ORCID "0000-0003-0377-9673"

Wilson, L. B.  ^[2];

• Search DOE PAGES for author "Wilson, L. B."
• Search DOE PAGES for ORCID "0000-0002-4313-1970"

Ng, J.  ^[1]

• Search DOE PAGES for author "Ng, J."
• Search DOE PAGES for ORCID "0000-0002-5183-3577"

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+ Show Author Affiliations

1. Univ. of Maryland, College Park, MD (United States); NASA Goddard Space Flight Center (GSFC), Greenbelt, MD (United States)
2. NASA Goddard Space Flight Center (GSFC), Greenbelt, MD (United States)
3. Univ. of Bergen (Norway); Southwest Research Institute, San Antonio, TX (United States)

Publication Date:

Fri Sep 18 00:00:00 EDT 2020

Research Org.:

Univ. of Maryland, College Park, MD (United States)

Sponsoring Org.:

USDOE Office of Science (SC), Fusion Energy Sciences (FES); National Science Foundation (NSF); National Aeronautics and Space Administration (NASA); Research Council of Norway

OSTI Identifier:

1770774

Alternate Identifier(s):

OSTI ID: 1664472

Grant/Contract Number:  

SC0016278; AGS-1619584; AGS-1552142; 80NSSC18K1369; 223252/F50

Resource Type:

Accepted Manuscript

Journal Name:

Physics of Plasmas

Additional Journal Information:

Journal Volume: 27; Journal Issue: 9; Journal ID: ISSN 1070-664X

Publisher:

American Institute of Physics (AIP)

Country of Publication:

United States

Language:

English

Subject:

70 PLASMA PHYSICS AND FUSION TECHNOLOGY; Magnetic reconnection; Magnetospheric dynamics; Kinetic waves; Foreshock; Wave mechanics; Particle-in-cell method; Fluid mechanics; Shock waves; Thermodynamic systems