# Collisionless Reconnection In Magnetohydrodynamic and Kinetic Turbulence

## Abstract

It has recently been proposed (Loureiro & Boldyrev 2017; Mallet et al. 2017) that the inertial interval in magnetohydrodynamic (MHD) turbulence is terminated at small scales not by a Kolmogorov-like dissipation region, but rather by a new sub-inertial interval mediated by tearing instability. However, many astrophysical plasmas are nearly collisionless so that the MHD approximation is not applicable to turbulence at small scales. In this paper, we propose the extension of the theory of reconnection-mediated turbulence to plasmas which are so weakly collisional that the reconnection occurring in the turbulent eddies is caused by electron inertia rather than by resistivity. We find that the transition scale to reconnection-mediated turbulence depends on the plasma beta and on the assumptions of the plasma turbulence model. However, in all cases analyzed, the energy spectra in the reconnection-mediated interval range from $$E(\k_\perp) dk_\perp \propto k_\perp^{-8/3} dk_\perp$$ to $$E(k_\perp) dk_\perp \propto k_\perp^{-3} dk_\perp$$.

- Authors:

- Publication Date:

- DOE Contract Number:
- SC0016214

- Research Org.:
- Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Plasma Science and Fusion Center

- Sponsoring Org.:
- USDOE Office of Science (SC), Basic Energy Sciences (BES)

- Subject:
- 70 PLASMA PHYSICS AND FUSION TECHNOLOGY

- OSTI Identifier:
- 1880244

- DOI:
- https://doi.org/10.7910/DVN/JTKKXJ

### Citation Formats

```
Loureiro, Nuno F., and Boldyrev, Stanislav.
```*Collisionless Reconnection In Magnetohydrodynamic and Kinetic Turbulence*. United States: N. p., 2018.
Web. doi:10.7910/DVN/JTKKXJ.

```
Loureiro, Nuno F., & Boldyrev, Stanislav.
```*Collisionless Reconnection In Magnetohydrodynamic and Kinetic Turbulence*. United States. doi:https://doi.org/10.7910/DVN/JTKKXJ

```
Loureiro, Nuno F., and Boldyrev, Stanislav. 2018.
"Collisionless Reconnection In Magnetohydrodynamic and Kinetic Turbulence". United States. doi:https://doi.org/10.7910/DVN/JTKKXJ. https://www.osti.gov/servlets/purl/1880244. Pub date:Thu Oct 25 00:00:00 EDT 2018
```

```
@article{osti_1880244,
```

title = {Collisionless Reconnection In Magnetohydrodynamic and Kinetic Turbulence},

author = {Loureiro, Nuno F. and Boldyrev, Stanislav},

abstractNote = {It has recently been proposed (Loureiro & Boldyrev 2017; Mallet et al. 2017) that the inertial interval in magnetohydrodynamic (MHD) turbulence is terminated at small scales not by a Kolmogorov-like dissipation region, but rather by a new sub-inertial interval mediated by tearing instability. However, many astrophysical plasmas are nearly collisionless so that the MHD approximation is not applicable to turbulence at small scales. In this paper, we propose the extension of the theory of reconnection-mediated turbulence to plasmas which are so weakly collisional that the reconnection occurring in the turbulent eddies is caused by electron inertia rather than by resistivity. We find that the transition scale to reconnection-mediated turbulence depends on the plasma beta and on the assumptions of the plasma turbulence model. However, in all cases analyzed, the energy spectra in the reconnection-mediated interval range from $E(\k_\perp) dk_\perp \propto k_\perp^{-8/3} dk_\perp$ to $E(k_\perp) dk_\perp \propto k_\perp^{-3} dk_\perp$.},

doi = {10.7910/DVN/JTKKXJ},

journal = {},

number = ,

volume = ,

place = {United States},

year = {2018},

month = {10}

}

Works referencing / citing this record:

##
Collisionless Reconnection in Magnetohydrodynamic and Kinetic Turbulence

journal, December 2017

- Loureiro, Nuno F.; Boldyrev, Stanislav
- The Astrophysical Journal, Vol. 850, Issue 2