Today’s Talk• Report on “Priest 60 Years Old Conference”

• Report on “Magnetic Reconnection 2003”

• Turbulent reconnection (Tanuma et al.; Vishiniac & Lazarian; Cho et al….)

• Particle acceleration in turbulence (Dmitruk et al. 2003, ApJ, 597, L81)

• Particle simulations (Tanuma et al.)

Priest 60 Years Old Conference• http://www-solar.mcs.st-and.ac.uk/~mhd03/

• Magnetic Reconnection and the Dynamic Sun

• 8-10 September 2003

• Institute of Mathematics, University of St. Andrews, Scotland.

• Linton’ talk

Programme• Reconnection Theory and Applications (Forbes,

Drake, Fujimoto, Linton, Birn, etc.)• The Dynamic Sun (Proctor, Weiss, Asai,

Klimchuk, Longcope, Galsgaard, Neukirch, Kusano, etc.)

• The Dynamic Sun and Astrophysics (Dahlburg, Antiochos, Roussev, Heyvaerts, Casse, Baty, etc.)

• Poster (Chen,Yokoyama, Miyagoshi, Suzuki, Tanuma etc.)

• Annual PLATON Network Meeting follows the meeting.

MR2003• http://www.aph.caltech.edu/mr2003/

• Fifth US-Japan Workshop on Magnetic Reconnection, Plasma Merging, and Magnetic Jets

• November 3-5, 2003

• Catalina Canyon Resort, Catalina Island, California

• Ono-san’s talk

• Tanuma’s talk

Program• Particle heating during reconnection (Lin, Hoshino,

Oieroset, Birn, Ono)• Jets, dynamo, & reconnection (Hirose, Kudoh, Bellan, Li)• Turbulent versus Laminar reconnection (Wygant, Ji,

Diamond, Bale, Horiuchi, Lazarian)• Macroscale structure (Kawamori, Tanuma)• Structure and scaling of reconnection (Egedal, Terry, Shay,

Cowley, Fujimoto, Kusano)• Guide versus null field reconnection (Prager, Porcelli,

Cothran, Fuselier, Hesse, Swisdak)• Poster (Colgate, Furno, Uzdensky, T.Nakamura, Phan,

M.Nakamura, Tanaka, Yamada, Tripathi, Jorne, Vou, Romero-Talamas, Izzo)

My Recent Study about Turbulent Reconnection

• Talk at MR2003

• Internal shocks created by some instabilities and Turbulence in the reconnection jet

Turbulent Reconnection• Matthaeus & Lamkin 1985, Phys. Fluids, 28, 303,

‘Rapid magnetic reconnection caused byu finite amplitude fluctuations’

• Matthaeus & Lamkin 1986, Phys. Fluids, 29, 2513, ‘Turbulent magnetic reconnection’

• Enhanced viscous and resistive dissipation

Turbulent Reconnection

Coronal Heating by Turbulence

• Matthaeus et al. 1999, ApJ, 523, L93, ‘Coronal heating by magnetohydrodynamic turbulence driven by reflected low-frequency waves’

Reconnection Rate Enhanced by Turbulence

• Vishniac & Lazarian 1999, ApJ, 511, 193, ‘Reconnection in the interstellar medium’

• Lazarian & Bishniac, 1999, ApJ, 517, 700, ‘Reconnection in a weakly stochastic field’

Reconnection Rate Enhanced by Neutral Gas

• Cho, Lazarian, & Vishniac 2002, ApJ, 564, 291, ‘Simulations of magnetohydrodynamic turbulence in a strongly magnetized medium’

• Yan & Lazarian 2003, ApJ, 592, L33, ‘Grain acceleration by magnetohydrodynamic turbulence: Gyroresonance mechanism’

• Cho, Lazarian, & Vishniac 2003, ApJ, 595, 812, ‘Ordinary and viscousity-damped magnetohydrodynamic turbulence’

• Many papers are posted in astro-ph.

MHD Simulations of Turbulent Reconnection

• In Yokoyama-san’s results, the reconnection rate is not enhanced.

• They are same with Tanuma’s results.

• Much more simulation grids would be required.

Particle Acceleration in Analytic Reconnection Current Sheet• Craig & Henton’s analytic solution(Craig &

Henton 1995, ApJ, 450, 280)

• Hirose, Litvinenko, Shibata, Tanuma et al. (2003): MHD simulations of stability.

• Heerikhuisen, Litvinenko, & Craig (2002), ApJ, 566, 512, ‘Proton acceleration in analytic reconnecting current sheets’: Test particle in Craig & Henton solution

• Takasaki, Asai, et al.: Test particle in Craig & Henton solution

Craig & Henton(1995)’s Solution

Numerical Test of Stability• Hirose, Litvinenko, Shibata, Tanuma et al. (2003)

examine stability of Craig & Henton solution by performing MHD simulations.

• It is revealed that Craig & Henton solution is unstable to tearing instability or Kelvin-Helmholtz instability in some cases.

Particle Acceleration in Analytic Solution

• Heerikhuisen, Litvinenko, & Craig (2002), ApJ, 566, 512, ‘Proton acceleration in analytic reconnecting current sheets’: Test particle in Craig & Henton solution

Trajectories of Test particles

Spectrum of Test Particles

Particle Acceleration in Turbulence• Dmitruk, Matthaeus, Seenu, &

Brown 2002, ApJ, 597, L81, ‘Test particle acceleration in three-dimensional magnetohydrodynamic turbulence’

MHD Equations

Simulations• Mach number is 0.25.

• Specific heat ratioγ=5/3

• The random fluctuation is assumed at 1<k<4.

• R=Rm=1000

• Pseudospectral code (Ghosh, Hossain, & Matthaeus 1993)

• The resolution is 256^3 Fourier modes.

Ohm’s law

Results• Turbulent |B| (upper) and |E|

(lower). Yellow shows high, blue shows low.

• The energy spectrum of the MHD fields (not shown in the paper) is consistent with a Kolmogorov 5/3 power law.

Nonrelativistic Equations of Motion

• α=Ωi Ta relates the turbulent field scales with the particle motion scales. In general, α>>1: turbulent time scale is much slower than gyro frequency. In this paper, α=10^2, 10^3, 10^4, 10^5.

• Ωi=qi B/ mi c is normalized gyro-frequency.• 50000 particles• Runge-Kutta 4th order.

Trajectories• 100 test particles (out of 50000)

• The color shows velocity.

Particle Energy Distribution

-2

-0.6

Emax and <E> v.s. α

• Emax=2αE||λ||• Solid line: This simulation• Dotted line: Particle simulation• Dashed line: Integration

Emax

<E>

Emax• Emax=2αE||λ||∝ vBL.

• These results are consistent with Swarthmore Spheromak laboratory reconnection experiment (Brown et al. 2002, ApJ, 577, L63) and a wide range of space and astrophysical systems (Makishima 1999, Astron. Nachr., 320, 1997Proc. Of ASCA 4th Meeting)

Particle Simulations• Tanuma et al.

• Nishikawa et al. 2003

• To obtain spectrum.

• Naito: Monte-Carlo simulations

Summary• Report of conferences

• Turbulent reconnection

• Particle acceleration

• Particle simulations