Main task Understanding fundamental processes in space plasmas: shock waves, turbulence, reconnection Applications in Sun, heliosphere, and magnetospheres.

IWF/ÖAW

Main task Understanding fundamental processes in space plasmas: shock waves,

turbulence, reconnection Applications in Sun, heliosphere, and magnetospheres

Main research topics

1. Space-time structure of shocks and turbulence Theoretical model construction Comparison with multi-point observations

2. Waves and reconnection Wave mode identification Condition and mechanism of reconnection

Refereed publications (since Jan 2013) Total: 15 (first author: 7)

Educational activities (since Jan 2013) Lecturing at TU Braunschweig, teaching at Ilia University (Georgia)

Space Plasma Physics: Heliosphere

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IWF/ÖAW

Lead: Yasuhito Narita

Members

Staff: P. Bourdin, N. Dwivedi, C. Möstl, Z. Vörös, T. Zaqarashvili

PhD Student: T. Rollett

Cooperation within IWF

Magnetospheric dynamics (Nakamura et al.)

Heliospheric dynamics (Lammer et al.)

MMS high-frequency magnetometer data (Magnes et al.)

Solar Orbiter wave data (Steller et al.)

Key international collaboration

Germany: TU Braunschweig; Italy: INAF-IAPS Rome; Romania: ISS Bucharest; Spain: UIB; USA: Johns-Hopkins University

Who are we?

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IWF/ÖAW

CME-CME interaction

Double-CME event in July 2012

Imaging and in-situ observation

Lesson for extreme events

CME-shape and trajectory

Global shape of shocks and flux ropes

Self-Similar Expansion model

Multi-point imaging

CME prediction

Evolution scenario of CME

Prediction of CME hit on the Earth

3

Shock Waves

Liu et al. (2014)

Davies et al. (2013)

IWF/ÖAW

Space-time structure

Analytic treatment of Navier-Stokes eq.

Wavenumber-frequency spectrum

Doppler shift and broadening

Breakdown of Taylor's frozen-in flow hypothesis

Impact on solar wind turbulence research

Error estimate for Kolmogorov constant

Collaboration with Johns-Hopkins Univ.

4

Turbulence Theory

Narita (2014)

Wilczek et al. (2014)

IWF/ÖAW

Solar wind as a natural turbulence laboratory

Wave mode identification

Combination: Observation, simulation, and analytic theory

First-time evidence for ion Bernstein wave in the solar wind

Collaboration with TU Braunschweig

Wave Picture of Turbulence

5

Narita (2014)Comisel et al. (2013)Perschke et al. (2013)

Cluster observation Numerical simulation Analytic theory

IWF/ÖAW

Current sheet thickness

Fitting with the Harris-type sheet

Capon's inverse method for Cluster data

Collaboration with Nakamura et al.

Turbulent-reconnection hypothesis

Dispersive wave triggering

Whistlers and kinetic Alfvén waves

Large-scale simulation (MHD and ion-scale)

6

Current Sheet and Reconnection

Narita et al. (2013)

IWF/ÖAW

Filament formation

Isotropy restoration in high-beta limit

Confirmation by ion PIC simulation

7

Structure Formation

Zaqarashvili et al. (2014)

Cluster observationNumerical simulation

Narita et al. (2014)

Flux-tube formation

Twisted tube model construction

Comparison with spacecraft data

IWF/ÖAW

MMS Mission (2015+)

Turbulent-reconnection hypothesis

Heating mechanism in turbulence

Particle acceleration mechanism

Large-scale simulation (fluid to particle scale)

Reconnection simulation

Turbulence simulation

Sun and heliosphere

CME modeling and impacts on planets

Solar wind turbulence

Corona heating

Solar Orbiter (2017+)

Future: 2015-2018

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IWF/ÖAW

Thank you

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