shockwaves and jets Dawei Yuan Group for Intense Laser High Energy - - PowerPoint PPT Presentation

Applying B fields on laser-produced shockwaves and jets

Dawei Yuan

Group for Intense Laser High Energy Density Physics

Institute of Physics, Chinese Academy of Sciences

LaB workshop @ LULI, 2013-12-04

1Beijing National Laboratory for Condensed Matter Physics, Institute of Physics,

Chinese Academy of Sciences, Beijing 100190, China

2National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012,

China

3Institute of Applied Physics and Computational Mathematics, Beijing 100094, China 4Institute of Laser Engineering, Osaka University, 2-6 Yamada-oka, Suita, Osaka, 565-

0871, Japan

5Research Center for Laser Fusion, China Academy of Engineering Physics, Mianyang

621900, China

6National Laboratory on High Power Lasers and Physics, Shanghai, 201800, China 7Key Laboratory for Laser Plasmas (Ministry of Education) and Department of

Physics, Shanghai Jiao Tong University, Shanghai 200240, China

Collaborators:

Content:

• Collisionless shockwave generation at Shengguang-II(SG-II) laser

facility  Showing results at SG-II in recently years Discussion about results

• The factors (Ambient medium, Radiation cooling, Magnetic field)

effect on the jet collimation in Lab  Jet deflection by crosswind produced by hot plasma Weaker B field effect on jet collimation

Collisionless shockwave

Plasma Phys. Control. Fusion 50 (2008) 124057 (15pp) Nature Physics/Published online: 6 October 2013

Source of sun-wind Collisionless shockwaves are observed in supernova remnant and sun- earth space, etc. Origin of cosmic ray

Supernova Remnant SN1006

Collisionless Shock CME

Plasma Phys. Control. Fusion 50 (2008) 124057 (15pp)

• Phys. Plasmas 15, 082108 (2008)

(a) (b)

Collisionless shockwave

Filamentary Two-stream Weibel Two types model experiment 1) One-direction laser irradiation 2) Counter-beam irradiation The fields via these instabilities supply the necessary dissipation processes for shockwave generation.

Collisionless shockwaves generated at SG-II laser facility

Shenguang II

SG II 9th beam used as probe beam, 50mJ, 30fs pulse duration, @ 2 (527nm) .

Experimental setup

SG II 8 main laser beams with 2 kJ total energy, 1ns pulse duration, @ 3  (351nm) The laser intensity: ~4×1015 W/cm2 The delay time range between main beam and probe is from 0 ns to 15 ns.

Collisionless shock generation in experiment (2009)

5 ns 9 ns

Density jump The ion mean free path is ~25-35 mm，far larger than the density jump region (100μm) Collisionless shock

• T. Morita et al. Phys. Plasmas 17, 122702 (2010)

First model-Laser irradiation single CH foil

Evolution of two counter-streaming plasmas(2009-2010)

1 ns 5ns 9 ns 3ns 2 ns

• D. W. Yuan, et al., High Energy Density Physics 9 (2013) 239-242
• X. Liu, et al., New J. Phys. 13 (2011) 093001

Electrostatic shockwave Weibel-driven-shockwave ? Shockwave decay Ion-Weibel instability ?

T1 T2 T3

Laser irradiation pair of CH foils

Weibel-instability observed in experiment (2011 + 2012)

We confirm that this filaments appear at around 5ns in experiment(repeat it every year)

YUAN Dawei et al. Sci China-Phys Mech Astron 56 (2013) 12:1-5

5ns 5ns Symmetrical laser irradiation Left:4 beams Right:4beams

Non-symmetrical laser irradiation

Left: 3beams Right: 4beams

Evolution of two counter-streaming plasmas(2009-2010)

1 ns 5ns 9 ns 3ns 2 ns

• D. W. Yuan, et al., High Energy Density Physics 9 (2013) 239-242
• X. Liu, et al., New J. Phys. 13 (2011) 093001

Electrostatic shockwave Weibel-driven-shockwave ? Shockwave decay Ion-Weibel instability ?

T1 T2 T3

Firstly observing two shockwaves generation in experiment (2013) (Preliminary results)

y=190

1.4 e19 5.165 e19

200 μm

580

S1 S2

y=190

120 μm 96 μm

6.417 e19 2.742 e19 6.14 e19 559 519

S1 S2

X Y X Y

8 ns 10 ns (a) (b) (c) (f) (e) (d)

The linear dispersion relation of the electrostatic mode:

))) ( 1 ( ) sin ( 2 ) ( ( ) (

2 , 2 , 2 2 2

    



s s s s d s s s th Ds

Z V Z v k kc      

The linear growth rate of the elec- trostatic ion-ion instability(ESI) The linear growth rate of the electro- magnetic Weibel-type instability(WBI)

200 400 600 800 1000 1200 1400 1600 50 100 150 200 250 300

Temp.(eV)@3 ns X(um) ion Temp. electron Temp.

100 200 300 400 500 600 700 800 900 1000 100 200 300 400 500

Temp.(eV)@2 ns X(um) ion Temp. electron Temp.

Target position

Time: ESI is easy to grow up at early stage(before 3 ns), because of the large temperature difference between electron and ion WBI appears at later time(after 3 ns). Space: ESI:~electron inertial depth-~de = c/ωpe ~5 -7 μm « space resolution limit. WBI:~ion inertial depth~ di = c/ωpi ~ 100 μm.

Discussion

Temperature distribution

• From calculation and simulations, it is deduced that the density jump at early

time was probably an electrostatic collisionless shock@2 ns.

• The length of the filaments observed at later time (for example, 5 ns) which is

near to the ion inertial depth. The filaments should be caused by the Weibel instability.

Discussion

• W. Fox et al. [Phys.Rev.Lett. 111,255002 (2013)

Filamentation Instability of counterstreaming Laser-Driven Plasmas

Conditions: SG-II laser facility Total energy:2.0 kJ Laser pulse: 1 ns Wavelength: 3ω 351 nm Targets material: CH Targets separation: 4.5 mm Conditions: OMEGA EP laser facility Total energy:3.6 kJ Laser pulse: 2 ns Wavelength: 3ω 351 nm Targets material: CH Targets separation: 4.5 mm Optical diagnostics Sensitive to density Insensitive to Electromagnetic field Proton radiography technique Insensitive to density Sensitive to Electromagnetic field

• D. W. Yuan, et al., High Energy Density Physics (2013)

YUAN Dawei et al. Sci China-Phys Mech Astron (2013)

• W. Fox et al. Phys.Rev.Lett. (2013)

t = 5 ns

Discussion

CH CH CH CH

Content:

• Collisionless shockwave generation at Shengguang-II(SG-II) laser

facility  Showing results at SG-II in recently years Discussion about results

• The factors (Ambient medium, Radiation cooling, Magnetic field)

effect on the jet collimation in Lab  Jet deflection by crosswind produced by hot plasma Weaker B field effect on jet collimation

Astrophysical jet

Physics of jet launch and acceleration

• --Constrain the initial condition for jet production

Physics of jet collimation, propagation and termination

• --Collimation is due to the internal outflow properties or to an

interaction with the environment.

• Ambient Medium jet deflection via hot plasma
• Radiation cooling Different materials
• Magnetic field

Jets are axially collimated outflows, which are ubiquitous in astrophysics, such as YSOs, AGNs and BH.

Jet deflection via hot plasma wind(2012)

Figure (a) shows the impact of the crosswind on the jet in lab, which is determined by mean free path of the wind ions interacting with the jet. For the electron density in the jet of ne >5 * 1018 cm-3 and ionic charge Z >5, one finds λwj < 2 * 10-3 cm. Thus, λwj/Rj «1, it is appropriate to use the two-dimensional hydrodynamic numerical simulations. Figure (b) shows the corresponding simulation result at the same delay time with LARED -S codes

Jet deflection via hot plasma wind(2012)

We also change the property of crosswind by changing the time difference between laser 1/2 and laser 3. The result indicates that the deflection jet depend on the property of the hot crosswind.

Jet collimated via extra B field(2013) (Preliminary results)

B

B

~1.6mm ~1.1mm ~1.1mm L: 1600 μm R: 200 μm L: 1100 μm R: 200 μm L: 1100 μm R: 80 μm

15 mm 0.8 mm 0.8 mm 0.4 mm 0.05 mm

Permanent magnet(PM)

15 mm 0.8 mm 0.8 mm 0.4 mm 0.05 mm

PM PM

15 mm 0.8 mm 0.8 mm 0.4 mm 0.05 mm

B~3000Gs ║ B~0Gs B~3000Gs ┴

(a) (c) (b)

length shorter Much narrower length shorter

T= 2 ns T= 2 ns T= 2 ns

Summary

• We study the evolution of the two counter-streaming flows.
• Electrostatic shockwave is observed during the evolution
• f the two counter-streaming plasmas.
• Filaments via Weibel-type instability is observed.
• Two shockwaves are firstly observed using two counter-

streaming plasmas in experiment.

• Jet is deflected by the hot plasma crosswind.
• Weak magnetic field (~kGauss)affect on the jet

collimation

shock Jet