Detector

Monoenergetic proton backlighting for studying field evolution and areal density in HEDP

R. D. Petrasso, MIT

3 MeV

0 5 10 15 20

MeV

Pro

ton

Yie

ld DD D3He

Detector

Detector

0.6 ns after laser on

15 MeVLaser

MITMIT

Summary

MIT NLUF radiographs show details of magnetic field structure and time evolution during and long after laser illumination.

Data and LASNEX are in general agreement with the laser on, but diverge afterwards

Monoenergetic proton backlighting is being used for studying field evolution and ρR in HEDP

Important opportunities exist for studying:

Imploded capsules Plasma plumes/jets Laser-hohlraum interactions Plasma stopping power

MITMIT

Collaborators

C. K. Li F. H. SéguinJ. A. FrenjeJ. R. Rygg

R. D. Petrasso

MIT

R. P. J. TownP. A. AmendtS. P. HatchettO. L. Landen

A. J. MackinnonP. K. PatelM. Tabak

LLNL

J. P. KnauerT. C. Sangster V. A. Smalyuk

LLE

0

5

0 5 10 15Energy (MeV)

Yie

ld /

Me

V (

X1

0 10)

D3He p(x100)

DDp

T3He D

( 100)

DT

Multiple mono-energetic particles can be matched to the fields and ρR of an HED experiment

OMEGA shot 14972

ρR : ~ 5 to ~ 300 mg/cm2

rgyro : differ by ~ X 5

A monoenergetic, isotropic source has been used for multiple, simultaneous experiments at OMEGA

mesh

“Backlighter”

Backlighter drive beams

CR-39

Interaction beam

CH foil

side-on

face-on

0.3 ns 0.6 ns 0.9 ns 1.2 ns 1.5 ns 1.8 ns 2.3 ns 3.0 ns

Submitted to PRL, Li et al.

DATA

Interaction laser on for 1 ns

Data and LASNEX are similar with the laser on, but diverge afterwards

LASNEX

0

250

0 1 2 3

Time (ns)

0

0.6

Bdℓ (MG-µm)

Laser power (TW)

Field amplitudes from data and LASNEX are similar with the laser on, but diverge afterwards

laser

LASNEX

data

After laser pulse, experimental magnetic diffusivity is larger than LASNEX

0.3 ns

0.6 ns

0.9 ns

1.2 ns

1.5 ns

1.8 ns

2.3 ns

3.0 ns

0.3 ns

0.6 ns

0.9 ns

1.2 ns

1.5 ns

1.8 ns

2.3 ns

3.0 ns

Future HED experiments will utilize monoenergetic, multiparticle, isotropic backlighters

Magnetized-Target fields and ρR

Fields and ρR in implosions – R. Kingham, CO3 :PDD

Fields of OMEGA-EP / NIF-ARC laser systems Fields in hohlraums

Fields and modulations in RT experiments

Plasma stopping power

Magnetized-Targetfields and ρR (Nov. 2006)*

D3He implosion proton backlighter

B 10 MG

Laser beams

Laser beams

APS talk by O. V. Gotchev et al., JO2.00012

B fields generated by a ring of beams around an Au tube(Feb. 2007, Fusion Science Center)

AuProtons

CH

Side view Top view

Cartoon image

Detector

Mesh

D3He backlighter

Fields and ρR in cone-capsule, FI implosions

Fields generated by EP-plasma interactions

mesh

“Backlighter”

Backlighter drive beams

CR-39 detector

CH foil

OMEGA EP beam

We are proposing similar experiments for NIF-ARC.

Fields from rings of laser beams in a hohlraum(MIT NLUF experiments in 2007)

Li et al., RSI (2006)

Uniform plasma

Te ~ 50 eV

ne ~ 1023 /cc

~ 100 m

D3He implosion proton backlighter

Stopping power in dense, cold plasmas

Li et al., RSI (2006)

MITMIT

Summary

MIT NLUF radiographs show details of magnetic field structure and time evolution during and long after laser illumination.

Data and LASNEX are in general agreement with the laser on, but diverge afterwards

Monoenergetic proton backlighting is being used for studying field evolution and ρR in HEDP

Important opportunities exist for studying:

Imploded capsules Plasma plumes/jets Laser-hohlraum interactions Plasma stopping power