nif and indirect drive inertial fusion target physics and...

JDL FESAC IFE 10/28-29/03

NIF and Indirect Drive Inertial Fusion Target Physics and

Applications to High Energy Density Physics

*Work performed under the auspices of the US Department of Energy by the Lawrence Livermore National Laboratory under Contract W-7405-ENG-48

John Lindl LLNL Fusion Energy Program LeaderSenior Scientist NIF Programs

Lawrence LivermoreNational Laboratory

University of California

Presented to:

FESAC Panel on the Status of IFE and HED

October 28-29,2003


Summary/Outline

NIF Early Light (NEL) is meeting its performance goals and experiments have begun with the first 4 beams

The ICF Program is making excellent progress on the baselineindirect drive ignition approach

Alternate indirect drive ignition target designs could allow muchhigher yields and target gains

The NIF indirect drive ignition program will provide the ignitiondata required for a range of drivers including HIF and Z-pinches

NIF is designed to test Direct Drive as well as Indirect Drive

The science of ICF targets is applicable to a wide range ofastrophysical phenomena


NIF will test much of the physics for a widerange of targets being examined for IFE

Heavy Ion Hybrid Target NIF Indirect DriveTarget

Double-ended Z-pinch

Heavy Ion DistributedRadiator Target

Heavy Ion Driver Laser Driver Z-Pinch Driver

Ignitor laserbeam

Fast IgnitionDirect Drive Target


• Demonstrate ignition and gain for both direct and indirect-drive and

possibly for fast ignition

• Provide key data on target chamber and target fabrication technologies

• Confirm predictive target modeling capabilities

The National Ignition Facility gives the U.S. a uniqueopportunity for demonstrating critical elements ofICF target physics required for IFE


Both indirect drive and direct drive illuminationgeometries can be accommodated by the NIF design

Irradiation configurations

Indirect drive

Direct drive

(Advanced technology for compact chirped pulse amplification (CPA) beingpursued to allow fast ignition on NIF)


NIF Target Chamber upper hemisphere


First four NIF beams installed on the target chamber

View from inside the targetchamber

Quad 31b beamtubes and optics areinstalled and operational


Target positioner and alignment system insidetarget chamber


NIF has begun to commission its experimentalsystems

The NIF Early Light (NEL) commissioning of four laser beams hasdemonstrated all of NIF’s primary performance criteria on a per beambasis

— 21 kJ of 1ωωωω light (Full NIF Equivalent = 4.0 Mjoule )

— 11 kJ of 2ωωωω light (Full NIF Equivalent - 2.2 Mjoule) - used baseline3ωωωω crystals not optimized for 2ωωωω

— 10.4 kJ of 2ωωωω light (Full NIF Equivalent = 2.0 MJoule

— 25 ns shaped pulse

— < 5 hour shot cycle (UK funded)

— Better the 6% beam contrast

— Better than 2% energy balance

— Beam relative timing to 6 ps

Initial Experiments on Laser Plasma Interaction are being carried out


NIF will map out ignition and gain curves formultiple target concepts

— Fast ignition potentially gives more gain and lower thresholdenergy but the science and technology is less well developed

FI at NIF

T ρ

Conventional ICF

Intensity ~1014 - 1015 w/cm2

Fast�injection�of heat

T

r

ρ

Fast Ignitor

Intensity ~1020 w/cm2

Indirect Drive

AdvancedIndirect

Drive on NIF


The US Indirect Drive ICF Program is based on anextensive data base developed on the Nova andOmega Lasers

• Laser-Target Coupling: U.V. lasers with smoothing gives excellenttarget coupling on Nova and Omega experiments - comprehensivepredictive modeling has not been achieved

• Symmetry: X-ray Drive experiments (Nova and Omega) show adequatesymmetry Pn(t) and ∫Pn(t)dt

• Hydrodynamic Instabilities: Quantitative Rayleigh-Taylor experimentsshow adequate reduction in γ because of flow and ∇ρ effects

• Integral Implosions: Implosions on the Omega laser, using a NIF-likeIllumination geometry, perform at near calculated levels forconvergences greater than 20

• Numerical Modeling: Hohlraum (symmetry and energetics) andhydrodynamic instability experiments, as well as integral implosionexperiments are well-modeled by 2D and 3D radiation-hydro codes


The NIF baseline indirect-drive target absorbs1.35 MJ and produces a yield of 15 MJ, indetailed calculations


Development of cryogenic targets are acentral challenge for ignition on NIF

08-00-1299-2932.ppt12JDK

Cooling ring

Heater ring

5.5 mm

Heat-flow �coupler

HOHLRAUM

Cryostat

Cooling ring

2-mm capsule�beryllium or �polymer

Solid D-T �fuel layer��

1-µm polyimide�window

• Sufficiently smooth Deuterium-Tritium fuel layers have been formed

• We have fabricated three types ofcapsules

• Surface finishes meetingrequirements have been achieved(for CH and PI and for gradeddopant Be)

• Development of cryogenichohlraums is underway

• Scientific prototyping of thecryogenic systems has started


HYDRA now hasall the physicsnecessary to do3D non-LTEintegratedhohlraumsimulations, aswell as 3Dcapsuleimplosions

3D hohlraum simulation withall of the beams, in NIFindirect drive configuration

We are doing 3D simulations of bothhohlraums and capsules


Several design modifications resulted from 3Dcalculations:

•Increased LEH thickness

•Decreased gas fill density

•Adjusted power balance between cones

•Repointed inner cone beams to reduce m=4

•Moved outer cone to reduce P4

Resulting implosion hasrms deformation of hot spotat bang time 3 µm, factor oftwo safety margin

We now have a hohlraum design optimized in3D with very nice 3D symmetry


Capsule-onlysimulations w/asymmetry andfabrication perturbations

A few of these havebeen done, including arecent simulation with:

•3D asymmetry inferredfrom integratedsimulation

•Nominal “at spec”perturbations on ice andablator in low,intermediate, and highmodes

•Gave 21 MJ (90% of 1Dcalculation)

Ignition time140 ps beforeignition time

400 g/cc density isosurface (different scale)

60 g/cc density isosurface

Poly/DTinterface

Hohlraumaxis

Stagnationshock

Polyimide Capsule 3D calculations have bothasymmetry and surface roughness


Be next to fuelis undoped,dopant rises tomax in twosteps andback downagain

0.35%0.7%

0.35%

848928

1105 µm

934940 995

1011

0.0%

Cu(%)

300 eV design:

200

Initial ablator roughness(rms, nm)

0

5

10

15

20

25

Yield(MJ)

Polyimidecapsule

Surfaceachieved with PI

400 600 8000

300 eV graded-dopedBe(Cu) design, at same

scale

New capsule designs using Be with graded Cudopant are spectacularly robust

Be

DT

0.0%


Typical energy flow in an igniting ICFhohlraum/capsule


0

10

20

30 NIF PointDesign

11%

22-26%seems possible

Improvements possible for a 250 eV capsule design

A combination of many small effects may allow adoubling of the hohlraum coupling efficiency


More energy allows largercapsules which require lowerradiation temperatures

Lower temperatures implylower laser intensitiesconsistent with LPIconstraints based on currentunderstanding and initialOmega experiments

NIF’s green light capability may allow muchlarger capsules and yields


Target Fabrication•Capsules•Cryo layering in hohlraums

Target Design

Diag. techniq.,initial tuning

96 beam tests,2-cone tuning Final

symmetrytuning

Integrated 96beam tests

Optimize Tr

Diag.techniques

Implosion Diagnostics

Shock timing

Ablator tests Final shocktiming

Ignition campaign

Sub-scale& full scalenon-cryo implosions

Firstcluster

& 8-fold2-cones Full NIF

40-00-0997-1989S23BVW/cld

40-00-0997-1989H23RHS/cld 40-00-0997-1989P

23BVW/cld

Beams: 4 48 120 192

Ignition

Large Plasma Experimentswith beam smoothing

Symmetry measurement & controlHigh Convergence Implosions

Shock Timing diag. developmentAblator characterization

Omega

Optimize beam smoothing

Symmetry

IgnitionImplosions

Shock Physics

10 11 120907FY02 03 04 05 06 08

Cooling ring

Cryogenic fuel layer

Capsule ablatorHeater ring

Heat-flow coupler

He + H2 fill

Heat-flow coupler

HOHLRAUM

Cryostat

Cooling ring

13

Trad diagnostic techniquesHohlraumEnergetics

Firstquad

MP-1a

The indirect drive Ignition Plan makes use of existingfacilities, and early NIF, to optimize the ignition design


The physics issues for ion beam target design forIFE and NIF targets have much in common

• Capsule physics (hydrodynamics, ignition, and burn propagation)

• Symmetry control

• Hohlraum energetics

Yield = 400 MJDriver (using NIF-like hohlraum to capsule radius ratio)

6 MJ of 4 GeV Pb ions �� gain 677.5 MJ of 8 GeV Pb ions �� gain 53

Capsuleablator

Cryogenicfuel layer

Heat-flowcoupler

Heaterring

Coolingring

Heat-flowcoupler

Cooling ring

Laser beams

Fe-foam radiator

Gaussian ion beamsFoot pulse beams (3 GeV)Main pulse beams (4 GeV)Au foam

Radiation case

Au foam radiatorCapsule(Be ablator)

He-gas fill

2.7-mm “effectivebeam radius

NIF target HIF Target


New symmetry control techniques allow targetdesigns with larger spots for distributed radiatortargets for heavy ion fusion

Shine shields tocontrol Legendre

mode P2

Shim tocontrol early

time P4

Pressure balanceholds position of

radiators

Beam spot: 3.8 mm x 5.4 mmEffective radius: 4.5 mm6.7 MJ beam energyGain = 58

(NIF-like baseline symmetry control)Beam spot: 1.8 mm x 4.1 mmEffective radius: 2.7 mm5.9 MJ beam energyGain = 68

These symmetry control techniques can be testedon Z or Omega and ultimately on NIF

Distributed radiator targetHybrid target


Z double-pinchhohlraum

3.3 mm

4.5 mm

4.7 mm

Capsulediameter: 2.15 mm

Secondary hohlraumRadius ≡≡≡≡ RsecLength ≡≡≡≡ Lsec

P4 vs. length and capsule size6.7 keV backlit images

Time-integrated P4 depends more strongly on capsule size than on hohlraum length

Predicted P2 = 0, P4 = - 5% at Lsec / Rsec = 1.75 to be tested in September shot series

Thin-shell capsules in double z-pinch hohlraumsprovide null cases for P4 shimming tests


Density contours

Calculations of the proposed Z experiment showthat a shim can take out the P4 asymmetry


Shape of the imploded shell near ignition time

Calculations of the HIF Hybrid Target with ashim layer show the improvement in symmetry


A wide range of capsules for Fusion Energyapplications have stability and symmetryrequirements comparable to NIF targets

• The target size appropriate for the first average fusionpower facility in the IFE development plan

Scale

Peak TR

IFAR

Convergence Ratio

Energy Absorbed (kJ)

Yield (MJ)

ETF

246

46

37

631

171

Reactor (6Hz)

223

42

36

1128

381

Reactor (3Hz)

203

35

40

1841

830

• Enhanced NIF capsulesmay reach this scale

NIF

300

45

36

150

15


The NRL target for KrF driven IFE uses wetted foamdirect drive targets with zooming and a picket pulse


Wetted foam and “All DT” Direct Drive target designsare being explored for NIF


With appropriate beam pointing it may be possibleto achieve Direct Drive Ignition on NIF with the

Indirect Drive beam configuration


ICF scientific issues are relevant to high energydensity phenomena in Astrophysics


A wide variety of astrophysics phenomena can beinvestigated with experiments on intense lasers


Summary/Outline

NIF Early Light (NEL) is meeting its performance goals and experiments have begun with the first 4 beams

The ICF Program is making excellent progress on the baselineindirect drive ignition approach

Alternate indirect drive ignition target designs could allow muchhigher yields and target gains

The NIF indirect drive ignition program will provide the ignitiondata required for a range of drivers including HIF and Z-pinches

NIF is designed to test Direct Drive as well as Indirect Drive

The science of ICF targets is applicable to a wide range ofastrophysical phenomena


Backup Viewgraphs


Why do we believe that ignition will work on NIF?

• Numerical simulations provide a first principles description of x-ray targetperformance (except for laser-plasma interactions which are expected to besmall for scaled NIF plasma conditions and beam smoothing

• Predictions for NIF target gain have not changed qualitatively since 1990,despite 13 years/15,000 experiments on Nova, Omega and Nike to comparewith codes

• The Halite/Centurion experiments using nuclear explosives havedemonstrated excellent performance, putting to rest fundamental questionsabout basic feasibility to achieve high gain

Halite/Centurion

NIF igniton

Nova, Omega

Energy

Power


The goal of the target design work is toidentify the optimal targets for a broadspectrum of possible approaches to IFE

Target Requirement HED Scientific Issue Power Plant Impact

Power/Energy

Pulse shaping/pulse length

Beam geometry

Target Material(hohlraum/capsule)

Target Precision

Spot size/Intensity

Drive TemperatureSymmetryStability

Fuel adiabat/EOS

Symmetry/RadiationTransport

Wall albedo …Coupling Efficiency

Capsule Stability

Hydrodynamic InstabilitySymmetry

Drive TemperatureStability

Transport/Focusing

Driver Beam QualityDriver Cost

Driver Beam Conditioning

Chamber DesignWall Protection Approach

ES&HManufacturing

Manufacturing

Optics and ChamberDesign


Ion target

Ionbeams

Radiationconverter

Direct drive

Ablator (low-Z foam or solid)

Gaseous fuel (atvapor pressureof solid or liquid fuel)

Solid or liquid fuel

Indirect drive

Advantage:• High coupling efficiency• Reduced Laser Plasma

Interaction effects

Advantages:• Relaxed beam uniformity• Reduced hydrodynamic instability• Significant commonality for lasers and ion beams

The principal approaches to ICF utilize direct driveor indirect drive implosions to compress the fuel

Laser target

Laser beams

Low-Z gasHohlraum


January 1977 January 2002

2D LASNEX and 2D/3D HYDRAInclude Arbitrary Lagrange Eulerian grid motion, material interface reconstruction,multigroup diffusion and realistic radiation transport, charged particle diffusion, laser raytrace, Lee and More conductivities,XSNQ and online opacity servers, QEOS,EOS tables - SESAME, LEOS…•Basis interface, Yorick postprocessing•MPI parallel with threads - both have run onover 1600 processors

HYDRA 104 MFLOPS / processor on IBMWhite x 640 processors (8% of machine)67 GFLOPS (x 16750)

2D LASNEXLaser raytrace, multigroup diffusion, suprathermal electrons, MHD, charged particle diffusion, ionspecies diffusion, XSNQ, EOS tables

LASNEX 4 MFLOPS on CDC 7600

•Direct simulations of multimode surfaceperturbation growth 2D/3D, to 16.8 million zones•First full 3D simulations of NIF ignition hohlraumran 1 week, 1 million zones, 4.8 million photons•Full 3D capsule simulation of drive asymmetry4.4 million zones

•Capsule instability analysis: 1D sim. postprocessed with Artic, or 2D single mode •First 2D hohlraum simulations with capsule ~1500 zones, ran for weeks

Aggressive use of advanced computation hasbeen a hallmark of the ICF Program


Lasnex is a highly versatile computer code with awide range of physical models for processesimportant to ICF

Laser light:~3D ray tracing~1D EM wave

Electrons:~Thermal conduction (FD&FE)~Non-local conduction~Multigroup diffusion

Radiation (multigroup):~Frequency dependent sources~Diffusion (FD&FE)~Transport eqn.

Atomic physics (LTE&NLTE):~Average atom (XSN)~SCA~DCA~Tabulated opacity (LTE)~Tabulated EOS (LTE)~Inline LTE EOS

Hydrodynmics (2D):~Langrangian (quads)~Semi-Eulerian (SALE)~Slide lines

Ions:~Thermal condution

Burn products (n, γγγγ, CP):~TN reaction source~Multigroup diffusion


With Nova, the ICF program brought together advancesin laser performance, precision diagnostics, andadvanced modeling tools required for ICF to become amature quantitative scientific effort

— Nova was a 10 beam laser capable of producing 40 kJ of laserenergy at 0.351 µµµµm


Key results from the Nova program establishedthe specifications for NIF

• Hohlraums can achieveadequate symmetry and 10-25%coupling with multiple cones ofbeams

• Precise pulse shaping can beachieved as required for Fermidegenerate compression

• Hohlraums with pulse shapingare limited to ~300 eV with0.35 µµµµm lasers (I ~2x1015 w/cm2)

• Hydrodynamic instabilities limitshell to R/∆∆∆∆R ~35

200

100

10

1

0.2

Capsule energy gain plotted versus compression

Compression (X liquid density)102 103 104 105

Th

erm

on

ucl

ear

ener

gy

Cap

sule

ab

sorb

ed e

ner

gy

500

50

5

0.5

Capsule energy (KJ)for 15% implosion

efficiencyNIFIncreasing Pressure and

stability requirements


Advanced diagnostics have been central to measuringthe phenomena critical to understanding NIF

1.6 ns

1.9 ns

2.2 ns

2.5 ns

time

time

Sequence of x-ray backlitimages of imploding capsuleGated MCP x-ray imager

Pinholes MCP +film pack

Gatingelectronics

1 m

MCP gated imagers were operated between 100 eVand 10 keV with 5-50 µm, 30 -300 ps resolution

300µm


— Unequal absorption between conescan spoil beam balance

— Beam bending, beam spray and crossbeam effects can spoil symmetry

— Backscatter reduces laserabsorption and energycoupled into the capsule

The choice of laser wavelength is central tothe ICF Indirect Drive Ignition Program


• There is a wavelengthdependent maximumhohlraum temperaturedetermined by laser-plasma interaction -shown by lines labeled2ωωωω and 3ωωωω

• There is a minimum TRthat is dictated bykeeping hydrodynamicinstabilities undercontrol. The reddashed linecorresponds to thosetemperatures neededfor a surfaceroughness of ~200Å

The ICF ignition region in power and energy isbased on constraints for LPI and hydrodynamicinstabilities


NIF’s 2w capability may provide an operatingwindow for larger capsules with yields muchgreater than the baseline


• 2ωωωω looks very appealing in Lasnex designs• Preliminary experiments are encouraging

There is a well established physics basis forignition at 3w and experiments are beginningto address critical ignition requirements for 2w


The Nova ignition physics program utilizedhohlraums and capsules which were scaled totest key issues

Capsules— hydrodynamic instability— implosion symmetry— pulse shaping— implosion dynamics

— hohlraum plasma condition— laser-plasma interaction— hohlraum drive— x-ray wall loss— x-ray flux symmetry

4

6

9

4

6

8 7

2740 µm

1400 µm

700 µm700 µm

700 µm

72 1

1

10 105

39

3-µm-thick-tungsten hohlraumTen-beam irradiationLaser energy ~18 kJ (total)Wavelength = 0.35 µmPulse length = 1 ns (FWHM)


We have validated our ability to model laserheated hohlraum drive against a broad rangeof experiments

Lasnex can predict hohlraum drive to +/- 10% in x-ray flux

Vacuum and gas-filled hohlraums with 2.2ns shaped pulses

(3:1 and 5:1 contrast ratio)

Scaling of peak drive temperatureDetailed TR

4 comparisonfrom a scale 0.75 hohlraum

1000

800

600

400

200

0-0.5 0.5 1 1.5 2 2.5 3 3.50

300

250

200

150150 200 250 300

Experimental peak Tr (eV)

Las

nex

pea

k T

r (e

V)

time(ns)F

lus[

GW

/sr]

Laser off


Implosion symmetry can be controlled by varying thehohlraum geometry


Face-on: StreakedModelData

Side-on: Streaked

Side-on: Gated

08-00-0593-1818B

The measured growth of planar hydrodynamic instabilitiesin ICF is in quantitative agreement with numerical models


Using a NIF-like Illuminaition Geometry on Omega,Implosion performance is in excellent agreement with

calculations


The target/driver combination for IFE must meet aminimum product of driver efficiency times gain (ηηηηG)

P P P P faGME

net gross driver gross= − = − −( )1 1ηη

ME ~ 40% where M is the blanket multiplication and E is the thermal toelectric conversion efficiency

ηη

ηη

ηη

G

G

> −

⇒

⇒

7 10 (recirculating power fraction of 25 - 35%)

< 10% > 70 - 100

< 35% G > 20 - 30

Laser

HI

A safety margin of a factor of 2 in target gain is important for making a casethat we can strongly defend

•

•

•

⇒ G > 140

G > 40

Laser

HI


Distributed radiator:"Baseline" target Close-coupled target:

High gain at low driver energy

CH capsule design:Easier target fab

Fast ignitor target:High gain with low

accelerator peak power

Ignitorbeam

Hybrid target:Large beam spot

Large-angle distributed radiator:Large beam entrance angle

We look at a broad range of target options tomaximize flexibility


Small spot sizes have high leverage to increasetarget gain and reduce driver energy

Ion beam characteristics:4 GeV Pb+ions

5.9 MJ input energy2.7 mm effective radius spotGain 70

Ion beam characteristics:3.5 GeV Pb+ions

3.3 MJ input energy1.7 mm effective radius spotGain 130


Callahan 6/2002

Need to balance low order Legendre modes:

- Source behind a shine shield and radiation flows around shield near zero of P2- Case-to-capsule ratio with or without a shim to correct P4

HI distributed radiator

NIF laser (2x scale)

Double-ended Z-pinch

HI hybrid target

- Sources at zeros of P4 and with strengths set to balance P2

Symmetry in indirect drive is controlled by theposition and strength of the sources


Concept for Z-pinch driven ICF target

Z-Beamlet radiograph

Z-Beamlet target

Z-Beamlet Laser

The LLNL Beamlet laser - NIF’s scientific prototype - is now operationalas a diagnostic backlighter source on Z at Sandia Albuquerque

• The intense x-ray backlighting available from Beamlet has imaged z-pinch implosionswith a resolution not previously available on Z

Substantial progress has been made on thesymmetry of z-pinch driven indirect drive targets


Substantial progress has been made on the symmetryof double z-pinch driven indirect drive targets

Z830

Z831

Z839

Z833

Time

Radius

Peak density ~40 g/ccCR >14

G. Bennett, M. Cuneo, R. Vesey

68-75 eV peak drive~10 kJ absorbed

Radius vs. time

Z-Beamlet target

Z-pinchWirearrays


Backlit Implosions on Z measure capsule convergenceand implosion symmetry


Ignition will be pursued either by heating some ofthe fuel during compression or by rapid injectionof energy into a precompressed cold fuel volume

• Central hot spot ignition relies on precise control of implosion symmetryand hydrodynamic instability

• Fast ignition would utilize new concepts in short pulse laser technologyand will require significant advances in the understanding of chargedparticle production and transport at ultra-high intensity

T ρ

Shock heated central spot ignitesa high-density cold shell

PHS ≈ Pc = ααααρρρρc5/3

Conventional ICF

Fastinjection

T

r

ρ

Fast-e- heated side spot ignitesa lower density, larger uniform

fuel ball PHS >> Pc

Fast Ignitor

Fastinjectionof heat(I~1020

w/cm2)(~10pspulse)

(I~1015 w/cm2)(1-10 ns pulse)


Fast ignition can utilize a re-entrant tube andcone to provide access for the ignitor beamto the imploded, compressed core:

Main laserbeams

Ignitor beam(s)(short pulse)

capsule(cryogenic)

hohlraum

A NIF-like scheme

Flexibility for compressiondriver: Lasers, ion beamsz-pinch (Tabak 1991)

Potential compatibility withliquid wall chamber


Experiments on Gekko XII have seen enhancedneutron output from fast heating of a directdrive target with a reentrant cone

Fast heating scalable to laser fusion ignition R. Kodama, et al., Nature 418, 923 (August 2002)

2.5 KJ compression pulse + (60-500), 0.5 ps fast heating pulse

Neu

tro

n e

nh

ance

men

t (a

.u.)

Neu

tro

n s

ign

al (

a.u

.)

10

0

5

200

100

0-200 -100 0 100 200

Ave

rag

e d

enity

(m

l-1)

0.5

02.25 2.35 2.45 2.55 2.65

1.0

Neu

tro

n y

ield

Heating laser power (PW)

Energy (MeV)Injection timing (ps)

10.1104

106

108


• Same driver and fuel assembly options

•Larger laser focal spot-easier to produce

• Simpler proton energy transport by ballistic focussing

Imploded Fuel

Laser Protons

• Novel physics of Debye sheath proton acceleration

M. Roth et.al. Phys Rev. Lett 86,436 (2000). Ruhl et al. Plas. Phys. Rep.27,363,(2001)

Temporal, et al.Phys Plasmas 9, 3102, 2002

Proton ignition is a newer concept avoiding thecomplexity of electron energy transport


-400 -200 0 200 400 600

-0.40

-0.30

-0.20

-0.10

0.00

0.10

0.20

0.30

0.40

0.50

0.60

0.70

0.80

Distance (microns)

Tim

e (

ns

)

480 500 520 540 560 580 600

071802#4 Hemisphere

-400 -200 0 200 400 600

-0.40

-0.30

-0.20

-0.10

-0.00

0.10

0.20

0.30

0.40

0.50

0.60

0.70

0.80

Distance (microns)

Tim

e (

ns

)

480 490 500 510 520

071802#5 flat foil

Recent 100TW,100fs expt. shows first evidence of ballisticproton focusing (to 50 µµµµm) and enhanced isochoric heating

-400 -200 0 200 400 600

-0.40

-0.30

-0.20

-0.10

0.00

0.10

0.20

0.30

0.40

0.50

0.60

0.70

0.80

Distance (microns)

Tim

e (

ns

)

470 490 510 530 550COUNT_0719_1727___x

50 µµµµm200µµµµm >400µµµµm

Streak images of Planckian emission


We have compared ignition and burn propagation for NIFcapsules and possible future high yield capsules

High yield capsule

NIF capsule

Radiation temperature = 300 eV 210 eVImplosion velocity = 4 x 107 cm/sec 3 x 107 cm/secCapsule absorbed energy = 0.15 MJ 2.0 MJCapsule yield ~ 15 MJ ~ 1000 MJ

CH + 0.25% Br + 5%O

DT solid (0.2 mg)

DT gas 0.3 mg/cc

1.11 mm

0.95

0.87

3.25mm

3.0

2.75

Be

DT solid(7.2 mg)

DT gas0.3 mg/cm3


Although NIF will not directly test full scale targets forIFE, NIF and high-yield capsules have almost identicalignition conditions and burn propagation physics

Burn propagationProfiles at ignition

0.2-MJ NIF capsule(yield ~15-20 MJ)

0.2-MJ capsule(yield ~1000 MJ)

0.2-MJ NIF capsule(yield =15-20 MJ)

0.2-MJ capsule(yield ~1000 MJ)

Ignition is defined as thethreshold of burn propagation

Burn s sustained by αααα-particledeposition above ignition threshold

ρρρρr (g/cm2) ρρρρr (g/cm2)

Ti (

keV

)

Ion

tem

per

atu

re (

keV

)12

8

4

0.2 0.4 0.6 0.8 1.0

103

102

101

100

10-1

0 1 2 3

ρρρρ


15. Fireball of Gamma-ray Bursts16. Cosmological Jets (Rel.)17. Weibel Instability in GRB18. Non-LTE QED at AGN Core

Laser-produced Relativistic Plasmas

13. Vishiniac Instability of SNRs14. X-ray Lasers in the Universe

9. Atomic Process in SNRs10. Stellar Jets11. Radiation Hydro. in Early Galaxy12. Photo-ionized Plasmas

8. Opacity Evolution of Stars etc. many

Atomic Physics and X-ray Transport

6. Hydro-instability in Neutrino- driven SN Explosion7. RT Instability of Eagle Nebula

5. RT Instability of SN Explosion

Hydrodynamic Instabilities

4. Collision-less Shocks and Particle Acceleration (Origin of Cosmic Rays)

3. Interaction of Molecular Cloud with Strong Shock by SNR (Morphology)

2.EOSGiant Planets

Hydrodynamics and Shocks

1. Non-local Transport of Neutrinos ina Baby Neutron Star

Electron Energy

Transport

C. ResemblanceB. SimilarityA. Sameness

A wide range of Laboratory and Astrophysical phenomenacan be characterized by their degree of correspondence


The Rayleigh-Taylor instability occurs when aheavy fluid (ρρρρH) “sits on top of” a light fluid (ρρρρL)

ρρρρH

ρρρρH

ρρρρH

ρρρρL

ρρρρL

ρρρρL

y

y

y

V

g

g

g

x

x

x

r ηηηηb

ηηηηb

“On elephant-trunk structures in the region ofO associations”

…and in astrophysical situationssuch as expanding nebula

A similar situation occursin ICF implosions

v

Frieman, Ap. J. 120, 18 (1954)

Initial conditionηηηη = ηηηηo cos(kx)

Initial conditionηηηη = ηηηηoe(kg)1/2 t

Nonlinear regimeηηηη = 0000....3333((((gλλλλ))))1/2t


Observations from SN1987A suggest strongmixing of the radioactive core into the envelope


Initial experiments relevant to the hydrodynamicsof core collapse supernovas were done on Nova


More “Star-like” instability experiments have beendeveloped on the Omega laser

Three-layer experiment

Cylindrical experiment

Spherical Experiment

More “star-like”

3-layers

Divergent geometry

— Cylindrical

— Spherical


Image of Tyco SNR by ChandraX-ray Satellite(2001)

Laser Produced Blast Wave in Xe Gas(Courtesy B. Ripin, NRL, 1991)

Astrophysical and Laboratory turbulent blast wavesshow many similar features


An example Cepheid variable is seen in M100


Cepheid variables are the most accurate distanceindicators, and establish Ho in the nearby universe

• Opacities are an essential ingredient to understanding Cepheid variables


Cepheid variables are stars whose intrinsicbrightness varies periodically with time


Cepheid variables are stars whose intrinsicbrightness varies periodically with time

Each Bump causes a dκ/dTwhich can lead to pulsation

The “beat Cepheids” are verysensitive to the opacity of FE

P1/P0

P0 (days)1 3 5 7

0.70

0.74

The “opacity problem” wassolved through expeirments onthe Nova and Luli lasers

nif and indirect drive inertial fusion target physics and...

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