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LLNL-PRES-7181781
High-Energy-DensityScienceattheNationalIgnitionFacility(NIF)
Warren HsingHigh Energy Density Science & Technology Leader, LLNLPresentation to: MIT UROPJan 13, 2016LLNL-PRES-718178
LLNL-PRES-XXXXXX This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. Lawrence Livermore National Security, LLC
Status and Plans for Indirect Drive on NIF
FY15 Ignition Strategic Review
May 18th 2015, Washington DC John Edwards ICF Program Director, LLNL
LLNL-PRES-7181782
§ National Ignition Facility
§ Inertial Confinement Fusion experiments on NIF
§ Discovery science experiments on NIF
§ Diagnostic capabilities
§ Summary
Outline
LLNL-PRES-7181783
The National Ignition Facility is the world’s most energetic laser
LLNL-PRES-7181784
LLNL-PRES-7181785
NIF concentrates 192 laser beams (~10 kJ each at 351 nm) into a few mm3 in a few nanoseconds
Mattertemperature >108 KRadiationtemperature >3.5 x 106 KDensities >102 g/cm3
Pressures >1011 atm
LLNL-PRES-7181786
We performed 416 shots in FY16 – shot rate has been increasing
§ Four major groups of users— ICF— HED Stewardship Science— Discovery Science— National Security Applications
§ Developing the capability for enhanced data rate experiments— 5 shots in 25 hours used to
characterize x-ray and proton sources
— 8 shots in 28 hours used to develop backlighter sources
— More experiments enable a faster rate of learning, more exploration, and more users on the facility
Targetshots byquarterandshotrate
LLNL-PRES-7181787
Over 50 active target diagnostics enable cutting edge science on the NIF
Year
Number of active target diagnostics
0
10
20
30
40
50
60
2009 2010 2011 2012 2013 2014
Nuclear Xray Optical
Cum
ulat
ive
Dia
gnos
tic C
ount
• LLNL • MIT• LANL • CEA• LLE • Duke
• NSTec • SNL• U of M • GSI• LBNL • AWE
LLNL-PRES-7181788
New diagnostics are needed to develop new insights and applications
~10-15 diagnostics are used on every target shot
n imageYield, Tion, mix, rho-r, bang time, …
VISAR
BackscatterFABS/NBI
EHXI, FFLEX
1D, 2D, spectroscopy, bang time
LLNL-PRES-7181789
NIF can reach a broad range of regimes for High Energy Density (HED) Science spanning ultra-dense-matter to high temperature plasmas
9We now have the ability to study relevant physics in those regimes
8
6
4
2
-5 50
Log
Tem
pera
ture
(K)
Log density(g/cm3)
Earth’s core
Jupiter
Log density (g*cm-3)
Log
tem
pera
ture
(K)
solid
HED regime P>1Mbar = .1 MJ/cc
Super Novaremnant
Inertial fusion
LLNL-PRES-71817810
Indirect Drive Inertial Confinement Fusion (ICF) uses a hohlraum to convert laser energy to X-rays
§ Hohlraum should provide — Spatial smoothing of the laser— Symmetric x-ray illumination of the capsule
which results in uniform ablation of capsule— Temporal shaping of the X-ray drive
resulting in an implosion with the required velocity and adiabat
Lawrence Livermore National Laboratory 5 Pxxxxxx.ppt – Edwards, FY15 Review, 5/18/15
XGray+drive+igni9on+requires+the+hohlraum+to+provide+a+symmetric+implosion+with+required+velocity+and+adiabat+
Laser "Pulse-shape"
Plastic Ablator
Gold hohlraum wall
Helium gas
Laser entrance hole (LEH)
~ 1cm
Lawrence Livermore National Laboratory 5 Pxxxxxx.ppt – Edwards, FY15 Review, 5/18/15
XGray+drive+igni9on+requires+the+hohlraum+to+provide+a+symmetric+implosion+with+required+velocity+and+adiabat+
Laser "Pulse-shape"
Plastic Ablator
Gold hohlraum wall
Helium gas
Laser entrance hole (LEH)
~ 1cm
Laser Pulse Shape
~ 1
cm
Plastic, Diamond or Be
LLNL-PRES-71817811
The capsule compresses DT fuel and creates a hot core
R.Betti,etal.,PhysicsofPlasmas17,058102(2010).
DT Shell
𝟏𝟐 𝑴𝑽
𝟐e~𝟐𝝅𝑹𝟑𝑷
V – peak shell velocity
DT gas
Energy balance: Hotspot internalenergy at stagnationShell kinetic
energy
Hot spot
DT Shell
Hotspot
Hotspot coupling
LLNL-PRES-71817812
Ignition requires: high V,
high compression rR, and high HS coupling 𝜺
Hot spot𝜏~ 𝑅 ��⁄
�~
𝜌𝑅𝑃 𝑅
�
𝑀�� = 4𝜋𝑅7𝑃
R.Betti,etal.,PhysicsofPlasmas17,058102(2010).
Newton’s Law:
𝑀 ≈ 𝜌𝑟4𝜋𝑅7For a thin shell:
DT Shell
Hotspot
Combining together gives𝑷𝝉~𝜺𝟏/𝟐×𝝆𝑹×𝑽
𝟏𝟐 𝑴𝑽
𝟐𝜺~𝟐𝝅𝑹𝟑𝑷From earlier:
r
R𝜌𝑟~𝜌𝑅For a massive shell:
The hotspot is inertially confined by the assembled shell rR
LLNL-PRES-71817813
§ Quantities have alpha-heating off as a measure of implosion quality
Lawson criteria measures progress toward ignition Current status cno-a =Pt/PtIGN ~ 0.65
ignition
t
a
a
LLNL-PRES-71817814
§ Quantities have alpha-heating off as a measure of implosion quality
§ Implosions are grouped into high convergence ~ 45 and lower convergence < 35
§ Lower convergence implosions have performed better – better hydrodynamic stability
§ Experiments have since confirmed that these lower convergence implosions are more stable at the ablation front
Lawson criteria measures progress toward ignition Current status cno-a =Pt/PtIGN ~ 0.65
ignition
t
a
a
Higher convergenceMore unstable
Lower convergenceMore stable
LLNL-PRES-71817815
We can plot an equivalent Lawson criteria in terms of measurable quantities for ICF: Yield X rho-r
§ Highest yield shots to date have significant alpha heating contribution ~ no-alpha yield
§ Diamond (HDC) ablators are .85x scale
cno-a
r
LLNL-PRES-71817816
The first published measurements of high-rR came from the Magnetic Recoil Spectrometer, an MIT led diagnostic
Assembly of High-Areal-Density Deuterium-Tritium Fuelfrom Indirectly Driven Cryogenic Implosions
A. J. Mackinnon,1 J. L. Kline,3 S. N. Dixit,1 S. H. Glenzer,1 M. J. Edwards,1 D. A. Callahan,1 N. B. Meezan,1 S.W. Haan,1
J. D. Kilkenny,5 T. Doppner,1 D. R. Farley,1 J. D. Moody,1 J. E. Ralph,1 B. J. MacGowan,1 O. L. Landen,1 H. F. Robey,1
T. R. Boehly,2 P.M. Celliers,1 J. H. Eggert,1 K. Krauter,1 G. Frieders,1 G. F. Ross,1 D.G. Hicks,1 R. E. Olson,4 S. V. Weber,1
B. K. Spears,1 J. D. Salmonsen,1 P. Michel,1 L. Divol,1 B. Hammel,1 C.A. Thomas,1 D. S. Clark,1 O. S. Jones,1
P. T. Springer,1 C. J. Cerjan,1 G.W. Collins,1 V. Y. Glebov,2 J. P. Knauer,2 C. Sangster,2 C. Stoeckl,2 P. McKenty,2
J.M. McNaney,1 R. J. Leeper,4 C. L. Ruiz,4 G.W. Cooper,8 A.G. Nelson,8 G. G.A. Chandler,4 K.D. Hahn,4 M. J. Moran,1
M. B. Schneider,1 N. E. Palmer,1 R.M. Bionta,1 E. P. Hartouni,1 S. LePape,1 P. K. Patel,1 N. Izumi,1 R. Tommasini,1
E. J. Bond,1 J. A. Caggiano,1 R. Hatarik,1 G. P. Grim,3 F. E. Merrill,3 D.N. Fittinghoff,1 N. Guler,3 O. Drury,1
D. C. Wilson,3 H.W. Herrmann,3 W. Stoeffl,1 D. T. Casey,6 M.G. Johnson,6 J. A. Frenje,6 R. D. Petrasso,6 A. Zylestra,6
H. Rinderknecht,6 D.H. Kalantar,1 J.M. Dzenitis,1 P. Di Nicola,1 D. C. Eder,1 W.H. Courdin,1 G. Gururangan,1
S. C. Burkhart,1 S. Friedrich,1 D. L. Blueuel,1 l. A. Bernstein,1 M. J. Eckart,1 D. H. Munro,1 S. P. Hatchett,1
A. G. Macphee,1 D. H. Edgell,2 D.K. Bradley,1 P.M. Bell,1 S.M. Glenn,1 N. Simanovskaia,1 M.A. Barrios,1 R. Benedetti,1
G.A. Kyrala,3 R. P. J. Town,1 E. L. Dewald,1 J. L. Milovich,1 K. Widmann,1 A. S. Moore,7 G. LaCaille,1 S. P. Regan,2
L. J. Suter,1 B. Felker,1 R. C. Ashabranner,1 M. C. Jackson,1 R. Prasad,1 M. J. Richardson,1 T. R. Kohut,1 P. S. Datte,1
G.W. Krauter,1 J. J. Klingman,1 R. F. Burr,1 T. A. Land,1 M.R. Hermann,1 D.A. Latray,1 R. L. Saunders,1 S. Weaver,1
S. J. Cohen,1 L. Berzins,1 S. G. Brass,1 E. S. Palma,1 R. R. Lowe-Webb,1 G.N. McHalle,1 P. A. Arnold,1 L. J. Lagin,1
C. D. Marshall,1 G.K. Brunton,1 D.G. Mathisen,1 R. D. Wood,1 J. R. Cox,1 R. B. Ehrlich,1 K.M. Knittel,1 M.W. Bowers,1
R. A. Zacharias,1 B. K. Young,1 J. P. Holder,1 J. R. Kimbrough,1 T. Ma,1 K.N. La Fortune,1 C. C. Widmayer,1 M. J. Shaw,1
G.V. Erbert,1 K. S. Jancaitis,1 J.M. DiNicola,1 C. Orth,1 G. Heestand,1 R. Kirkwood,1 C. Haynam,1 P. J. Wegner,1
P. K. Whitman,1 A. Hamza,1 E. G. Dzenitis,1 R. J. Wallace,1 S. D. Bhandarkar,1 T.G. Parham,1 R. Dylla-Spears,1
E. R. Mapoles,1 B. J. Kozioziemski,1 J. D. Sater,1 C. F. Walters,1 B. J. Haid,1 J. Fair,1 A. Nikroo,5 E. Giraldez,5 K. Moreno,5
B. Vanwonterghem,1 R. L. Kauffman,1 S. Batha,3 D.W. Larson,1 R. J. Fortner,1 D.H. Schneider,1 J. D. Lindl,1
R.W. Patterson,1 L. J. Atherton,1 and E. I. Moses1
1Lawrence Livermore National Laboratory, Livermore, California 94551, USA2Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
3Los Alamos National Laboratory, Los Alamos, New Mexico, 87545, USA4Sandia National Laboratory, New Mexico 87123, USA
5General Atomics, General Atomics, San Diego, California 92186, USA6Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
7AWE, Aldermaston, Reading, Berkshire, RG7 4PR, United Kingdom8Chemical and Nuclear Engineering Department, University of New Mexico, Albuquerque, New Mexico 87131
(Received 18 December 2011; published 24 May 2012)
The National Ignition Facility has been used to compress deuterium-tritium to an average areal density
of !1:0" 0:1 g cm#2, which is 67% of the ignition requirement. These conditions were obtained using
192 laser beams with total energy of 1–1.6 MJ and peak power up to 420 TW to create a hohlraum drive
with a shaped power profile, peaking at a soft x-ray radiation temperature of 275–300 eV. This pulse
delivered a series of shocks that compressed a capsule containing cryogenic deuterium-tritium to a radius
of 25–35 !m. Neutron images of the implosion were used to estimate a fuel density of 500–800 g cm#3.
DOI: 10.1103/PhysRevLett.108.215005 PACS numbers: 52.57.#z, 52.38.#r, 52.50.#b
In indirect-drive inertial confinement fusion, laser en-ergy is converted to thermal x rays inside a high-Z cavity(hohlraum) [1]. These x rays then ablate the outer layers ofa cryogenically layered deuterium-tritium (DT) filledlow-Z capsule placed at the center of the hohlraum, caus-ing the capsule to implode, compressing and heating thedeuterium and tritium ions. To achieve fusion ignition, theplasma density and temperature must be maintained toinitiate a self propagating burn wave before disassembly
or cooling reduces the fusion reaction rate and hence fusionpower gain below the power losses of radiation and thermalconduction. To efficiently burn a significant fraction of theDT fuel, areal densities ("R) larger than 1 g cm#2 arerequired [1,2]. Previously the highest "R (0:295"0:044 g cm#2) was measured in direct drive experimentson the Omega laser at the University of Rochester [3].These experiments used a laser pulse shape that was tunedto produce a low adiabat implosion (where the in-flight (IF)
PRL 108, 215005 (2012) P HY S I CA L R EV I EW LE T T E R Sweek ending25 MAY 2012
0031-9007=12=108(21)=215005(5) 215005-1 ! 2012 American Physical Society
CR-39
Target CH-foil or CD-foil
6-28 MeV (p)3-14 MeV (d)
ExitEntrance
Detector housing
LLNL-PRES-71817817
Ignition on NIF requires convergence ~ 35 to reach ~350 Gbars and 1000 gm/cc
~ .1 mm
~1000 gm/ccDense DT shell
Hot spot
100 gm/cc5 keV
rR ~ 1.5 g/cm2
P ~ 350 GB
Eignition ~ ρR3T ~ρR( )3 T 3
Pstag2
But experiments are like this
If nature were 1 D
NIS!
Polar emission!
D T
na
LLNL-PRES-71817818
Currently the conditions are ~ 2x from what is needed
~500 gm/cc
~40 gm/cc~ 5 keV
~.75 gm/cc~ 200 GB
Best performance on a single shot
~ .1 mm
~1000 gm/ccCold DT shell
Hot spot
100 gm/cc5 keV
a redepositsenergy
rR ~ 1.5 g/ccP ~ 350 GB
LLNL-PRES-71817819
Two major factors currently believed to be limiting performance are hydro instabilities and drive symmetry
Oncetheseissuesareaddressed,theremaybeothersthatmayhavetobesolved
Lawrence Livermore National Laboratory 17 Pxxxxxx.ppt – Edwards, FY15 Review, 5/18/15
Two+major+factors+(and+surprises)+are+believed+to+be+limi9ng+current+performance+(also+prominent+in+NIC)+Poor%control%of%9me+dependent+%
drive%symmetry%from%the%hohlraum%(PRD:%drive%target%coupling)%
These%are%the%focus%of%the%immediate%go%forward%program%Once%resolved,%other%factors%may%have%to%be%overcome%%to%achieve%igni2on%such%as%prehea2ng%by%hot%electrons%
Hydrodynamic%instability%seeded%by%the%capsule+support+
(PRD:%Implosion)%
~%50%µm%~%500%µm%
~%5000%µm%Post%NIC%experiments%were%designed%to%reduce%instability+
Lawrence Livermore National Laboratory 17 Pxxxxxx.ppt – Edwards, FY15 Review, 5/18/15
Two+major+factors+(and+surprises)+are+believed+to+be+limi9ng+current+performance+(also+prominent+in+NIC)+Poor%control%of%9me+dependent+%
drive%symmetry%from%the%hohlraum%(PRD:%drive%target%coupling)%
These%are%the%focus%of%the%immediate%go%forward%program%Once%resolved,%other%factors%may%have%to%be%overcome%%to%achieve%igni2on%such%as%prehea2ng%by%hot%electrons%
Hydrodynamic%instability%seeded%by%the%capsule+support+
(PRD:%Implosion)%
~%50%µm%~%500%µm%
~%5000%µm%Post%NIC%experiments%were%designed%to%reduce%instability+
Poor time-dependent control of x-ray flux symmetry from the hohlraum
Hydrodynamic instabilities seeded by capsule features: support & fill tube
LLNL-PRES-71817820
Hydrodynamic instabilities can cause mix and prevent efficient stagnation
Lawrence Livermore National Laboratory 40 Pxxxxxx.ppt – Edwards, FY15 Review, 5/18/15
Hydro+instability+can+disrupt+the+capsule,+cause+mix+and+prevent+efficient+stagna9on++
XSrays%preheat%ablator%
Tent%Fill%tube%Surface%roughness%
Surface%roughness%
Bulk%inhomogeneity%
Pulse%shape%Dopant%(less%beeer)%Ablator%
Dopant%(more%beeer)%Drive%spectrum%
Seed% Control%
Focused%experiments%are%needed%to%validate%models%and%guide%mi2ga2ons%Focusedexperimentsneededtoguidemitigationsandimprovemodels
Alternate tent and fill tube supports
LLNL-PRES-71817821
Techniques and diagnostics are being developed to measure in all phases of the implosion
Lawrence Livermore National Laboratory 41 Pxxxxxx.ppt – Edwards, FY15 Review, 5/18/15
500 um
300 um
750 um
900 um
Techniques+now+exist+to+measure+instability+in+all+important+phases+of+the+implosion+–+improvements+planned+
This%will%allow%us%to%validate%our%understanding%and%modeling%and%guide%mi2ga2ons%
• Abla2on%front%%–%accelera2on%phase%HGR%
• AblatorSice%interface%%–%accelera2on%phase%layered%HGR%
• Decelera2on%growth%by%self%backligh2ng%
• %%%%%Measure%mix%at%peak%compression%%%%%%%%%%%–%Meteor%imaging,%spectroscopy%%%%%%%%%%%–%CD%layers%HYDRA simulations
110%nm%%tent%
45%nm%%tent%
LLNL-PRES-71817822
In-flight x-ray radiography measurements of rippled spherical capsules allows experimental Rayleigh-Taylor growth factors to be compared with simulations
RippledLower convergencedesign
z(cm)
R(c
m)
Higher convergencedesign
Simulations - density plots
Growthfactorvs modenumber
LLNL-PRES-71817823
Imaging a single limb of the capsule in the Hydro-Growth Radiography (HGR) target quantifies the rR perturbation
600 µm
0.0
-0.4
0.4
OD
-0.2
0.2
45-nm tent
110-nm tent
divots
laser
backlighter
30 µm FT @ 65 Hz
tent
Removing the tent is still a work in progressSeveral options being pursued and tested
H. Robey, V. Smalyuk
Minimal wire support
wires perpto page
wires parallelto page
Supported fill tube
LLNL-PRES-71817824
Implosions using diamond ablators showed a prominent jet of material at the location of fill tube greater than predicted
Lawrence Livermore National Laboratory 17 Pxxxxxx.ppt – Edwards, FY15 Review, 5/18/15
Two+major+factors+(and+surprises)+are+believed+to+be+limi9ng+current+performance+(also+prominent+in+NIC)+Poor%control%of%9me+dependent+%
drive%symmetry%from%the%hohlraum%(PRD:%drive%target%coupling)%
These%are%the%focus%of%the%immediate%go%forward%program%Once%resolved,%other%factors%may%have%to%be%overcome%%to%achieve%igni2on%such%as%prehea2ng%by%hot%electrons%
Hydrodynamic%instability%seeded%by%the%capsule+support+
(PRD:%Implosion)%
~%50%µm%~%500%µm%
~%5000%µm%Post%NIC%experiments%were%designed%to%reduce%instability+
LLNL-PRES-71817825
Radiographic measurements of the fill tube perturbation revealed an issue not captured in 2D simulations
laser
backlighter
tent Fill tube
Rho-r variations ~ in magnitude to fill tube
LLNL-PRES-71817826
Imaging the fill tube perturbation revealed an issue not captured in 2D simulations
laser
backlighter
tent Fill tube
Rho-r variations ~ in magnitude to fill tube
We are developing mitigations – smaller 5µ fill tubes, prepulse expansion
Beam spotscreateX-ray shadows
Q31T
Q26B
Q36TQ26T A. MacPhee
LLNL-PRES-71817827
Two major factors currently believed to be limiting performance are hydro instabilities and drive symmetry
Oncetheseissuesareaddressed,theremaybeothersthatmayhavetobesolved
Lawrence Livermore National Laboratory 17 Pxxxxxx.ppt – Edwards, FY15 Review, 5/18/15
Two+major+factors+(and+surprises)+are+believed+to+be+limi9ng+current+performance+(also+prominent+in+NIC)+Poor%control%of%9me+dependent+%
drive%symmetry%from%the%hohlraum%(PRD:%drive%target%coupling)%
These%are%the%focus%of%the%immediate%go%forward%program%Once%resolved,%other%factors%may%have%to%be%overcome%%to%achieve%igni2on%such%as%prehea2ng%by%hot%electrons%
Hydrodynamic%instability%seeded%by%the%capsule+support+
(PRD:%Implosion)%
~%50%µm%~%500%µm%
~%5000%µm%Post%NIC%experiments%were%designed%to%reduce%instability+
Lawrence Livermore National Laboratory 17 Pxxxxxx.ppt – Edwards, FY15 Review, 5/18/15
Two+major+factors+(and+surprises)+are+believed+to+be+limi9ng+current+performance+(also+prominent+in+NIC)+Poor%control%of%9me+dependent+%
drive%symmetry%from%the%hohlraum%(PRD:%drive%target%coupling)%
These%are%the%focus%of%the%immediate%go%forward%program%Once%resolved,%other%factors%may%have%to%be%overcome%%to%achieve%igni2on%such%as%prehea2ng%by%hot%electrons%
Hydrodynamic%instability%seeded%by%the%capsule+support+
(PRD:%Implosion)%
~%50%µm%~%500%µm%
~%5000%µm%Post%NIC%experiments%were%designed%to%reduce%instability+
Poor time-dependent control of x-ray flux symmetry from the hohlraum
Hydrodynamic instabilities seeded by capsule features: support & fill tube
LLNL-PRES-71817828
Gas-filled hohlraums are complex environments
Hot electron preheat
X-rays, M-band
Inverse Bremsstrahlung Absorption(collisional absorption)
Parametric instabilities cause- Scattered light (200kJ backscattered)- Hot electrons (preheat fuel)
Cross beam energy transfer is needed to transfer energy to inner beams in high gas fill hohlraums
Thermal Conduction to walls
Walls expand inward and radiate X-raysCapsules ablate and plasma expands outwards
Lowergasfillswherelaserplasmainstabilitiesarelowistheapproachnowbeingtaken–challengeisplasmafilling
LLNL-PRES-71817829
Adding a little gas helps: looks promising for longer pulses needed for CH and Be, and appear to further reduce symmetry swings
LLNL-PRES-681338 24
Less need for ad-hoc drive multipliers in order to match measured bang-time
Gas-fill study
P0 = 158 μm P2 = -10 μm
P0 = 63 μm P2/P0 = -19%
In flight
300 µm
100 µm
Stagnation
Best operating range?
Shape
P0 = 156 μm P2 = -7.5 μm
P0 = 67 μm P2/P0 = -35%
Exp
t. S
im.
Adding a little gas helps: looks promising for longer pulses needed for CH and Be, and appear to further reduce symmetry swings
LLNL-PRES-681338 24
Less need for ad-hoc drive multipliers in order to match measured bang-time
Gas-fill study
P0 = 158 μm P2 = -10 μm
P0 = 63 μm P2/P0 = -19%
In flight
300 µm
100 µm
Stagnation
Best operating range?
Shape
P0 = 156 μm P2 = -7.5 μm
P0 = 67 μm P2/P0 = -35%
Exp
t. S
im.
Adding a little gas helps: looks promising for longer pulses needed for CH and Be, and appear to further reduce symmetry swings
LLNL-PRES-71817830
Focused experiments are underway to measure the temperature and wall motion in gas fill hohlraums
Allowsustocompareingreaterdetailwheremodelsdeviate
Innerbeam
Outerbeam
Gold bubble expansion and spot motion
Bubble-capsuleinteraction
Ne,Te,flowinbeampath&energydeposition
Ne,Te,Z*goldbubblehighlyresolvedspectra Mn:Co thermometer
LLNL-PRES-71817831
Ways to mitigate wall motion are being developed
Allowsustoimprovesymmetryoruselargercapsulesandcouplemoreenergy
Innerbeam
Outerbeam
Low density foam
20 mg/cc Ta2O5 delays filling by ~1 ns
LLNL-PRES-71817832
On approach to reduce to the impact of asymmetrical drive is to reduce the convergence of the implosion
0 10 20 30 40 501
10
100
Convergence ratio
1D Y
OC
[bur
n−of
f]
Low footHigh footHDC2−shockIDEP
0 10 20 30 40 501
10
100
Convergence ratio
1D Y
OC
[bur
n−on
]
Low footHigh footHDC2−shockIDEP
YOCvs.Convergenceratio
Limitedbyachievablevelocity(andavailable
energy)
Increasingsensitivityto3Derrors
Ignitionspace
Ignitionspace
LLNL-PRES-71817833
Recent experiments have demonstrated the ability to get symmetrical implosions with convergence ~ 25
Lawrence Livermore National Laboratory 37 Pxxxxxx.ppt – Edwards, FY15 Review, 5/18/15
A+li\le+gas+may+help+symmetry+control++–+without+compromising+on+LPI,+hot+electrons;+more+to+do+
P2 = 4 um P2 = 5 um P2 ~ 2 µm
P0 = 55 um
800 µm
800 µm
Implosion of 80µm undoped diamond shell 6.72mm, 0.6 mg/cc He
370 TW, 1.1 MJ, 5.5 ns pulse (33% cone fraction)
Oggie Jones
P0 = 55 um
300 µm
Key%results%%• Coupling%remains%high,%very%low%LPI%/%hot%electrons%%• Symmetric%implosion,%predicted+by+code++
(a~3,%CR~20,%v%~%230%km/s)%
• Predicted%drive%spectrum%slightly%too%hard%
§ Key results
§ • Coupling remains high, very low LPI / hot electrons with intermediate gas fill (.6mg/cc He)
§ • Symmetric implosion, predicted by code (a~3, CR~20, v ~ 230 km/s)
§ • Predicted drive spectrum slightly too hard
Wearealsoexploringlowerconvergence,higheradiabat implosions
LLNL-PRES-71817834
§ Develop a near 1D implosion close to ignition space that is understood and predictable— Identify through measurements, issues and develop mitigations
§ Slopes around that space that is understood and predictable
§ Understand the key physics necessary for ID ignition
Goals for IDI over the next 5 years
LLNL-PRES-71817835
NIF can reach a broad range of regimes for High Energy Density (HED) Science spanning ultra-dense-matter to high temperature plasmas
35We now have the ability to study relevant physics in those regimes
8
6
4
2
-5 50
Log
Tem
pera
ture
(K)
Log density(g/cm3)
Earth’s core
Jupiter
Log density (g*cm-3)
Log
tem
pera
ture
(K)
solid
HED regime P>1Mbar = .1 MJ/cc
Super Novaremnant Shock heating
LLNL-PRES-71817836
Weareabletoreach~Gbar shockpressureswhereionizationeffectstheequationofstate
Density (g/cm3)3 4 5
Pres
sure
(Gba
r)
10
1.0
0.1
0.01
.001
Quantum model
ThomasFermi
Nova data
Omega data
Osaka data
CH
X-ray Radiography
backlighter
Thomson scattering
sample
Neutron time of flight
Gigabar Equation of State experiment
Kraus, Swift, Doeppner, Kritcher, Falcone, et al.
University collaboration with NIF
Convergent single shock radiography
us
up
LLNL-PRES-71817837
NIF can reach a broad range of regimes for High Energy Density (HED) Science spanning ultra-dense-matter to high temperature plasmas
37We now have the ability to study relevant physics in those regimes
8
6
4
2
-5 50
Log
Tem
pera
ture
(K)
Log density(g/cm3)
Earth’s core
Jupiter
Log density (g*cm-3)
Log
tem
pera
ture
(K)
solid
HED regime P>1Mbar = .1 MJ/cc
Super Novaremnant
Ramp Compression
LLNL-PRES-71817838
[RayF.Smith etal.,Nature511,330(2014)]
The EOS of diamond (carbon) was measured by ramp compression up to 50 Mbar at NIF
Ramp compression conditions created by laser pulse shaping
Velocity of several thicknesses + Lagrangian analysis -> sx-V
Time (ns)
Free
sur
face
vel
ocity
(Km
/s)
15 18 21
25
50
0
50
40
30
20
10
0
Fre
e-S
urf
ac
e V
elo
cit
y (
km
/s)
21201918171615Time (ns)
140 µm Diamond 151 µm Diamond 162 µm Diamond
5
4
3
2
1
0
Stre
ss (
TPa)
1210864Density (g/cc)
Isent
rope
Hugo
niot
Stre
ss (M
bar)
50
25
0 Previous solid state data
Data show a significantly stiffer response compared to the isentrope
Ramp data
LLNL-PRES-71817839
The crystal structure of ramp-compressed carbon up to peak pressures of ~15 Mbar on NIF has been measured
Carbon
2q (deg) 30 50 70 90Si
gnal
str
engt
h (a
u)
Exprmnt
FC8 BC8 SC1
0 10 20 30 40Pressure (Mbar)
Tem
pera
ture Carbon phases
0
4000
8000
[Courtesy of Amy Jenei; and Jon Eggert]
Built on work originally pioneered on a laser by J. Wark
VISAR: Determines pressure
Diffraction
X-ray Source Laser
TargetAssembly
Foil
LLNL-PRES-71817840
NIF can reach a broad range of regimes for High Energy Density (HED) Science spanning ultra-dense-matter to high temperature plasmas
40We now have the ability to study relevant physics in those regimes
8
6
4
2
-5 50
Log
Tem
pera
ture
(K)
Log density(g/cm3)
Earth’s core
Jupiter
Log density (g*cm-3)
Log
tem
pera
ture
(K)
solid
HED regime P>1Mbar = .1 MJ/cc
Super Novaremnant
Collisionless plasmas
LLNL-PRES-71817841
The NIF astrophysical collisionless shock experiment is seeing the beginning stages of shock formation
Laser hitting the target
X-ray brightening from self-emission of hot plasmas
Foil 1
Foil 2
Self-generated protons imaged with a pinhole onto CR39
[Courtesy of Hye-Sook Park, Youichi Sakawa and Steve Ross]
PIC simul. of Weibel interactions
[Huntington, Nature Phys. (2015)
Omega exprmnt
(Self generated) X-ray imaging
Self-generated proton imaging
LLNL-PRES-71817842
AstrophysicalCollisionless Shockeffortisaworldwidecollaboration
LLNL (USA)H.-S. Park, D. Casey, F. Fiuza,C. Huntington, C. Plechaty,B. Remington, S. Ross D. Ryutov
Osaka University (Japan)Y. Sakawa, H. Takabe,Y. Kuramitsu, T. Morita,Y. Yamaura, T. Ishikawa
University of Chicago (USA)D. Lamb, A. Scopatz, P. Tzeferacos
Rice University (USA)E. Liang, M. Levy
LULI (France)M. Koenig, A. Ravasio
York University (UK)N. Woolsey
University of Michigan (USA)R. P. Drake, C. Kuranz, W. Wan
MIT (USA)R. Petrasso, C. Li, A. Zylstra
Oxford University (UK)G. Gregori, J. Meineke
Princeton University (USA)A. Spitkovsky, D. Caprioli
LLE, Univ. of Rochester (USA)D. Froula, G. Fiskel, P.-Y. Chang
LLNL-PRES-71817843
Collisionlessastrophysical shocks
Magnetogenesis and B field amplification
Direct-drivehydrodynamics
Stellar and Big Bang nucleosynthesis
Charged particle stopping powers
Self-similar instabilities
Iron melt curve,magnetospheres, and habitable Super Earths
Metastabilityof dynamically compressed C
Pressure ionization at extreme densities
Proton radiograph
X-rayradiograph
B-field & optical image of M51
Wark (Oxford) Hemley (Carnegie) Neumayer (GSI) Casner (CEA) Shvarts (Israel)
Zylstra (MIT) Gatu-Johnson (MIT) Gregori (Oxford) Sakawa (Osaka)
Nine new NIF Discovery Science experiments have started in FY16
LLNL-PRES-71817844
New class of petawatt lasers have potential for accessing and probing high energy density conditions
§ High intensity electric and magnetic fields are generated
€
εE2
2= 1 Mbar E ~ 1011 W/cm2 ~ e/r2
electric field in Bohr atom
Hot electrons, protons, Ka, MeV bremstrahlung are generated
€
quiver momentummec
= 1I ~ 1018 W/cm2
I ~ 3 x1015 W/cm2 Hot electrons ------> Ka X-rays
electrons
protons
bremstrahlung
Kalaser
I ~ 1019 W/cm2 Mev Bremstrahlung
I ~ 1020 W/cm2 Mev protons, 400 MG, pair production
LLNL-PRES-71817845
CompressedFF(2.3kJ)
A B
The Advanced Radiographic Capability (ARC) has been commissioned and the first experiments are being performed
ARC beampathDiagnostic beampath
Compressor vessel #1
Parabola vessel
Currently 750 J per beamlet routineWorking towards 1.5kJ per beamlet
High energy x-ray images (eHXI)
Ave. E ~50 keV ~90 keV ~105 keV
LLNL-PRES-71817846
Compton scatteringX-ray radiography with ARC allows imaging of dense, high-z targets
The first use of ARC will be to provide X-ray sources for radiography
ARC
56 keV
Gated X-ray Detector
Material strength data
Ag
ARC22 keV
Complex Hydro dataARC
20µm Au wire
Imploded core scattering
75-200 keV
AXIS
Data from a double shocked HDC sphere
LLNL-PRES-71817847
RadiationTransport,Opacity,&Effects
X-raySourceFormationMulti-layerWolterLocalizedTe/neOpticalTS
ComplexHydrodynamics
Meso-scaleHydroInstabilitiesMulti-layerWolterMixFractionTime-Resolvedg Spect
HighPressureMaterials
IgnitionApplicationsandBurn
Time-resolvedBurn-vs.EnergyTime-Resolvedn/g Spect.–MRS(t)-vs.Space3-Dn/g Imaging-EquilibrationHigh-ResX-raySpect.
DT gas
IceDTgas
Exploding Pusher
IgnitionCapsule
PhaseandstructureTime-dependentX-raydiffractionStrengthMulti-layerWolter
We are investing in “Transformational” diagnostics that are at the resonance between the most compelling needs and the most promising technologies
LLNL-PRES-71817848
48
48
There is a multi-national effort in developing the next generation diagnostics on HED facilities
A new generation of diagnostics is needed to fully exploit our three marvelous HED facilities
LLNL-PRES-71817849
This is a great time for HED science: experimental facilities, diagnostics, computational capabilities and challenging scientific questions to answer
49We VERY MUCH value the partnership we have with MIT on HED science
8
6
4
2
-5 50
Log
Tem
pera
ture
(K)
Log density(g/cm3)
Earth’s core
Jupiter
Log density (g*cm-3)
Log
tem
pera
ture
(K)
solid
HED regime P>1Mbar = .1 MJ/cc
Super Novaremnant
This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344
High Energy Density Summer Scholar Program2017
Seeking students with interest the plasma, hydrodynamic, nuclear and spectroscopic physics associated with the study of matter under extreme conditions
More information can be found: http://students.llnl.govUndergraduate and Graduate students can apply to Job ID 101685:http://careers-ext.llnl.govContact Art Pak (pak5@llnl.gov) for more information
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