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Gilbert CollinsIFSA University Use of NIFLLNL-PRES-416675
This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344
University Use of NIF Science
MBar compression P∆V ~ eV, Bonds change
GBar compression P∆V ~ KeV, Atoms change
dynamic compression
2
NIF generates pressures found at the center of Jupiter
NIF will create ≥1033 neutrons per cm2 per second, equivalent to a supernova
NIF will access unprecedented energy densities
NIF will produce enough x-ray flux to simulate conditions in an accretion disk
NIF will create thermal plasmas at the conditions of stellar interiors
Hydrogen Phase space for high energy density science
4
Log
Tem
pera
ture
(K)
Log density (g•cm-3)
Hydrogen Phase space for high energy density science
5
Log
Tem
pera
ture
(K)
Log density (g•cm-3)
Hydrogen Phase space for high energy density science
6
Log
Tem
pera
ture
(K)
Log density (g•cm-3)
Hydrogen Phase space for high energy density science
7
Hot spot108 K
Cold fuel1 Kg/cc
Log
Tem
pera
ture
(K)
Log density (g•cm-3)
Hydrogen Phase space for high energy density science
8
Log
Tem
pera
ture
(K)
Log density (g•cm-3)
Previous experiments
Hydrogen Phase space for high energy density science
9
High energy density regime to explore with NIF
With Burning plasmasLo
g Te
mpe
ratu
re (K
)
Log density (g•cm-3)
Time (ns)
Tota
l pow
er (T
W)
150
0 10 20
75
0
With precompressedD-> ~5 g/cc
Pulse shape ultra-high pressure plasma and solid-state experiments
Stixrude, 2008
4
2
104
8
4
2
103
8
40.1 1 10 100 1000
Pressure (Mbar)
Tem
pera
ture
(K)
NIF can produce P > 1 Gbar shocks, P> 10’s Mbar for Ramp compression
Fluid
Iron
Ramp
NIF’s Pulseshaping and Burn will enable extreme solid state to fusion experiments
10
Shock
Ramp
Time (ns)
Tota
l pow
er (T
W)
150
0 10 20
75
0
With precompressedD-> ~5 g/cc
Pulse shape ultra-high pressure plasma and solid-state experiments
Stixrude, 2008
4
2
104
8
4
2
103
8
40.1 1 10 100 1000
Pressure (Mbar)
Tem
pera
ture
(K)
NIF can produce P > 1 Gbar shocks, P> 10’s Mbar for Ramp compression
Fluid
Iron
Ramp
NIF’s Pulseshaping and Burn will enable extreme solid state to fusion experiments
11
Shock
Ramp
NIF’s high energy and pulseshaping will enable extreme solid state to fusion experiments
12
Time (ns)
Tota
l pow
er (T
W)
60
0 10 20
30
0
With precompressedD-> ~5 g/cc
Pulse shape for ignition
Ignition, 1019
neutronsTr ~ 5 KeV
VanHorn
We are just now trying to determine regimes accessible with ignition, this example is again for Fe
With ignition, the regimes we will be able to access are still more extreme
Hugoniot
We are just starting to develop science “platforms” to explore this new frontier of science
14
R. Jeanloz, T. Duffy, R. Hemley, Y. Gupta, P. Loubeyre, L. Stixrude, S. Rose, J. Wark, G. Collins
S. Rose, R. Betti, J. Meyer-Ter-Vehn, S. Atzeni, G. Collins
P. Drake, D. Arnett, A. Frank, T. Plewa, T. Ditmire, A. Takabe, B. Remington
Astro/Rad-transport & Hydrodynamics
G. Fuller, U. Greife, Z. Shayer, C. Brune, R. Boyd, L. Bernstein
N. Fisch, C. Niemann, C. Joshi W. Mori, B. Afeyan, D. Montgomery, A. Schmitt, B. Kirkwood
Omega experiments can access the few Mbar regime, ~0.8 * RJupiter
NIF experiments can access the most extreme conditions in any planet
2 Mbar
5300 K
77 Mbar
16000 K
C. J. Hamilton
Some Key Issues:• What is a solid at >10 Mbars• How does H behave at 5,10,…g/cc
• What chemistry occurs at Mbar-Gbar conditions
NIF will be able to recreate the most extreme conditions of any planet
15
Russ Hemley Carnegie InstituteKev Chemistry
RaymondJeanloz U.C.Berkeley
Yogi GuptaWashington State Solids at
P>20Mbar
LLLNIF, DNT, PLS, Eng
D. StevensonCalTechPlanet Models
Lars Stixrude Univ. of MichiganExtreme Chemistry
BurkhardMilitzer Earth and
Planetary ScienceRichard Martin
U. IllinoisSolid State Theory
Justin WarkOxford University
Tom Duffy PrincetonElastic consts& rigidity
W. HubbardU. ArizonaPlanet theory
Paul Loubeyre CEA H & H/He atP>10 Mbar
Steven RoseImperial College,LondonPlasma Physics
Group
The team of leading scientists in the field of ultra-dense matter continues to grow
W. Mao (Stanford), K. Lee (Yale), R. Wentzcovitch, C. Bolme (LANL), T. Guillot, (Obs. Nice)
16
Many of the techniques have been benchmarked on the Omega, Jupiter, and Vulcan laser facilities
30 Mbar NIF design is scaled from 8 Mbar Omega experiments
Stre
ss (M
bar)
0
15
30
Density (g/cc)1062
Time (ns)
Tota
l pow
er (T
W) 100
50
0 0 10 20
We will discover if carbon stays solid and strong at 10’s of Mbar
Next year we will extend solid state physics to 30 Mbars on NIF
18
Eggert, Hicks
Eggert, Braun
Metallic polymeric fluid phase
Materials science/planetary interiors platform- ramp condition of Fe to super-earth conditions (~ 20 Mbar)
Target: ignition hohlraum, phase plates; specialized drive, package Diagnostics
VISAR/SOP (90,45)
TARPOS
TAS
OPAS/NOPAS
DANTEX-ray drive
VISAR/SOP(90,315)
Dia
mon
d Fe VISAR/SOP
In addition to being able make solids at 10’s of Mbar, we can now study these solids with diffraction, EXAFS, velocimetry, and broad band reflectance
Time (ns)
Pow
er (T
W)
100
50
0 20 40
150
0
NIF laserpulse
Imaging 17.5 KeV image of shocks (Hicks, Park, et al)
500 μm Qz
Omega
Shock
Diffraction for structure & strength=>Fe is HCP to 5 Mbar (Wark, Duffy, Gupta, Eggert, Harweliak, Rygg et al)
X-ray Scattering/absorption => local structure in Fe to 3 Mbar (Hemely, Hicks)
Advanced diagnostics are being developed to explore the microscopic physics in this dense matter regime
20
Optical spectroscopy to determine bonding (Bolme, Hemely, )
Hi-res interferometry for shock structure (Celliers, Smith, Brygoo)
Simultaneous diffraction and velocity measurements give compressibility and phase to 5 Mbar
21
Stre
ss (M
bar)
0
1.5
3.0
Time (ns)1050
Velocity (km/s)
10
1.85 Mbar
3.24 Mbar
Eggert, Rygg
This is by far the highest P diffraction ever collected and sets the stage for NIF experiments
Powder diffraction on ramp compressed samples
10 μm Fe
X-ray Scattering/absorption shows local structure in Fe to 3 Mbar (Hicks)
Yacoi, Remington
Data at P = 3 Mbar
We also developed EXAFS for Ultra-hi-P solidsDetermines Fe structure + coordination+T
Preliminary analysis suggestsHCP with c/a ~1.73
We expect the combination of Diff. + EXAFS will give T
χ
Electron wavenumber (A-1)Hicks,Ping
Yakoby, Remington et al
22
Loubeyre 06
The technique has been demonstrated on Omega to 200 GPa, and is expected to scale to 10+ TPa on NIF (Eggert PRL 08, Jeanloz PNAS 07, Lee JCP 06, Loubeyre JHP 06)
Coupling diamond cells to laser shocks enables access to ultra-high density states for He, H2, He+H2
23
10 kbar
50 kbar.6 Mbar
H2
Precompressed shocks
100
1000
10000
T(K
)
Conducting fluidJupiter
P+e
Metal HSolid H2
Fluid H2 ~isentrope
.01 0.1 1 10 100P(Mbar)
He
Visar
LaserDiamond cell
Loubeyre 06
The technique has been demonstrated on Omega to 200 GPa, and is expected to scale to 10+ TPa on NIF (Eggert PRL 08, Jeanloz PNAS 07, Lee JCP 06, Loubeyre JHP 06)
Coupling diamond cells to laser shocks enables access to ultra-high density states for He, H2, He+H2
24
10 kbar
50 kbar.6 Mbar
H2
Precompressed shocks
100
1000
10000
T(K
)
Conducting fluidJupiter
1st NIF H2 experiment
Metal HSolid H2
Fluid H2 ~isentrope
.01 0.1 1 10 100P(Mbar)
He
Visar
LaserDiamond cell
HED facilities deliver: E/V ≥ 1011 J/m3 or P ≥ 1 Mbar over spatial scales L ≥ 1 mm
Currnet ultra-dense matter plans for NIF include 10’s Mbar solids & 10’s of Gbar dense plasmas
FY12FY11FY10
New regime of Solid-state – 10 to 100’s of Mbar
Ultra-dense Hydrogen
Kilovolt chem/Gigabar press.
30 Mbar Carbon 6 shots
Fe-ramp to 20Mbar, 4 shots
Diffraction structure & T 4 shots
EXAFS for local order 4 shots
50 Mbar He/H2
4 shots
D2 to 6 g/cc4 shots
Shock Fe to 1 Gbar
4 shotsFe @ 10’s Gbar 4 shots
EXAFS/diffraction at >100 Mbar 4 shots
H @ many Gbar
H-D 100 Mbar (Pycnonuclear)
t
Convergent experimentsAtomic scale data & H in new regime
1-D compression Ignition hohlraumsVISAR/SOP
Burning Plasmas
• What physics limits optimizing burn?
• How does matter behave in DT burning environment, ie. Radiation and relativistic regimes?
• What are the next advanced ignition concepts?
26
NIF will open a new field of Burning Plasma physics, what are the key questions
• Understand/optimize the burning plasma
— e-ion equilibration
— Alpha deposition
— EOS/opacities and non-equilibrium
— Effects of extreme fields
— Plasma effects on nuclear reactions
• New burning plasma physics?
— Extreme neutron and photon flux
— e+e- pairs
— Photonuclear processes
27
Does a deep understanding of burning plasmas enable new ignition concepts?
Density-temperature at peak rho-R
Faster Ignition
300keV DT ions
Djaoui, JQSRT (1995), Rose
2000
1500
1000
500
00 20 40 60
10
30
50
70
Te , T
i (keV)⟩(gcm
-3)
Radius (µm)
⟩
Ti
Te
Previous Photoionised plasmas achieved ξ=20ergcms-1, NIF will achieve >1000ergcms-1
28
Low mass X-ray binaryξ=30 ergcms-1
Seyfert galaxyξ=300 ergcms-1
NIF with burning capsule
FFe
CH
Laboratory Astro/Nuclear Physics
29
• Measure opacities relevant to stellar evolution
- Can measure LTE and non-LTE conditions at high T and high or low rho
• Test codes modeling turbulence on NIF- Supernovea simulations suggest
significant mix: NIF can benchmark these simulations
- How were heavy elements dispersed in the Universe
• Test nuclear physics models- Benchmark excited state nuclear physics- Dense plasma effects on reaction rates- Test models for big bang nucleosynthesis- Helps to determine temperatures of stars
Saturn Z pinch 1990s
Z, ZR, Omega 2000-2009
NIF 2010-2015?
Kifonidis,Ap. J. Lett 531, L123 (2000)
5 x 1011cm
HFe
NIF will reach near core conditions of the sun and measure κRosseland to ~10%
Ti n=2 to n=1
Ti n=3 to n=1
Ti data at Omega.05 g/cc, 125 eV,
Solar Radiative Region: 200-1350 eV (Bahcall, Rev. Mod. Phys. 67, 781, 1995)
NIF 750 TW estimate from semi-emperical scaling: >700 eV(Dewald PRL 95, 215004(2005).)
Capsule Backlighter
collimator
Hohlraum
X-ray flash
Hohlraumtemperature
Sample volume with radiography
Gated x-ray spectrometer
Hohlraumtemperature
Supernovae come in two general categories
• Involve M~Msun stars• Optically brighter• Standardized candles• Serve as distance indicators
31
Type II: Core CollapseType 1A: Thermonuclear
Accreting white dwarf
H He
C,OSiFe
Mantle
Envelope
Core
• Involve M >> Msun stars• More energetic• More frequent• Leaves a neutron star behind
Fe core in massive star collapses
White dwarfCompanion star
Supernovae come in two general categories
• Source of the elements up to Z ~ 26• Data behind the accelerating universe
and dark energy
32
Type II: Core CollapseType 1A: Thermonuclear
Accreting white dwarf
H He
C,OSiFe
Mantle
Envelope
Core
• Source of the heavy elements, Z > 26• Questions:
− How are these elements made?− How are they ejected?
Fe core in massive star collapses
White dwarfCompanion star
Type II supernovae result from the death of a massive star
33
[Hillebrandt, Sci. Am., 43 (Oct. 2006)]
Near-death, the massive star, M > 8Msun , takes on an onion-layer structure
4 x 106 km
Type II supernovae result from the death of a massive star
34
[Hillebrandt, Sci. Am., 43 (Oct. 2006)]
Iron core collapses in ~0.1 s, at a free-fall velocity of ~c/4
Type II supernovae result from the death of a massive star
35
[Hillebrandt, Sci. Am., 43 (Oct. 2006)]
Shock
Rebound occurs when core reaches nuclear density, launching a strong shock
At nuclear density,ρnuclear~ 2 x 1014 g/cm3,the Earth would have a radius of only ~192 m
A “nuclear shock” is strong: Pshock ~ 1 MeV / fm3 ~ 1021 Mbar
200 km
ProtoneutronStar
Type II supernovae result from the death of a massive star
36
[Hillebrandt, Sci. Am., 43 (Oct. 2006)]
The shock stalls, due to the in-flowing matter, then gets revived in ~1 s by neutrino heating and the Standing Accretion Shock Instability (SASI)
Shock
ProtoneutronStar
Type II supernovae result from the death of a massive star
[Hillebrandt, Sci. Am., 43 (Oct. 2006)]
37
The shock breaks out from the surface of the star in 1-2 hr, and the star blows up as a SN
Stalled shock restarts, then r-process nucleosynthesis occurs for the next ~10 s
ProtoneutronStar
Type II supernovae result from the death of a massive star
38
[Hillebrandt, Sci. Am., 43 (Oct. 2006)]
107 km
Turbulence mixes core (blue) into the overlying He mantle (green) and H envelope (red). Some fraction of the core, carrying the synthesized heavy elements, gets ejected.
t = 5 hr
P. Drake et al. are developing designs to recreate a scaled supernova explosion on NIF
39
Scaled SN1987A on NIF
Z-axis (mm)
Rad
ius
(mm
)
Ti core
0.5 g/ccCRF
0.05 g/ccCRF
0 7
7
Z-axis (mm)
5
0
t = 200 ns(1500 s in SN)
0.4 0.08 0.02
0R
adiu
s (m
m)
6
Density (g/cm3)
• Simulations show deep nonlinear mixing relevant to SN1987A• Rho-t scaling described in Ryutov et al., Ap.J. 518, 821 (1999); Ap.J. Suppl.
127, 465 (2000); Phys. Plasmas 8, 1804 (2001)]• fully developed turbulence will be experimentally studied at NIF
Simulation of Proposed Experiment
Drive beams
Concentric Hemispherical
Shells
Two rippled
interfaces
HED Plasma induced excited state population is believed to play a role in s-process nucleosynthesis
Z
N
S-process conditionskBT≈8, 30 keVρ≈50-100 g/cm3
s-process path near Tm
169Tm 170Tm 172Tm
171Yb 172Yb 173Yb170Yb
171Tm
5.025 keV4.8 ns
3/2+
1/2+
171Tm
Dope ICF capsule with Tm, capture products from debris, measure ratio of 172/170 to determine s-process cross section enhancement factors
Plasma pulse amplification and compression at NIF can produce unprecedented intensities on target
41
• What happens at 1025 W/cm2 ? =>photon pressure ~ 1010 Mbars
• Can we learn how cosmic accelerators work?
• Nature of laser-matter interaction at high energy & intensity
Extreme laser intensities
J. Ren, Nature Physics, 2007R. Kirkwood, Physics Rev. Lett., 1996Y. Ping Submitted PRL
R. Kirkwood, Physics of Plasmas 2007
Plasma pulse amplification and compression concept for NIF
42
• What happens at 1025 W/cm2 ? =>photon pressure ~ 1010 Mbars
• Can we learn how cosmic accelerators work?
• Nature of laser-matter interaction at high energy & intensity
Extreme laser intensities
We are just starting to develop science “platforms” to explore this new frontier of science
43
R. Jeanloz, T. Duffy, R. Hemley, Y. Gupta, P. Loubeyre, L. Stixrude, S. Rose, J. Wark, G. Collins
S. Rose, R. Betti, J. Meyer-Ter-Vehn, S. Atzeni, G. Collins
P. Drake, D. Arnett, A. Frank, T. Plewa, T. Ditmire, A. Takabe, B. Remington
Astro/Rad-transport & Hydrodynamics
G. Fuller, U. Greife, Z. Shayer, C. Brune, R. Boyd, L. Bernstein
N. Fisch, C. Niemann, C. Joshi W. Mori, B. Afeyan, D. Montgomery, A. Schmitt, B. Kirkwood
44