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Home , Degenerate matter

Probing highly compressed degenerate and matter at extreme Gbar pressures at NIF

Presentation to NIF User Group Feb 13, 2012 A. Kritcher Liaison scientist for NIF proposal, Postdoctoral Fellow P. Neumayer, R. Falcone, D. Swift, J. Hawreliak, H. Lee, R. Redmer, E. Foerster, C. Fortmann, S. Le Pape, G. Hays, S. Rose, R. Hemley, R. Jeanloz, D. Hicks, P. Cellier, J. Eggert, D. Milathianaki, T. Doeppner, O. Landen, G. Collins, S. Glenzer Matter at >20x compression and pressures of Gbar can only be reached and probed with XRTS and radiography at NIF

• Matter at extreme densities occurs in astrophysical objects such as giant planets and highly evolved ! • At extreme densities matter becomes metallic. The are strongly coupled due to the small inter-particle distance and the high charge state.

• coupling decreases at higher density, due to the increasing Fermi-energy • Matter at extreme pressures of Gbars (and higher temp) occurs in the cores of super-giant planets and stars! • Fundamental physics including EOS and of condensed matter up to Gbar pressures is important for understanding the evolution of these astrophysical bodies

Measurement of X-ray scattering & microscopic properties! X-ray radiography! & parameters !

NIF-0000-00000s2.ppt Author—NIC Review, December 2009 2 These joint proposals include many outside collaborators from several institutions • GSI, Germany: ! • P. Neumayer ! • Univ. of California Berkeley, USA/LBNL, USA: ! • R. Falcone, R. Jeanloz • LLNL, USA! • D. Swift, J. Hawreliak, S. Le Pape, D. Hicks, P. Cellier, J. Eggert, T. Doeppner, O. LandenG. Collins, S. Glenzer ! • LCLS, USA! • H. J. Lee, D. Milathianaki, G. Hays • Univ. of Jena, Germany • E. Foerster, et al. • Univ. of Rostock, Germany ! • R. Redmer, et al. • Univ. of California Los Angeles, USA! • C. Fortmann • Imperial College London! • S. Rose, et al. • Carnegie Institute of Washington! • R. Hemley, et al. NIF-0000-00000s2.ppt Author—NIC Review, December 2009 3 Experiments at NIF will compress matter to densities of >20x solid, while staying on a low isentrope, using multiple shocks

Laser Requirements: CH will be directly driven in a planar geometry and probed with x-rays Drive (8 quads): 3-5kJ/beam, focus= 1mm 8 Quads XRTS Probe beams (12 quads): 75/beam (100-160 (88ps impulse) or 4-5 kJ/beam (NIF Pulse), focus= 250μm kJ) ! Radiography Backlighter (2 quads): 4-5 kJ/beam (NIF Pulse), focus= 1mm 2 Quads Drive Pulse Shape: BL Pulse Shape (NIF): (16-40 kJ)

12 Quads (3.6-240 kJ)

A new spectrometer snout for XRTS is being developed…

(PI) P. Neumayer, et al.

NIF-0000-00000s2.ppt Author—NIC Review, December 2009 4 Diagnostic configuration and compatible NIF platforms for planar high compression experiments

Experimental layout, w.r.t. Diagnostics Configuration: target chamber Diag! Location! Priority! Type! Calib!

DIM 0-0 GXD or hGXI! 90-78! Essent 3! Pre-Shot! ial! hGXI or GXD 0-0! Essent 1! Pre-Shot! 90-147 TARPOS +Supersnout 2 ial! TASPOS or MAHS! SXI 1! 161-326! Ride- 3! Pre-Shot! along!

Compatible diag configurations: DIM 90-78 1) (DT4 for DT & ConAW) shown to the left 2) DT3 for DT & ConAW 3) DT2 for DT & keyhole

SXI 161-326

NIF-0000-00000s2.ppt Author—NIC Review, December 2009 5 Pulse shaping enables creation of highly compressed and strongly coupled matter at relatively low

Densities and temperatures at shock We can reach 20x

coalescence single- or multiple shocks comp at 20 eV 40 (red dots)100 18 1e15 Mbar 4.5 ns 17 50 units of 20 Mbar 30 W/cm2 10 2e14/2e15 16 Mbar 8 / 3 ns

Mbar [ns] time 15 3e13/3e14/3e15 20 4e14 6.5 ns 14 / 3 / 1 ns 14 20

10 [eV] 10 3e13/3e14/1e15 12 / 2 / 1 ns 4e13/4e14 18 ns 12 / 3 ns 3e13 4e13/2e14 10 15 ns 11 / 5 ns 17.5 ns 0 10 Mass density [g/cc] density Mass 0 4 8 12 16 20 17 ns 3 0 density [g/cm ] 0 100 200 position [µm] 3-shock comp (PI) P. Neumayer, et al.

NIF-0000-00000s2.ppt Author—NIC Review, December 2009 6 In these experiments X-rays are scattered from plasma to determine plasma parameters

X-ray Scattering p=hν’/c We Scatter x-rays from X-ray Source Scattered X-rays electrons in the plasmas.

Electrons absorb the photon, p=hν/c oscillate, and re-emit the x λs radiation. pe=meν Elastic (Rayleigh): E of incident photon is conserved I.P. -Tightly Bound e- : Binding Energy > Compton Energy (∆E ) hνS c hν i Inelastic (Compton or Plasmon):

-Weakly Bound e- : hνS Binding Energy < Compton Energy (∆Ec) hνi -Free e-

hνi Free electron O. L. Landen et al., JQSRT 71, 465 (2001) hνS

NIF-0000-00000s2.ppt Author—NIC Review, December 2009 7 The non-collective and collective scattering will be applied to observe the micro and macroscopic motion of the electrons Scattering Parameter: Plasma Screening Length: α "S 1 # Fermi-degenerate Classical " = $ Plasma: Plasma: k# # 1/ 2 1/ 2 s s $ 2 1/ 3' $ ' ! $ # ' #okTe " = & ) " = 4% TF & 2 & ) ) D & 2 ) k = sin(& /2) 4mee % 3ne ( ! % nee ( % ( #o

Non-Collective Scattering Collective Scattering ! ! Probing: > ( > 1) ! Probing: λ < λS (α < 1) λ λS α

Backward Forward scattering scattering v! v!

! Detector Detector λS λS! k λ ∼ 1/k! λ ∼ 1/k! ks k k s θ θ k 0 ko S. H. Glenzer et al., PRL (2003) S. H. Glenzer et al., PRL (2007)

NIF-0000-00000s2.ppt Author—NIC Review, December 2009 8 The plasma parameters can be determined from the shape of the scattered spectra

7 3 Non-Collective Scattering Spectra Collective10 Scattering Spectra 30_z1p_2p0e23_7peV_Ti7n 11:03:08 PM 10/28/2007

0.064 Elastic 0.056 Te=Ti=10 eV Peak

0.048 Te=Ti=7 eV Ti Ti Te=Ti=3 eV 0.04 7 3 10 Detailed30_z1p_2p0e23_7peV_Ti7n 10:16:36 AMBalance 10/29/08 0.002

B 0.032 0.0015 B 0.001 T 0.024 0.0005 e

0 4460 4480 4500 4520 4540

A 0.016 Intensity (A. U.) (A. Intensity Intensity (A. U.) (A. Intensity Plasmon

0.008 ne

0

8.2 8.4 8.6 8.8 9.0 9.2 4.454460 4.484480 4.54500 4.524520 4.544540 Energy (keV) Energy (keV) A

Partially Degenerate: Detailed Balance: (Blue Feature) Take Width à TF (ne) energy from plasmon wave ~e-∆ω/kT Steepness of the red wing à Te Non Degenerate: 1/2 ∆ ω ~ ωpe ∝ne Width à Te NIF-0000-00000s2.ppt Author—NIC Review, December 2009 9 The Intensity of the elastically scattered X-rays is Directly Related to the Structure Factors

Total Cross-Section Includes Free, The Scattering Intensity Depends on Tightly, and Weakly bound States the Material Structure

2 S (k, ): Probability of finding an at a d " k ii ω * = " 1 S(k,$) given distance from another ion (k space). d d T k # $ o S(k,") = g(r) g(r) g(r) o Z f See (k,!) ! Electron Feature ! ! ! 0 2 4 6 0 2 4 6 0 2 4 6 ˜ r/a r/a ! +Zc $ S ce (k," #"')Sce (k,"')d"' r/a

Bound-Free Feature

2 + f (k)+ q(k) S (k,!) ! 1 ii Solid Crystalline -Like Gas-Like Structure Structure Structure Ion Feature

When atoms are less structured there is more of a probability to scatter at an arbitrary angle (less coupling) ==> S(k,w) becomes smooth

*J. Chihara, J. Phys. Condens. Matter 12, 231 (2000) NIF-0000-00000s2.ppt Author—NIC Review, December 2009 10 By probing multiple scattering angles we can study ion structure in highly degenerate plasmas

We can test models of material structure at • Study ion correlations via high Temp & densities that predict ion-ion elastically scattered photons off correlations and calculate EOS (DFT-MD)

of bound electrons (measure scattered intensity) 12 3 ρ [g/cm ] 5 10 10 15 • Position of the correlation peak: 8 20

à Wigner-Seitz radius 6

• Sharpness of the correlation 4

peak: 2 ion feature scattering strength à Degree of ion-ion coupling 100 T [eV] i 8 T=10eV T=20eV • Scattering at large k (17.5 keV) T=30eV where Sii ~1 will enable 6 2 characterization of f (k) + q(k) 4

2 ion feature scattering strength

0 20 40 60 80 100 120 140 scattering angle [deg] Neumayer (PI), Kritcher, Glenzer, Lee, et al

(PI) P. Neumayer, et al.

NIF-0000-00000s2.ppt Author—NIC Review, December 2009 11 By probing multiple scattering angles we can study electron electron correlation in highly degenerate plasmas

Energy shift of plasmon from the

incident probe energy • Collective scattering includes scatter of electron plasma waves (plasmons)

• RPA is used to calculate the plasmon dispersion

• Deviation from mean field theory (RPA) due to short range local field corrections for the electrons results in a reduced plasmon shift or kinetic energy (e- more correlated)

k[1/A] 1 2 3 4 • Dispersion measurements in dense k/k 0.44 0.88 1.32 1.75 plasmas are directly related to e- F coupling, i.e. internal energy k/kF at NIF, 20x compression, Z =4, 8.6keV backlighter free P. Neumayer et al., PRL 105, 075003 (2010)

(PI) P. Neumayer, et al.

NIF-0000-00000s2.ppt Author—NIC Review, December 2009 12 A new multi-angle spectrometer will enable simultaneous probing of four scattering angles or k-vectors

New Multi-angle XRTS Spectrometer Specs for spectrometer snout

Angled View • Angles: ± 20 deg± 12 deg

• HOPG used for high reflectivity (3mrad), 6.35 cm LiF is used for better energy and spatial resolution

17.5 cm • (7x5cm) will be cylindrically/ conically bent with Ω=7x10-5/xtal =3x10-4total Side View 20° • Gated MCP’s, IP surrounding MCP and 12° full IP option

• Blast shield, filter options before the crystals and at the MCP, Tungsten block 17.5 cm 17.5 cm for direct line of sight of TCC to the MCP

LiF(200) ROC: 60 mm, 7.4-10.6 keV, first order Fabrication through Artep. HOPG ROC: 38 mm, 7.3-10.7 keV, first order

NIF-0000-00000s2.ppt Author—NIC Review, December 2009 13 Highly compressed and degenerate matter has been probed with XRTS from spherically imploded capsules at Omega

Schematic of the experimental Compressions of x7 and x13 times solid configuration density in CH and Be have been probed CH Raw data Profiles of the experimental data Zn Foil 7 BL beams (3kJ) Source OR 430µm 40µm thick

Au half-cone t=3.1 ns (6mm in length, 60 µm thick) t=3.9 ns 36 Drive Beams (15kJ) t=5.8 ns

t=8.1 ns

Scattering SNR of up to >200 (A. kritcher, et al. PRL) Spectrometer à Infer plasma properties such as adiabat and degree of ion-ion coupling (>5)

The high SNR of the data and sensitivity of the Compton-red wing enabled model independent determination of Te and ne (~20% for ne and Te, and 13% for adiabat)

NIF-0000-00000s2.ppt Author—NIC Review, December 2009 14 NIF enables the creation of conditions to study the cores of exoplanets (up to 2Gbar) and brown dwarfs using a fielded NIC platform

Solid spheres will be indirectly driven Laser Requirements: in a spherically convergent geometry Drive : 6.9kJ/beam, 1.3MJ total (NIF Solid, CH with ignition pulse (575)), focus= 1mm ° ° dopant, Be,B,C ° ° ! Al Ring XRTS probe and Radiography Backlighter (2 quads): 4-5 kJ/beam (NIF 40 um Au 10.01 mm ignition pulse (575)), focus=500μm B46 as DIM 90-78DISC/ Backlighters GXI on 5 µm Zn foil at 90, BL (3ns) and Drive Pulse Shape (NIF): 135

LEH FFLEX

FABS & Non-cryogenic: NBI Au wall, Au layer 36B FABS & 0.96 mg/cc 4He NBI DANTE filled 31B 57% Unlined LEH

Closely related to the NIC Con-A platform (D. Hicks) (PI) R. Falcone, et al.

NIF-0000-00000s2.ppt Author—NIC Review, December 2009 15 Diagnostic configuration and compatible NIF platforms for Gbar pressure experiments

Diagnostics Configuration: DT4 for HDT & ConAW Diagnostic list! Location! Priority! Typ Calib! e! nToF DIM 0-0 GXD or hGXI! 90-315 or Essential! 1! Pre-Shot! NAD hGXI 90-78! SPBT SXI-U 18-124 GRH hGXI 0-0! Essential! 1! Pre-Shot! FFLEX/eHXI +Supersnout 2 ! Arianne or MAHS!

DIM 90-315 SXI 2! 18,123! Ride- 3! Pre-Shot! DISC/ hGXI along! DIM 90-78 SXI 1! 161,326! Ride- 3! Pre-Shot! NI MRS foil along! OR hGXI per W. Hsing 90-77 Dante 1! 143,274! Ride- 3! Pre-Shot! TASPOS along! Dante 1143-274 Other compatible diag configurations: 1) (DT4 for DT & ConAW) shown to the left SXI-L 161-326 2) DT3 for DT & ConAW 3) DT2 for DT & keyhole

NIF-0000-00000s2.ppt Author—NIC Review, December 2009 16 The experimental choice of solid sphere target depends on transmission through the target and changes in opacity

Compromise: Solid spheres are used instead of NIC capsules to better constrain the mass • Transmission through sample density through profile fitting (small) vs spatial resolution Sample: diamond or graphite, 1 (large). mm diameter • Compressible: more heating => worry about opacity falling.

Best: C(diamond) with thick “ablator”

Possible: C(graphite), BN, B4C, with ablator; B or Be with or without ablator, doped CH Ablator: CH, 2 mm diameter,

doped with Ge/Br D. Swift, et al.

Diamond is also important for studying the structure of giant planets and advanced ICF ablator materials.

NIF-0000-00000s2.ppt Author—NIC Review, December 2009 17 Rad-hydro simulations show that we can reach >2 Gbar pressures for indirectly driven solid* targets *Carbon (dia) with thick ablator, 20 TPa drive C EOS: SESAME #7830SESAME CEOS:

LagJ (hyades) w/cold opac

D. Swift, et al.

NIF-0000-00000s2.ppt Author—NIC Review, December 2009 18 A mass density profile of the sample can be determined

from a radiographic image using Abel inversion Abel inversion: An integral transform that can be used to reconstruct a mass density profile from a projected radiographic image.

Known (assumption): Initial x- ray intenisty

Measured: Observed Determined: optical transmitted x-ray I(y) = I (y)e!! (y) depth along LOS (y) intensity along LOS (y) 0

Determined: Mass Determined (above): optical density profile depth along LOS (y)

1 " d$ dy ! (r)"(r) = ! Known (assumption): v # 2 2 Opacity profile at the BL # r dy y ! r Measured: radius energy

However… in addition to the assumptions, Abel inversion can amplify noise from photon statistics and backgrounds that is already an issue

D. Hicks, et al., PoP, 17 (2010)

NIF-0000-00000s2.ppt Author—NIC Review, December 2009 19 We plan to use solid samples and profile matching with Bayesian analysis to determination the mass density

profile

This Method • Bayesian analysis: – Use a density profile with adjustable parameters (e.g. nodes) and constraints – Simulate radiograph – Adjust parameters for best fit – Refine D. Swift, et al.

• Solid Target: Using known This method vs. Abel unfold unshocked density, captures shock jump much more accurately, even with noise and inaccurate profile of outer layers

D. Swift, et al.

NIF-0000-00000s2.ppt Author—NIC Review, December 2009 20 With the mass density profile determined and measured shock speeds we can constrain the EOS

Rankine-Hugoniot Relations: Re-arrange D2 relation:

2 2 p ! p0 D2 D = v0 p = p + (v ! v) v ! v 0 2 0 0 v0 2 u = (p ! p )(v ! v) ! p !(v ! v) !D !" !D 0 0 = 0 + 2 ~ + 2 p v v D D 1 0 ! " e = e0 + 2 (p + p0 )(v0 ! v)

D = Shock speed 1 Only depends on: ! = = Specific volume " -D: Shock speed (measured) -ρ: Mass density (determined) p = Pressure -P: Pressure (inferred) u = Particle speed e = Internal energy R. Falcone, D. Swift, et al.

à With P and ρ we determine the at Gbar pressures for CH and Diamond (Other materials under consideration: Be, B, doped CH)

NIF-0000-00000s2.ppt Author—NIC Review, December 2009 21 For non-degenerate plasmas the width of the Compton scattered feature is sensitive to Te

Sensitivity of x-ray scattering to Sensitivity of x-ray scattering to electron temperature changes in electron density

m3 m3 m3 m3 m3 m3

Normalized Normalized to elastic! to elastic!

Compton shift (eV)~154, TF (eV)~140

XRTS: is sensitive to temperature due to Doppler broadening in the non- collective regime at these temperatures and densities

NIF-0000-00000s2.ppt Author—NIC Review, December 2009 22 Current radiography experiments at Omega using solid spheres observe the shock front and initial densities have been estimated

Supporting Omega experiments are Measured radiographs400 of indirectly currently being fielded driven solid PAMS sample at Omega

200 BackLighter3

V – backlighter foil (4-7 keV) 2000 BL 0 2.5mm 1500 P7 P6 1.6mm 0.6mm TIM 4 - XRFC -200 Shock Front PAMS 20 beams/LEH 2.7 ns, max E 1000 Horizontal or vertical slit -400 TIM 3 – XRSC? XRFC? 500 0 200 400 600 800

T4-XRFC (2D radiograph), DANTE (Tr), T3- 100 80

XRS (BL), SSCA (streaked radiograph) 60 3

0 x10 40 J. Hawreliak, et al. 0 500 20 1000 1500 2000 0 5 10 15 20 3 x10 2.0

1.5

Preliminary: Meas. were in rough agreement with6 predicted shock velocities

1.0 x10

and shell thickness (LASNEX); inferred densities0.5 were lower than predicted

0.0 10 20 30 40 50 3 x10

NIF-0000-00000s2.ppt Author—NIC Review, December 2009 23 Summary and outlook

• We have shown that the ne and Te for plasmas of densities of up to x13 times solid density can be accurately characterized with XRTS

• At NIF we plan to probe highly degenerate and compressed plasmas (20eV and 20x compression) and plasmas at high pressure and temperature (>1Gbar and ~0.4 keV)

• Other supporting Omega experiments probe the EOS of CH in a solid-sphere geometry (J. Hawreliak) and develop high Z backlighters such as Mo K-a and He-a (T. Ma)

• There have been many more XRTS and radiography experiments at Omega and Titan that investigate ion structure in 2x or 3x solid density plasmas at low temperatures

NIF-0000-00000s2.ppt Author—NIC Review, December 2009 24 The end.

NIF-0000-00000s2.ppt Author—NIC Review, December 2009 25