Probing highly compressed degenerate matter 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 solid 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 gas planets and highly evolved stars! • At extreme densities matter becomes metallic. The ions are strongly coupled due to the small inter-particle distance and the high charge state." •! Electron 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 ionization 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! & plasma 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= 250"m! 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 temperatures 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 temperature [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 electrons 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' $ # kT ' & ! # ) " = o e 4% "TF = 2 & ) D & 2 ) & 4m e 3n ) n e k = sin(& /2) % e % e ( !( % e ( #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.) Intensity Intensity (A. U.) 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 ion 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 Liquid-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, Zfree=4, 8.6keV backlighter 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 •!Crystals (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.