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Generation and x-ray diagnostic characterizationof matter at extreme astrophysical conditions
in the laboratoryP. Neumayer
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Extremes of Density and Temperature: Helmholtz Alliance "Cosmic Matter in the Laboratory"
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Extremes of Density and Temperature: Helmholtz Alliance "Cosmic Matter in the Laboratory"
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High energy density plasma physics
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Planetary science - Astrophysical observations
Precise data on planetswithin our solar system:Radius, mass, angular velocity, graviational moments, magnetic fields, surface temperature, chemicalcomposition, …
Exo-planets:Nearly 500 planets outside our solar system, and counting…M, a, R, …
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has to reproduce the observational data
IceX
Large-scale computing allows ab-initiocalculations of dense-matter properties
JUGENE (FZ-Jülich)
~300.000 cores>1015FLOPS
need equation-of-state overthe entire parameter range
from Nettelmann et al.,Astrophys. Journal, 683, 1217 (2008)
Modeling of the interior structure in planets
Advances in scientific computation and computing technology
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High-intensity drivers
Intense pulseparticle accelerators
X-Ray Free-Electron-Lasers
High-energy lasers
PHELIX (GSI)Omega (UR)
DRACO (FZD)
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We want to conduct experiments to test dense matter models, required for planetary structure calculations
Challenges:Theoretical• Strong coupling• Partial degeneracyExperimental• High density• low temperature
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10
100
1000
10000
0 5 10 15 20 25
BeCAl
X-rays required to get information from inside
Atte
nuat
ion
leng
th [µ
m]
x-ray energy [keV]
High density multi-keV x-rays requiredLow temperature no keV x-rays emitted
Employ „active diagnostic“
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sample
Typical experimental arrangementX-ray image
Samples of HED matter in the laboratory do not hold still!need a fast, bright source (typ. GW peak power in few ps)
x-ray source film
X-rays radiography measures mass density
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X-ray radiography of a shock front
∆t=5.6 ns 4.6g/cm3
2.3g/cm3
S. Le Pape et al., Phys. Plasmas 17, 056309 (2010)].
Careful calibration allowsabsolute density measurement
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X-ray radiography: tool to follow hydrodynamicalevolution of HED matter produced at FAIR
N. Tahir et al., New Journal of Physics 12 (2010) 073022
5x1011ions
LAPLAS (LAboratory PLAnetary Science)
Multiple shock reflection increases density near-isentropically
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K-alpha backlighter optimization at PHELIX
Hydro-calculations by An. Tauschwitz (EMMI) and M. Basko, PIC calculations by P. Gibbon and A. Karmakar (EMMI)
Target
η(L ehot)~10-30%
Kα
p, ions
MeVbremsstrahlung
0 2 4 6 8 10
0.0 0.5 1.0 1.5
0.0 0.2 0.4 0.61E-4
1E-3
0.01
0.1
1
10
100
1000
0 2 4 6 8 10
0.0 0.5 1.0 1.5
0.0 0.2 0.4 0.61E-4
1E-3
0.01
0.1
1
10
100
1000
1.5×1019 W/cm21018 W/cm210191018
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K-α
He-α
K-β
coun
tspe
r bin
7.0 8.0 9.5energy [keV]
8.57.5 9.0
0
100
200
K-alpha backlighter optimization at PHELIX
P. Neumayer et al., Phys. Plasmas 17, 103103 (2010)
1017 1018 10190.01
0.1
1
data 1-Temp. PIC HXRD
NK
α,n
on-re
fl/ N
Kα,
refl.
Laser intensity [W/cm2]
Modeling of the K-alpha yieldExperimental setup
X-ray spectrometers
Cu,10µm
Al,5000µm
Laser pulse,100J, 0.7-10 ps
Refluxing electrons can make up >95% of the total K-alpha yield!
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Collaboration with PHELIX laser operations team: Implementation of 2-beam capability at PHELIX
Adjustabledelay
50:50Beamsplitter
Serratedaperture
Serratedaperture
Glass plate at brewster angle,half side HR coated
Adjustabledelay
50:50Beamsplitter
Serratedaperture
Serratedaperture
Glass plate at brewster angle,half side HR coated
PHELIX frontend
PHELIX Main-amp
PHELIXPre-amp
PHELIX PWpulse compressor
targetchamber
Beams from PHELIX laser pulse compressor
Beam split&delay Individual focusing of 2 full beams
Together with Prof. D. Batani, Univ. Milano: Proposal P046Development of high-resolution x-ray radiography at PHELIX
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Having such bright x-ray sources…
… can we do more than (just) followinghydrodynamic evolution and measure density?
Yes, we can!
X-ray Thomson Scattering
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X-ray scattering as a diagnostic of plasmas at high-energy density
Chihara, PRE (2000), Gregori et al, PRE (2003)
Ion feature Electron feature Bound-free
Z f See0 (k,ω) + Zb ˜ S ce (k,ω −ω ')Ss(k,ω ')dω '∫S(k,ω) = f I (k) + q(k) 2 Sii(k,ω) +
( )ωσω
σ ,dd
d
0
1Th
2
kSkk
=Ω
E0
~T½
EC
energysc
atte
red
inte
nsity
Simple picture:
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Scattering regime for electron structure factor See
1/kS > λD scattering on collective excitations (“plasmons”) ne
Scattering vector |kS| = 4π E0/hc sin(θS/2)
θS
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XRTS on shock compressed matter to measure staticstructure factor: Test of dense matter models models
A. L. Kritcher et al., PRL 103, 245004 (2009)
ρ/ρ0=1, T=0.025eV ρ/ρ0=2.7, T=2eV
(B. Holst, R. Redmer, U-Rostock)
FT-DFT-MD results
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Insulator-metal transition and corrections to theelectron response
P. Neumayer et al., PRL 105, 075003 (2010)
-100 -50 0 50
coldcompressedsource
energy [eV]
Cold, solid B is an insulator>1.6 Mbar pressure IMT free electrons
-100 -50 0 50
coldcompressedsource
energy [eV]
Strongly correlated electron gas local field corrections
Plasmon damping due to e-i-collisions
From J. Zhao et al.,PRB 66, 092101 (2002)
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The „National Ignition Facility“ (Livermore/CA, USA)
Ignition and burn by laser-driven inertialconfinement is expected within
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2009 call for proposals for fundamental high-energy-density science experiments at NIF in FY2010-2012
EMMI proposal for N
IF facilitytime
Characterization of
matter at extreme
densities
using x-ray Thomso
n scattering and ra
diography
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We will use NIF to compress matter extreme densitiesof >20x solid, while staying on low isentrope
14 15 16 17 18time [ns]
100
200
posi
tion
[µm
]
Mass density [g/cc]0 201010 10
17 ns
17.5 ns
18 ns
0
0 20
0.001
0.01
0.1
1
10
0 5 10 15 20
time (ns)
pow
er (T
W)
Drivelaser
Use NIF pulse shaping capability to launch multiple successive shocks
0 4 8 12 16 200
10
20
30
40
tem
pera
ture
[eV
]
density [g/cm3]
4e146.5 ns
3e13/3e14/3e1514 / 3 / 1 ns
1e154.5 ns
4e13/2e1411 / 5 ns
2e14/2e158 / 3 ns
3e1315 ns
4e13/4e1412 / 3 ns
3e13/3e14/1e1512 / 2 / 1 ns
rs=2 rs=1
Te/TF = 0.2
T e/T F= 0.
5
T e/T F
= 1 Γ C
C= 2
ΓCC = 5
ΓCC = 10
Rad-hydro calculations of multi-shock compression at NIF
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Multi-angle X-ray Thomson scattering and radiography characterize the compressed material
Multi-channelspectrometerdesign
NIF target chamber
Experimental setup
Target stalk(to Tarpos)
32 drivebeams
96 backlighterbeams
Au-shield
CH target
Scatteredradiation
DIM(0,0)
TCC
~600
mm
GXD
Curvedcrystals
shield
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XRTS – the ideal x-ray source…
… are X-ray Free-Electron-Lasers (FEL)• Well-collimated beam can access large scale lengths•
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We have joined the FLASH-TS collaboration
HiTRax
FFSS H-dropletsource
FLASH(@13.5nm)
Laser(20mJ, 80fs)
Forward scatteringspectrometer (by EMMI)
FEL
Wide-angle spectrometerdevelopment
October 2010
October 2010: achieved laser-pump/FEL-probing
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Our targets at FLASH: Laser-heated droplets
• Currently at FLASH: Elaser~20mJ• Under consideration at FLASH II: >1J• At European XFEL: Eshort>10J
Droplets: „reduced-mass-target“Model for laser-droplet heating
(refluxing!)
Liquid H2-dropletsDroplet size: 20µm
FEL
Laser
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Where could we go with more laser energy
0 1 2 3
0
20
40
60
80
100
elec
tron
tem
pera
ture
[eV
]
laser energy [Joule]
dropletdiameter [µm]
20 30 50 100
Model prediction for droplet heating
eHot eColdlaser
adiabatic expansion cooling
ions
Ponderomotiveacceleration collisions
thermal ionization FLYCHK
K-shell ionization
2950 3000 3050 3100 3150
energy [eV]
inte
nsity
[arb
.u.]
Te [eV] 20 60 100 140 180
2950 2960 2970
510152025
2950 2960 2970
510152025
0 10 20 300
10
20
30
40
50
ratio
K-a
lpha
/K-b
eta
electron temperature [eV]
K-shell spectroscopy is suitable as a charge state/temperature diagnostic
Two-temperature equilibration model
ArK
L
MKα
Kβ
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Goal: heat droplet targets at PHELIX
Collaboration with R. Grisenti, Helmholtz-Nachwuchsgruppe HeliJet (Univ. Frankfurt)
Proposal 035: Micro droplet targets irradiated with high-intensity laser pulses
•Cryogenic liquid beam•Triple-point chamber•Piezo-excited Raleigh breackup
S. Toleikis, M. Harmand (DESY), A. Kalinin, R. Costa Fraga, R. Grisenti (IKF, U-Frankfurt), A. Gumberidze, D. Hochhaus, B. Ecker, B. Aurand (EMMI/GSI), N. Winters, D. Winters, Th. Kühl (GSI), B. Zielbauer, T. Stöhlker (HI-Jena, GSI), J. Polz,
M. Kaluza (IOQ, FSU Jena, HI-Jena)
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Summary
PHELIXRMT
NIF3-shock
FAIRLAPLAS
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Thank you for your attention!
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