text optional: institutsname prof. dr. hans mustermann mitglied der leibniz-gemeinschaft scientific...
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Text optional: Institutsname Prof. Dr. Hans Mustermann www.fzd.de Mitglied der Leibniz-Gemeinschaft Prof. Dr. Thomas Cowan | Institut für Strahlenphysik | http://www.hzdr.de
Scientific Case for Ultra-intense Laser-Matter Interaction Physics in Solid-
density Plasma
Seite 2Prof. Dr. Thomas Cowan | Institut für Strahlenphysik | http://www.hzdr.de
Workshop on PW-Lasers at XFEL, 5-9.09.11, Dresden
Helmholtz Beamline at European XFEL: Scientific Motivation• Unique science enabled by combining European XFEL with ultra-intense lasers
- strong field QED, e.g., vacuum birefringence
• Highest quality x-ray probing of laser-driven experiments - isochorically heated matter (laser-ions, self- & externally-magnetized targets, interface collisional heating, laser-ablation-driven shocks)- ion induced damage in materials- time-resolved spectroscopy of excited-state chemical pathways- extreme fields & currents in ultra-intense laser-matter interaction- high pressure phenomena in laser-driven shocks- multi-view tomography, multi-frame imaging spectroscopy
• Add laser-based multi-species probing to XFEL experiments - proton radiography, fs-electron diffraction, hard bremsstrahlung,…
• Spin-offs- e.g., high-field X-ray Magnetic Circular Dichroism with small pulsed magnets- single-shot implementation of conventional synchrotron techniques
Seite 3Prof. Dr. Thomas Cowan | Institut für Strahlenphysik | http://www.hzdr.de
Workshop on PW-Lasers at XFEL, 5-9.09.11, Dresden
Helmholtz Beamline at European XFEL: Scientific Motivationns-pulse, kJ-class, ramped compression laser
create strongly-correlated matter at extreme pressure
Fundamental Goal: • precision & systematic study of P > 5 Mb cold matter
(advance beyond complex, expensive, single-shot laser expts)
Technique, requirements: • ramped-pulse isentropic compression solid-phase!!• laser-compression, XFEL probe• Rep-rate >0.1 Hz, with 10 Hz desired
Why Euro XFEL:• multi-user => “dedicated” HED beamline• not planned elsewhere (LCLS, SwissFEL, SCSS?)
Scientific Applications: • planetary science• fundamental solid-state• “new chemistry”
Seite 4Prof. Dr. Thomas Cowan | Institut für Strahlenphysik | http://www.hzdr.de
Workshop on PW-Lasers at XFEL, 5-9.09.11, Dresden
Helmholtz Beamline at European XFEL: Scientific Motivationultra-intense short-pulse PW-class (>100 TW) laser
hot-dense matter, and WDM generation probing of XFEL-driven WDM initiate dynamic processes & non-equilibrium conditions
Fundamental Goal: • precision & systematic study of near-solid density hot matter • systematic probing directly inside solid-density plasma
(advance beyond complex, single-shot laser expts)
Technique, requirements: • Isochoric heating with laser + XFEL (& laser-) probing
• WDM: laser-ions (~1 ps)• WDM & HEDP: laser-electrons, self- & external-B, interfacial shocks
• Isochoric heating XFEL (<50 eV) + Laser- probing (complements XFEL split+delay)
• Laser-initiation of dynamic & non-equilibrium phenomena in solid plasma (filamentation, transport, heating relaxation, diffusion)
• Ultrafast creation & probing • Rep-rate >0.1 Hz, with 10 Hz desired (move beyond complex, single-shot laser
expts)
Why Euro XFEL:• XFEL pulse-train-based synchronization to ~10 fs • not planned elsewhere at 100+ TW level
Seite 5Prof. Dr. Thomas Cowan | Institut für Strahlenphysik | http://www.hzdr.de
Workshop on PW-Lasers at XFEL, 5-9.09.11, Dresden
Helmholtz Beamline at European XFEL: Scientific Motivationultra-intense short-pulse PW-class (>100 TW) laser
hot-dense matter, and WDM generation probing of XFEL-driven WDM initiate dynamic processes & non-equilibrium conditions
Scientific Applications: • fundamental physics in P-T- regimes accessed by isochoric heating• WDM & HED plasmas in strong B fields• fundamental study of dynamic & non-equilibrium phenomena in solid
plasma (filamentation, e-transport, rad-transport, ionization, radiation, heating, relaxation, magnetic diffusion, anomalous & collisional resistivity)
Goal: Predictive understanding of ultra-intense laser-matter interaction
control & improvement of laser-ion acceleration, compact radiation sources for application in research, medicine & industry(e.g., better backlighters, ion sources, ultrafast probing…)
Seite 6Prof. Dr. Thomas Cowan | Institut für Strahlenphysik | http://www.hzdr.de
Workshop on PW-Lasers at XFEL, 5-9.09.11, Dresden
Helmholtz Beamline at European XFEL: Scientific Motivationultra-intense short-pulse PW-class (>100 TW) laser (II)
initiate radiation-induced processes in materials, bio, chemical systems
Fundamental Goal: • access the dynamics of particle-induced damage in materials• study fundamental atomic-level “jump” processes in materials• systematic study of chemical & biophysical processes initiated by radation
• Technique, requirements: • Sample irradiation with laser-generated ions, electrons, x-rays, -rays,
neutrons…(NB: optical pumping does not require TW-PW class)
• Probe with XFEL, complementary laser-generated probes (?)• Ultrafast creation & probing • (Rep-rate >0.1 Hz, with 10 Hz desired )?• Key challenge to identify best probing techniques (XANES, EXAFS, diffraction,
XCPS?…)
Why Euro XFEL:• 100+ TW for secondary particle & radiation production, not planned elsewhere
GOAL: Predictive understanding of fundamental materials processes at atomic- and nano-scale
Seite 7Prof. Dr. Thomas Cowan | Institut für Strahlenphysik | http://www.hzdr.de
Workshop on PW-Lasers at XFEL, 5-9.09.11, Dresden
Helmholtz Beamline at European XFEL: Scientific Motivationultra-intense short-pulse PW-class (>100 TW) laser (III)
Strong-field physics nuclear physics???
Fundamental Goal: • directly measure polarization of QED vacuum• …
• Technique, requirements: • Vacuum birefrigence measured with XFEL x-rays• ….
Why Euro XFEL:• 100+ TW for strong optical fields, not planned elsewhere• …
Seite 8Prof. Dr. Thomas Cowan | Institut für Strahlenphysik | http://www.hzdr.de
Workshop on PW-Lasers at XFEL, 5-9.09.11, Dresden
Laser Isochoric Heating
Self-generated magnetic confinementRassuchine et al., PRE 79, 036408 (2009)
Pulsed external ~MG magnetic transport inhibition
Bakeman et al., Megagauss XI (2007) http://conferences.theiet.org/mg-xi/mgxi-final-v7.0.pdf
Interface shock heating in heterogenous solid targetsSentoku et al., Phys. Plasmas 14, 122701 (2007)
Isochoric heating with laser-accelerated protonsPatel et al., Phys. Rev. Lett. 91, 125004 (2003)
Electrostatic hot electron confinement using reduced-mass targets
Perez et al., Phys. Rev. Lett. 104, 085001 (2010)
Seite 9Prof. Dr. Thomas Cowan | Institut für Strahlenphysik | http://www.hzdr.de
Workshop on PW-Lasers at XFEL, 5-9.09.11, Dresden
Short-pulse laser heating can access extreme states of matter
Confinement to increase Tion, ne+; and to probe EOS- inertial (e.g., large target heated with ion beam)- electrostatic (e.g, sheath fields)- magnetic (external, or self-generated)
Relativistic positron-electron
"plasma"
Hot coronal plasma (collisionless)
Isochoric heating (at depth)- resistive return current- electron cascade (hot warm ions)- electrostatic ion shock- secondary beam
Seite 10Prof. Dr. Thomas Cowan | Institut für Strahlenphysik | http://www.hzdr.de
Workshop on PW-Lasers at XFEL, 5-9.09.11, Dresden
H. Yoneda, 2008 WDM Winter School
Seite 11Prof. Dr. Thomas Cowan | Institut für Strahlenphysik | http://www.hzdr.de
Workshop on PW-Lasers at XFEL, 5-9.09.11, Dresden
1013 A/cm2, > 1000 T, 1013 V/m, ~keV solid density
Extreme Ex
Electron transport & strong fields in laser-driven targets
Extreme current densities, magnetized current filaments, and strong quasi-static magnetic fields in ultra-intense laser-matter interactions
Current filamentation
Quasistatic 5000 T fields in shaped targets, electron transport inhibition, enhanced heating
J. Rassuchine et al, PRE 79, 036408 (2009)
Important for:
Laser-ion accelerationIsochoric heatingFast Ignitor physicsLaser-plasma x-ray sourcesMagnetized HEDP
Seite 12Prof. Dr. Thomas Cowan | Institut für Strahlenphysik | http://www.hzdr.de
Workshop on PW-Lasers at XFEL, 5-9.09.11, Dresden
Extreme Ex5000 Tesla quasi-static field x-ray Faraday rotation imaging
dzBnK ze 2with K= 2.629×10-13 M.K.S. units.
LCLS-Matter in Extreme Conditions (HEDP) concept paper (04.2009):
“Relativistic electron transport, isochoric heating, and multi-MG magnetization
in solid density plasma” T.E. Cowan, M.S. Wei et al., (HZDR, UCSD, LANL, LLNL)
Concept – image B-fields by x-ray Faraday rotation
Channel-cut Si cyrstals: I. Uschmann et al, HI-Jena
Seite 13Prof. Dr. Thomas Cowan | Institut für Strahlenphysik | http://www.hzdr.de
Workshop on PW-Lasers at XFEL, 5-9.09.11, Dresden
Channel cut Si 400 crystal
Realization – use channel-cut Bragg crystal polarimeter
I. Uschmann et al, “Determination of high purity polarization state of x-rays,” ESRF expt. (2010)
(5 x 10-10 polarization)
Seite 14Prof. Dr. Thomas Cowan | Institut für Strahlenphysik | http://www.hzdr.de
Workshop on PW-Lasers at XFEL, 5-9.09.11, Dresden
Prof. Dr. Thomas Cowan Institut für Strahlenphysik www.fzd.de 29. September 2010
Open questions & future directions
• Begin with proof-of-principal (ride-along desirable)
• Imaging through channel-cut crystals appears feasible (in progress)
• Collimation requirements (diverging, or collimated with post-magnification)
• Feasibility of post-magnification (convex Bragg mirror)?
• What is short-pulse laser intensity, pulse energy available at LCLS?MEC: 35fs/150mJ/800nm; 2-20ns/2x25J/527nm
• Interesting directions: - fields in pre-formed plasma during hole boring- radial propagating near-surface fields- filament propagation in solid (ionization, heating, Weibel)- quasi-stationary fields from current filaments- magnetic diffusion (relaxation, >6 ps)- quasi-static resistive fields- material dependence
Prof. Dr. Thomas Cowan Institut für Strahlenphysik www.fzd.de 29. September 2010
Example: material dependence
• Filamentation in 6×1019 W/cm2, 300 fs, 20 J irradiation of Al, Cu, Au
• Resistive B-field evolution:
η - collisional resistivity
• in Al, dominant. B 5 MG Individual filaments.
• in Au, dominant. B 100 MG Confines net electron flow.
• in Cu, both important.
(-1)ne B┴ Zavg
theo: Y. Sentoku, A. Kemp; exp: J. Fuchs, T.E. Cowan et al
Al
Cu
Au
± 5 MG
±100 MG
±100 MG
Prof. Dr. Thomas Cowan Institut für Strahlenphysik www.fzd.de 29. September 2010
FLASH experiment
• Larger Faraday rotation with longer wavelength FLASH?
• RAP Bragg crystal (2d = 26.2 Å). n= 2d sin(45°) = 1.85 nm (670 eV)
• RAP “channel cut” in development at HI-Jena (I. Uschmann)
• 3rd harmonic operation, 1.85 nm, 670 eV (flux?)
• 10 m Al sample possible (FLYCHK)
for 10 eV Al, OD = 5 > 60 eV Al, OD < 1
• Expected signal?
Te
10 eV
60 eV
110 eV
….
…
…
410 eV
.
670 eV
Prof. Dr. Thomas Cowan Institut für Strahlenphysik www.fzd.de 29. September 2010
MG
150
100
50
0
-50
-100
-150
4
2
0
-2
-4/n
αe d
z (µ
rad
/nc µ
m)
Magnetic field Bz
laser
Rotation/(density x thickness)
y
x
z
2 µm
2 µm
laser
Maximum rotation at 250 nc, 1 µm thickness would be ≈ 1 mrad
Simulation: 2D3V PIC (picls), 10 nc, 1 µm foil thicknes, 1020 W/cm2. Output taken at 10 fs before pulse maximum
FLASH experiment -- cont’d
Simulation (T. Kluge, 1 m thick foil -- transient fields)
Prof. Dr. Thomas Cowan Institut für Strahlenphysik www.fzd.de 29. September 2010
FLASH experiment - cont’d.
• Expected signal
dzBnK ze 2with K= 2.629×10-13 M.K.S. units.
= 1.86 nmne = 6x1023 cm-3 = 6x1029 m-3 (solid density hot Al)Bz = 100 T / MG
= 54.6 mrad * ( B[MG] * z[m] )
for 5 MG & 10 m, = 2.7 mrad(or 50 MG & 1 m)
Al foil
CPA beam
FLASH 3rd harmonic
FR image
transmissionimage (Te)
RAP analyzer
(x,y) ≈ FR image ÷ transmission image
Seite 20Prof. Dr. Thomas Cowan | Institut für Strahlenphysik | http://www.hzdr.de
Workshop on PW-Lasers at XFEL, 5-9.09.11, Dresden
2D space-resolved x-ray absorption spectroscopy
Self emission spectroscopy t ~ 5-10 ps
Bulk electron temperature Tbulk ( x, y, t )
Space-averaged spectrum
with D. Thorn, T. Stoehlker (HI-Jena, GSI), M. Harmond, S. Toleikis (DESY)
Electron transport & ionization dynamics
Seite 21Prof. Dr. Thomas Cowan | Institut für Strahlenphysik | http://www.hzdr.de
Workshop on PW-Lasers at XFEL, 5-9.09.11, Dresden
Streaked optical emission
7400 7600 7800 8000 82000
200
400
600
800
1000
1200
B-like
Mg-like
F-like
Be-like
In
ten
sity (
a.u
.)
Energy in 5th Order Diffraction (eV)
L-Shell (1st order), K
ß (6th order)
O-like
Laser pulse
Electron Beam X-ray pulse
Laser-driven electron transport & ionization dynamics
1013 A/cm2 , 1013 V/m, >1000 T, ~keV solid density
Z=6ni=4•1022 1/cm3
ne=Z•ni
Ti(0) = 0Th(0)= 30keVTc(0)= 1keV/Z
I=2•1017W/cm2
Pulse length = 700fsTarget = 10mnh=10•1021 1/cm3
Collisions, electron diffusion by scattering, and radiative energy loss have now been included in simulation.
Ion temperatures of several 100 eV, at solid density (Z=6) for up to a few ps, may be possible with the “Tomcat”-Zebra coupling.
(Experiments at UNR begun in December 2005.)
(Y. Sentoku, A. Kemp, M. Bakeman et al.)
Seite 23Prof. Dr. Thomas Cowan | Institut für Strahlenphysik | http://www.hzdr.de
Workshop on PW-Lasers at XFEL, 5-9.09.11, Dresden
NEEC/NEET with Short Pulse LaserNuclear Excitation by Electron Capture with ultra-intense short-pulse lasers:
• 169Tm NEEC at Draco 150 TW laser @ HZDR (Jupiter @ LLNL?)• Isochoric heating to keV temperatures (Sentoku et al, PoP 14, 122701, 2007) • Streaked spectroscopy for 4 ns, 8.4 keV
A. Kritcher et al.,JINA Workshop, London
March 13, 2011
150 TWfew Hz
X-ray Streak
t
conicalHOPG
Au / 169Tm / Au target
atomic nuclear
ML
Seite 24Prof. Dr. Thomas Cowan | Institut für Strahlenphysik | http://www.hzdr.de
Workshop on PW-Lasers at XFEL, 5-9.09.11, Dresden
“Isochoric heating in heterogenous solid targets with ultrashort laser pulses,” Sentoku, Kemp, Presura, Bakeman and Cowan, Phys. Plasmas 14, 122701 (2007)
Au layers
169Tm layer
4 J, 25 fs< 10 Hz
• few keV• 10 g/cc• few ps
NEEC/NEET with Short Pulse Laser
Seite 25Prof. Dr. Thomas Cowan | Institut für Strahlenphysik | http://www.hzdr.de
Workshop on PW-Lasers at XFEL, 5-9.09.11, Dresden
NEEC/NEET with Short Pulse Laser
• Potential for 1st observation of NEEC• Short-pulse separates excitation from decay• Repetition rate for signal averaging & systematics• Resolve unknowns, e.g., Lifetime vs. Plasma Temperature
• High-rep-rate 150 TW laser “Draco” at HZDR• tamped targets – short-pulse isochoric heating• large collection Bragg spectrometer• Fast X-ray streak, few ps (R. Shepherd)• Slow X-ray streak, few 100 ps (R. Shepherd)
A Kritcher et al., JINA Workshop,
March 13, 2011, London
• kT ~ keV, ~ few ps, n ~ solid density, 10 m3
• Rate ~107 /s, Int. Conv. =263.5
N ~ (1012 nuclei)(107 s-1)(10-12 s)(1/~ 104 per shot
Signal: (~ few / shot) × (few shot / s)
150 TWfew Hz
X-ray Streak
t
conicalcrystal
Au / 169Tm / Au target
Seite 26Prof. Dr. Thomas Cowan | Institut für Strahlenphysik | http://www.hzdr.de
Workshop on PW-Lasers at XFEL, 5-9.09.11, Dresden
Detailed simulations of “shock” heating in CD2/Al/CD2: Lingen Huang, T. Kluge, M. Bussmann, et al.and planning for Callisto (LLNL) experiment: B. Ramakrishna, R. Shepherd et al.
NEEC/NEET with Short Pulse Laser
Longitudinal Electric Field Deuteron Density
1020 W/cm2 150 fs
Seite 27Prof. Dr. Thomas Cowan | Institut für Strahlenphysik | http://www.hzdr.de
Workshop on PW-Lasers at XFEL, 5-9.09.11, Dresden
Nuclear physics and Anti-matter creation with ultra-intense lasers
APS News 8, No. 3, March 1999
APS Centennial Meeting HighlightsAtlanta, March 1999
Relativistic laser-matter interactions open new vistas…
At I = 1021 W/cm2 :
• Eo ~ I1/2 = 1014 V/m
• Bo = Eo/c = 300.000 Tesla
Atoms are ionized and electrons
accelerated to >20 MeV in half-cycle
3 J / 20 fs1020 W/cm2 e-
B > 1000 Tesla
sc ~ 10 MV
Rückstrom
Pre-formed plasma
Seite 28Prof. Dr. Thomas Cowan | Institut für Strahlenphysik | http://www.hzdr.de
Workshop on PW-Lasers at XFEL, 5-9.09.11, Dresden
plasma wavelength < pulse length
e-
(a0=5)
We shall consider gaseous and solid density targets