ExtreMe Matter Institute EMMI Physics Days Indirectly heated plasma targets for combined Indirectly heated plasma targets for combined PHELIX laser - heavy ion beam experiments PHELIX laser - heavy ion beam experiments Olga Rosmej Olga Rosmej Plasma physics, GSI Plasma physics, GSI November 4-5, 2010, Darmstadt
Laser – Heavy Ion Beam Combined Experiments Laser-heavy ion beam combined experiments at GSI PHELIX-laser : 0.3 kJ @ 1-15 ns, 1 ω , 0.15 kJ 1ns 2 ω (October 2010) Target chamber Heavy ion beam (UNILAC) 1<Z<92, E=3–13 MeV/u, RF: 108/36 MHz Interaction of heavy ions with ionized matter : increased plasma stopping power 3ns ion bunch Stop l l a a s s e detector e UNILAC r r b b e e a a m m Z av , V av Ion beam Z 0 , V 0 TOF Target (1 μ m thick foil) EMMI Physics Days 4-5 November 2010 o.rosmej@gsi.de
Projectile ion energy loss in ionized matter Z p C C C C v p v orb plasma cold matter p C C C C 1. Increased energy transfer from the projectile ion to free plasma electrons 2. Increased projectile charge state due to suppression of the BEC in plasma Projectile energy loss in partially ionized matter ⎡ ⎤ ⎛ ⎞ π ⎛ ⎞ 2 2 2 Z 2 2 16 a I Z dE 2 m v 2 m v ∑ ( ) K − = − + ⎢ ⎥ 0 H ef f ⎜ ⎟ S ⎜ e S ⎟ e S Z Z n ln n ln ⎜ ⎟ ω K Z e � 2 ⎢ ⎥ ⎝ ⎠ dz m v I ⎝ ⎠⎦ ⎣ = Z 0 e S Z p Bethe-Bohr--Bloch bound electrons free electrons EMMI Physics Days 4-5 November 2010 o.rosmej@gsi.de
Increased ion energy loss in plasma H-plasma: N e ~10 17 cm -3 , T e ~1-2 eV Ca-U; 1.4 MeV/u 300 keV/u 84 Kr in H-plasma increase up to 30 times Laser produced plasma: N e ~10 21 cm -3 , T e ~ 0.1-1 keV EMMI Physics Days 4-5 November 2010 o.rosmej@gsi.de
Current schemes of the plasma target production Direct laser heating Heating with hohlraum radiation Ideal , non-uniform plasma: homogeneous plasma: Te~ 200 eV, n e < 10 21 cm -3 Te~ 30 eV, ne~10 21 cm -3 fully ionized partially ionized EMMI Physics Days 4-5 November 2010 o.rosmej@gsi.de
Expansion of the laser heated foil target In experiments on laser generated plasma, the energy is focused on to the target into a small spot of 10-100 μ m : High energy density plasma : 5 MJ/mm 3 λ = 1.064 μ μ I = 5.10 13 Wt/ cm E= 50J, t= 10 ns, d= 100 μ 2 I = 5.10 13 Wt/ cm 2 E= 50J, t= 10 ns, d= 100 real time-scale – 10 ns spatial scale – 100-1000 μ m ion 2500 μ Laser pulse temperature Red ~ 250 eV Red ~ 250 eV Green ~ 125 eV Green ~ 125 eV Blue ~ 50 eV Blue ~ 50 eV 5000 μ Initial target surface 2D –HD, M. Povarnitsin, JIHT, Moscow EMMI Physics Days 4-5 November 2010 o.rosmej@gsi.de
Strong gradients of the directly heated plasma Te n e 17 cm -3 3 10 17 10 cm - 10- -50 50 eV eV 10 0 2500 2500 10.00 20.00 30.00 1,000E-3 40.00 2000 2000 50.00 Target position 0,01000 laser 60.00 Target position 70.00 0,1000 80.00 1500 90.00 1500 1,000 100.0 R [mkm] R [mkm] 110.0 10,00 1e-4 120.0 130.0 1000 1000 1e-3 140.0 150.0 1e-2 160.0 170.0 500 180.0 500 190.0 1e-1 200.0 210.0 0 220.0 0 -4000 -3000 -2000 -1000 0 -4000 -3000 -2000 -1000 0 X [mkm] X [mkm] 70- -130 130 eV eV 180- -200 200 eV eV 70 180 10 18 18 cm cm - -3 3 10 20 20 cm cm - -3 3 10 10 Z mean 140- -170 170 eV eV 140 Ti 0 2500 4-6 Target position 0.5000 0 2500 1.000 10.00 1.500 20.00 Target position 2.000 2000 30.00 2.500 40.00 2000 50.00 3.000 60.00 3.500 70.00 1500 4.000 80.00 4.500 1500 90.00 R [mkm] 100.0 5.000 R [mkm] 110.0 8-10 5.500 120.0 6.000 1000 130.0 1000 6.500 140.0 7.000 150.0 160.0 7.500 170.0 500 8.000 500 180.0 8.500 190.0 9.000 200.0 9.500 210.0 0 220.0 10.00 0 -4000 -3000 -2000 -1000 0 -4000 -3000 -2000 -1000 0 X [mkm] X(mm) 3 2 1 X [mkm] 2D –hydrodynamics, M. Povarnitsin , JIHT, Moscow EMMI Physics Days 4-5 November 2010 o.rosmej@gsi.de
Why foams? Properties under the ion and laser beams: Properties under the ion and laser beams: 1. Higher conversion of laser energy in to the plasma temperature compared to the solid foils 2. Slow expansion dynamics ( ρ , T ~ constant during nanoseconds) 3. Fast ( ~sub ns) homogenization after laser 2 mv i T i T T e T heating i e 4. Energy broadening of the ion bunch caused by the porous structure has to be acceptable (no merging of the subsequent ion bunches) Small pore size is important! EMMI Physics Days 4-5 November 2010 o.rosmej@gsi.de
Heating of low Z foams by means of hohlraum radiation Project goal: creation of large (1mm X 1mm), homogeneous, long leaving ( >3 ns - length of the ion bunch) partially ionized plasma of n e ~ 10 20 -10 21 cm -3 λ =1,056 μ m, τ =1.4 ns, E= 200-270 J, PHELIX Laser: PHELIX Laser: d~200-300 μ m, I>10 14 W/cm 2 , contrast 10 -6 Target: Au-cylinder d=1.7mm, wall 10 μ m 1.7-2mm Au-foil 0.1 μ m E 0 E 1 Heavy ion beam CHO-foam 2-20 mg/cm 3 4-6 MeV/u areal density ρ x~ 150-500 mg/cm 2 d~500 μ m τ =3ns
International collaboration • VNIIEF-Sarov, Russia (ISTC 2264); Numerical optimization of the target design, experimental support • Rhein-Ahr-Campus Remagen, University of Applied Sciences, Germany experimental support (absolute calibrated transmission grating spectrometer) • Goethe University, Frankfurt am Main, Germany experimental support (X-ray diagnostics) • Joint Institute for High Temperatures, Moscow, Russia carbon plasma opacities calculations • Lebedev Physical Institute, Moscow, Russia foam target production, calculations of the foam hydrodynamics • Institute of Modern Physics, Lanzhou, China experimental support (X-ray diagnostics) • Plasma Physics Division GSI project leading, PHELIX-laser, diagnostics, infrastructure EMMI Physics Days 4-5 November 2010 o.rosmej@gsi.de
Last experimental campaign on February-March 2010 EMMI Physics Days 4-5 November 2010 o.rosmej@gsi.de
Conferences and workshops 2010 1. EMMI workshop on Plasma Physics with Intense Heavy Ion and Laser Beams, May 20-21,2010, Moscow, Russia "Experiments on the indirect heating of low Z foam targets" 2. EMMI workshop on “ X-rays as a Tool for Probing Extreme States of Matter” , June 7-9, 2010, GSI-Darmstadt " Properties of combined hohlraum targets for probing with heavy ion beams ” 3. Heavy Ion Fusion Conference (HIF 2010), 31.08-3.09.2010 , Darmstadt,Germany "Properties of combined hohlraum targets for probing with heavy ion beams" 4. 31 th European Conference on Laser Interaction with Matter (ECLIM), September 6-10, 2010 , Budapest, Hungary "Experiments on indirect heating of low density aerogels for applications in heavy ion stopping in plasma" 5. 4 th International conference “Supers strong fields in plasma”, October 3-9, 2010, Varenna, Italy Nanostructures irradiated by fs and ns laser pulses: latest advances on X-ray sources and high energy density plasmas 6. EMMI Physics Days, November 4-5, 2010, GSI-Darmstadt
What we would like to know? 1. Radiation field of the primary hohlraum (converter) 2. Conversion efficiency of the laser energy into soft X- rays 3. Absorption properties of CHO-foams 4. Temperature and ionization degree of heated by X- rays CHO-plasma laser converter X-rays EMMI Physics Days 4-5 November 2010 o.rosmej@gsi.de
X-ray diagnostics set-up X-ray diagnostics are placed in a vacuum chamber U V - f i l m m 1 ~ TGS2 transmission grating spectrometer , range:1.8-20 nm Au-grating 1000/mm PHELIX pin-hole camera Laser 1:2 6cm to UNILAC target 28cm 28cm V m 35cm R c VRD 42cm D 4 1 FSSR1 2 R pin-hole camera S 1:1 S F laser target ~ 1.5m T G S 1 Spatial resolution: pin-holes High resolution transmission grating spectrometers Spectral : FSSR, TGS CCD Au-grating 10000/mm Temporal : X-ray vacuum diodes range: 1- 20nm, abs. calibrated
Front side diagnostics of the converter radiation FSSR (2), mica Target position laser X-ray detector τ ~1ns pin-hole camera with two holes ~ 100 μ m EMMI Physics Days 4-5 November 2010 o.rosmej@gsi.de
Combined targets: converter + foam/foil GSI-converter+foam GSI-converter front-side laser laser 45 (54)° foam back-side converter Au-foil 0.05-0.1 μ m Au10 μ m Sarov-converter TAC( C12H 16 O 8 ) laser cellulose triacetate 3-D regular network with opened cell structure, the most d=1mm fine pores ( ~ 1 μ m) remains stable up to 220C, used at PALS, LIL, GSI diagnostic hole 2mg/cc 800-1000 μ m EMMI Physics Days 4-5 November 2010 o.rosmej@gsi.de
Hohlraum targets after shots Converter, shot 32, E las =228J target front side l a s e HED in the laser focal spot during 1 ns laser pulse r E J ( ) 200 J = = 3 2 MJ mm / ⋅ − 3 2 3 V mm ( ) (0.3 mm ) 10 mm plasma generation target back side After the interaction, at later times, deposited energy is redistributed over the whole hohlraum E J ( ) 200 J = = 3 20 / J mm ~ 0.2 Mbar ⋅ 3 2 ( ) (1.7 ) 1.7 V mm mm mm phase transitions, shock wave generation EMMI Physics Days 4-5 November 2010 o.rosmej@gsi.de
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