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Monoenergetic proton radiography of laser-plasma interactions and capsule implosions. Protons per unit area on detector. Imploding cone-in-shell capsule. 2.7 mm. 15-MeV proton backlighter (imploded D 3 He-filled capsule). Imaging detector. FSC annual meeting Chicago, Feb 28, 2007.
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Monoenergetic proton radiography of laser-plasma interactions and capsule implosions Protons per unit area on detector Imploding cone-in-shell capsule 2.7 mm 15-MeV proton backlighter (imploded D3He-filled capsule) Imaging detector FSC annual meeting Chicago, Feb 28, 2007 C. K. Li & R. D. Petrasso MIT
Collaborators R. Betti J. P. Knauer D. D. Meyerhofer W. Theobald LLE J. A. Frenje C. K. Li* R. D. Petrasso J. R. Rygg* F. H. Séguin MIT * PI of Feb. 14 experiments
Summary: Compelling radiographic data were obtained in 14 Feb. 2007 FSC experiments • Monoenergetic proton radiography • February 14 experiments with • laser-plasma interactions and capsule implosions • Excellent data obtained • Processing & analysis are underway • Future work
A monoenergetic backlighter in the form of a capsule implosion has unique features Subject: implosion or laser-foil interaction Backlighter Implosion Monoenergetic proton spectrum B Laser Ep CR-39 Detector • Monoenergetic – quantitative results • ► from trajectory displacements (due to fields) • ►from energy loss (due to slowing in matter) • Isotropic – wide field of view • –multiple experiments simultaneously at different angles • Different particles can be used for different experiments
CR-39 detectors can be configured to match particle CR-39 (1000-µm-thick) Backlighter capsule Object imaged Filters For the Feb 14 experiments, only a fraction of the back pieces of CR-39 have been processed
Monoenergetic protons can be divided into beamlets for deflectometry of magnetic fields mesh protons Simulation of magnetic bubble Image data Li et al. , PRL 2006
T3He D ( 100) DDp D3He p (x100) DT a Different charged, monoenergetic particles can be matched to the fields and ρR of an HED experiment OMEGA shot 14972 ρR : ~ 5 to ~ 300 mg/cm2 rgyro: differ by ~ X 5 Séguin et al., RSI 2003
FSC radiography experiments – February 14, 2007 • Experiments 1-3: B fields • Laser-plasma interactions • Effects of Au boundary • Experiments 4-6: Fields and ρL in capsule implosions • Cone-in-shell capsules • Spherical capsules
Experiments 1-3: B fields laser-plasma interactions & effects of Au boundary CH foil CH foil 6-beam ring Ni mesh CH foil 6-beam ring Au tube back-side beam front- side beam (1)* 6-beam ring (2)* 6-beam ring with Au tube (3) beams on front and back * Preliminary data shown here
Experiments 4-6: Fields and ρL in capsule implosions cone-in-shell capsules & spherical capsules (4)* Cone-in-shell capsule (5) Spherical capsule, symmetric drive (6) Spherical capsule, asymmetric drive * Preliminary data shown here
Multiple experiments were performed simultaneously, taking advantage of the isotropic backlighter Backlighter Capsule TCC TIM6 Object Foil Cone TIM3 Au Tube
Experiments 1 & 2:B fields generated by a ring of beams on a CH foil, with and without an Au tube Protons Au CH Side view Top view
Experiments 1 & 2:Preliminary data Time 0 ns 0.5 ns 1.5 ns With Au tube Without Au tube 5 mm
Experiment 4:First observation of rippled field structure outside an imploding capsule! Protons per unit area on detector Imploding cone-in-shell capsule 2.7 mm 15-MeV proton backlighter Imaging detector
Experiment 4:Preliminary data Visible light photograph Protonenergy image (darker means lower energy, higher ∫ ρ dl ) Proton fluence image (darker means more protons) Before implosion: Time During implosion (1.5 ns): 2.7 mm
Work required to finish study of February 14, 2007 data • Process remaining detector data • Analyze B fields and ρL in implosions • Cone-in-shell capsules • Spherical capsules with symmetric drive • Spherical capsules with asymmetric drive • Analyze B fields due to 6 laser beams on CH foil • Without Au tube • With Au tube • Analyze B fields in front- & back-side laser-plasma interactions • Submit scientific papers and report on these efforts.
Where we’re going • Develop new radiography analysis methods • Develop improved radiography detector methods • Pursue experiments in fuel assembly: • ρR, ρR asymmetries, fields, fusion burn images • Request 2 shot days in next year
New detector configurations with stacks of thin CR-39 will be developed 500-µm-thick CR-39 Signals on all surfaces
8x106 Yield / MeV 0 10 MeV 15 Mass assembly for Fast Ignition will be studied by combining proton spectrometry and radiography C. Stoeckl, et al., Plasma Phys. and Control. Fusion (2005)
Summary: Compelling radiographic data were obtained in 14 Feb. 2007 FSC experiments • Monoenergetic proton radiography • February 14 experiments with • laser-plasma interactions and capsule implosions • Excellent data obtained • Processing & analysis are underway • Future work