Development and calibration of a Thomson parabola with microchannel plate for the detection of laser-accelerated MeV ions.

This article reports on the development and application of a Thomson parabola (TP) equipped with a (90x70) mm(2) microchannel-plate (MCP) for the analysis of laser-accelerated ions, produced by a high-energy, high-intensity laser system. The MCP allows an online measurement of the produced ions in every single laser shot. An electromagnet instead of permanent magnets is used that allows the tuning of the magnetic field to adapt the field strength to the analyzed ion species and energy. We describe recent experiments at the 100 TW laser facility at the Laboratoire d'Utilization des Lasers Intenses (LULI) in Palaiseau, France, where we have observed multiple ion species and charge states with ions accelerated up to 5 MeV/u (O(+6)), emitted from the rear surface of a laser-irradiated 50 microm Au foil. Within the experiment the TP was calibrated for protons and for the first time conversion efficiencies of MeV protons (2-13 MeV) to primary electrons (electrons immediately generated by an ion impact onto a surface) in the MCP are presented.

[1]  E. Jones,et al.  Ion‐expansion energy spectra correlated to laser plasma parameters , 1973 .

[2]  S. Wilks,et al.  Direct experimental evidence of back-surface ion acceleration from laser-irradiated gold foils. , 2004, Physical review letters.

[3]  Michael D. Perry,et al.  Electron, photon, and ion beams from the relativistic interaction of Petawatt laser pulses with solid targets , 2000 .

[4]  S Meyroneinc,et al.  Ultralow emittance, multi-MeV proton beams from a laser virtual-cathode plasma accelerator. , 2004, Physical review letters.

[5]  Deanna M. Pennington,et al.  Energetic proton generation in ultra-intense laser–solid interactions , 2000 .

[6]  Samuel A. Letzring,et al.  Ablation cleaning techniques for high-power short-pulse laser produced heavy ion targets , 2006, SPIE High-Power Laser Ablation.

[7]  G. Malka,et al.  FAST NEUTRON EMISSION FROM A HIGH-ENERGY ION BEAM PRODUCED BY A HIGH-INTENSITY SUBPICOSECOND LASER PULSE , 1999 .

[8]  K. Witte,et al.  Source-size measurements and charge distributions of ions accelerated from thin foils irradiated by high-intensity laser pulses , 2004 .

[9]  P. Audebert,et al.  Laser-driven proton scaling laws and new paths towards energy increase , 2006 .

[10]  T. C. Sangster,et al.  Intense high-energy proton beams from Petawatt-laser irradiation of solids. , 2000, Physical review letters.

[11]  Miquel,et al.  Experimental Confirmation of Ponderomotive-Force Electrons Produced by an Ultrarelativistic Laser Pulse on a Solid Target. , 1996, Physical review letters.

[12]  S. J. Thomson,et al.  XXVI. Rays of positive electricity , 1907 .

[13]  Gerard Mourou,et al.  Compression of amplified chirped optical pulses , 1985 .

[14]  J. Wiza.  Microchannel plate detectors , 1979 .

[15]  K. Witte,et al.  MeV ion jets from short-pulse-laser interaction with thin foils. , 2002, Physical review letters.

[16]  K. Flippo,et al.  Laser acceleration of quasi-monoenergetic MeV ion beams , 2006, Nature.

[17]  T. C. Sangster,et al.  Intense electron and proton beams from PetaWatt laser–matter interactions , 2000 .

[18]  T E Cowan,et al.  Study of saturation of CR39 nuclear track detectors at high ion fluence and of associated artifact patterns. , 2007, The Review of scientific instruments.

[19]  P. Mora,et al.  Plasma expansion into a vacuum. , 2003, Physical review letters.

[20]  B. Sharkov,et al.  Laser detector for accelerators of heavy multiply charged ions , 1989 .

[21]  R R Freeman,et al.  Use of GafChromic film to diagnose laser generated proton beams. , 2008, The Review of scientific instruments.

[22]  owski,et al.  Thomson parabola ion spectrograph with the microchannel plate image converter in investigations of high-Z laser plasma ion sources , 1996 .

[23]  Gerard Mourou,et al.  Generation and characterization of the highest laser intensities (1022 W/cm2) , 2004, CLEO 2004.

[24]  A. P. Fews,et al.  Fully automated image analysis of etched tracks in CR-39 , 1992 .

[25]  J. Meyer-ter-Vehn,et al.  Neutron production by 200 mJ ultrashort laser pulses , 1998 .

[26]  K. Witte,et al.  MeV γ-ray yield from solid targets irradiated with fs-laser pulses , 1998 .

[27]  K.-U. Amthor,et al.  Laser-plasma acceleration of quasi-monoenergetic protons from microstructured targets , 2006, Nature.

[28]  M. Geissel,et al.  Laser beam-profile impression and target thickness impact on laser-accelerated protons , 2008 .

[29]  T. C. Sangster,et al.  Hot electron production and heating by hot electrons in fast ignitor research , 1998 .

[30]  E. Brambrink,et al.  Transverse characteristics of short-pulse laser-produced ion beams: a study of the acceleration dynamics. , 2006, Physical review letters.