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Modeling of the electrostatic sheath shape on the rear target surface in short-pulse laser-driven proton acceleration

Published online by Cambridge University Press:  06 March 2006

ERIK BRAMBRINK
Affiliation:
Institute for Nuclear Physics, Darmstadt University Of Technology, Darmstadt, Germany
MARKUS ROTH
Affiliation:
Institute for Nuclear Physics, Darmstadt University Of Technology, Darmstadt, Germany
ABEL BLAZEVIC
Affiliation:
Plasma Physics Department, Gesellschaft für Schwerionenforschung, Darmstadt, Germany
THEODOR SCHLEGEL
Affiliation:
Plasma Physics Department, Gesellschaft für Schwerionenforschung, Darmstadt, Germany

Abstract

Proton beams, generated in the interaction process of short ultra-intense laser pulses with thin foils, carry imprints of rear side target structures. These intensity patterns, imaged with a particle detector, sometimes show slight deformations. We propose an analytical model to describe these deformations by the spatial shape of a monoenergetic layer of protons in the beginning of free proton propagation. We also present results of simulations, which reproduce the detected structures and allow finally making quantitative conclusions on the shape of the layer. In experiments with electrically conducting targets, the shape is always close to a parabolic one independently on target thickness or laser parameters. Since the protons are pulled by the free electrons, there must be a strong correlation to the electron space charge distribution on the rear side of the illuminated foil. Simulations demonstrate that the deformations in the detected patterns of the proton layers are very sensitive to the initial layer shape. Analyzing spatial structures of the generated proton beams we can indirectly conclude on electron transport phenomena in the overdense part of the target.

Type
Research Article
Copyright
© 2006 Cambridge University Press

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References

REFERENCES

Allen, M., Patel, P.K., Mackinnon, A., Price, D., Wilks, S. & Morse, E. (2004). Direct experimental evidence of back-surface ion acceleration from laser-irradiated gold foils. Phys. Rev. Lett. 93, 265004.Google Scholar
Borghesi, M., Campbell, D.H., Schiavi, A., Willi, O., Mackinnon, A.J., Hicks, D., Patel, P., Gizzi, L.A., Galimberti, M. & Clarke, R.J. (2002). Laser-produced protons and their applications as a particle probe. Laser Part. Beams 20, 269.Google Scholar
Borghesi, M., Audebert, P., Bulanov, S.V., Cowan, T., Fuchs, J., Gauthier, J.C., Mackinnon, A.J., Patel, P.K., Pretzler, G., Romagnani, L., Schiavi, A., Toncian, T. & Willi, O. (2005). High-intensity laser-plasma interaction studies employing laser-driven proton probes. Laser Part. Beams 23, 291.Google Scholar
Brambrink, E., Roth, M., Karsch, S., Neely, D., Clarke, R., McKanna, P. & Ledingham, K. (2004). Emittance measurement of energetic proton beams generated with a petawatt laser. CLF Ann. Rep.
Breschi, E., Borghesi, M., Campbell, D.H., Galimberti, M., Giulietti, D., Gizzi, L.A., Romagnani, L., Schiavi, A. & Willi, O. (2004). Spectral and angular characterization of laser-produced proton beams from dosimetric measurements. Laser Part. Beams 22, 393.Google Scholar
Clark, E.L., Krushelnick, K.R. Davies, J., Zepf, M., Tatarakis, M., Beg, F.N., Machacek, A., Norreys, P.A., Santala, M.I.K., Watts, I., &Dangor, A.E. (2000). Measurements of energetic proton transport through magnetized plasma from intense laser interactions with solids. Phys. Rev. Lett. 84, 670.Google Scholar
Cowan, T.E., Fuchs, J., Ruhl, H., Kemp, A., Audebert, P., Roth, M., Stephens, R., Barton, I., Blazevic, A., Brambrink, E., Cobble, J., Fernández, J., Gauthier, J.-C., Geissel, M., Hegelich, M., Kaae, J., Karsch, G.P., Le Sage, S., Letzring, M., Manclossi, S., Meyroneinc, A., Newkirk, S., Pépin, H. & Renard-LeGalloudec N. (2004). Ultralow emittance, multi-MeV proton beams from a laser virtual-cathode plasma accelerator. Phys. Rev. Lett. 92, 204801.Google Scholar
Fernandez, J.C., Hegelich, B.M., Cobble, J.A., Flippo, K.A., Letzring, S.A., Johnson, R.P., Gautier, D.C., Shimada, T., Kyrala, G.A., Wang, Y., Wettland, C.J. & Schreiber, J. (2005). Laser-ablation treatment of short-pulse laser targets: Toward an experimental program on energetic-ion interactions with dense plasmas. Laser Part. Beams 23, 267.Google Scholar
Fuchs, J., Cowan, T.E., Audebert, P., Ruhl, H., Gremillet, L., Kemp, A., Allen, M., Blazevic, A., Gauthier, J.-C., Geissel, M., Hegelich, M., Karsch, S., Parks, P., Roth, M., Sentoku, Y., Stephens, R. & Campbell, E.M. (2003). Spatial uniformity of laser-accelerated ultrahigh-current MeV electron propagation in metals and insulators. Phys. Rev. Lett. 91, 255002.Google Scholar
Hatchett, S.P., Brown, C.G., Cowan, T.E., Henry, E.A., Johnson, J.S., Key M.H., Koch, J.A., Langdon, A.B., Lasinski, B.F., Lee, R.W., Mackinnon, A.J., Pennington, D.M., Perry, M.D., Phillips, T.W., Roth M., Sangster T.C., Singh, M.S., Snavely, R.A., Stoyer, M.A., Wilks, S.C., &Yasuike, K. (2000). Electron, photon, and ion beams from the relativistic interaction of Petawatt laser pulses with solid targets. Phys. Plasma 7, 2076.Google Scholar
Hegelich, M., Karsch, S., Pretzler, G., Habs, D., Witte, K., Guenther, W., Allen, M., Blazevic, A., Fuchs, J., Gauthier, J.C., Geissel, M., Audebert, P., Cowan, T. & Roth, M. (2002). MeV ion jets from short-pulse-laser interaction with thin foils. Phys. Rev. Lett. 89, 085002.Google Scholar
Kaluza, M., Schreiber, J., Santala, M.I.K., Tsakiris, G.D., Eidmann, K., Meyer-ter-Vehn, J. & Witte, K.J. (2004). Influence of the laser prepulse on proton acceleration in thin-foil experiments. Phys. Rev. Lett. 93, 045003.Google Scholar
Krushelnick, K., Clark, E.L., Zepf, M., Davies, J.R., Beg, F.N., Machacek, A., Santala, M.I.K., Tatarakis, M., Watts, I., Norreys, P.A. & Dangor, A.E. (2000). Energetic proton production from relativistic laser interaction with high density plasmas. Phys. Plasma 7, 2055.Google Scholar
Mackinnon, A.J., Sentoku, Y., Patel, P.K., Price, D.W., Hatchett, S., Key, M.H., Andersen, C., Snavely, R. & Freeman, R.R. (2002). Enhancement of proton acceleration by hot-electron recirculation in thin foils irradiated by ultraintense laser pulses. Phys. Rev. Lett. 88, 215006.Google Scholar
Maksimchuk, A., Gu, S., Flippo, K., Umstadter, Bychenkov, D., &xxx, Yu. (2000). Forward ion acceleration in thin films driven by a high-intensity laser. Phys. Rev. Lett. 84, 4108.Google Scholar
McLaughlin, W.L., Chen Yun-Dong, Soares, C.G., Miller, A., Van Dyk, G., &Lewis, D.F. (1991). Densitometry of the response of a new radiochromic film dosimeter to gamma radiation and electron beams. Nucl. Instr. Meth. A 302, 165.Google Scholar
Murakami, Y., Kitagawa, Y., Sentoku, Y., Mori, M., Kodama, R., Tanaka, K.A., Mima, K. & Yamanaka, T. (2001). Observation of proton rear emission and possible gigagauss scale magnetic fields from ultra-intense laser illuminated plastic target. Phys. Plasma 8, 4138.Google Scholar
Roth, M., Blazevic, A., Geissel, M., Schlegel, T., Cowan, T.E., Allen, M., Gauthier, J.-C., Audebert, P., Fuchs, J., Meyer-ter-Vehn, J., Hegelich, M., Karsch, S. & Pukhov, A. (2002a). Energetic ions generated by laser pulses: A detailed study on target properties. PRST-AB 5, 061301.Google Scholar
Roth, M., Allen, M., Audebert, P., Blazevic, A., Brambrink, E., Cowan, T.E., Fuchs, J., Gauthier, J.-C., Geißel, M., Hegelich, M., Karsch, S., Meyer-ter-Vehn, J., Ruhl, H., Schlegel, T. & Stephens, R.B. (2002b). The generation of high-quality, intense ion beams by ultra-intense lasers. Plasma Phys. Contr. Fusion B44, 99.Google Scholar
Roth, M., Brambrink, E., Audebert, M., Blazevic, A., Clarke, R., Cobble, J., Cowan, T.E., Fernandez, J., Fuchs, J., Geissel, M., Habs, D., Hegelich, M., Karsch, S., Ledingham, K., Neely, D., Ruhl, H., Schlegel, T. & Schreiber, J. (2005). Laser accelerated ions and electron transport in ultra-intense laser matter interaction. Laser Part. Beams 23, 95.Google Scholar
Snavely, R.A., Key, M.H., Hatchett, S.P., Cowan, T.E., Roth, M., Phillips, T.W., Stoyer, M.A., Henry, E.A., Sangster, T.C., Singh, M.S., Wilks, S.C., MacKinnon, A., Offenberger, A., Pennington, D.M., Yasuike, K., Langdon, A.B., Lasinski, B.F., Johnson, J., Perry, M.D. & Campbell, E.M. (2000). Intense high-energy proton beams from petawatt-laser irradiation of solids. Phys. Rev. Lett. 85, 2945.Google Scholar
Wilks, S.C., Langdon, A.B., Cowan, T.E., Roth, M., Singh, M., Hatchett, S., Key, M.H., Pennington, D., MacKinnon, A. & Snavely, R.A. (2001). Energetic proton generation in ultra-intense laser–solid interactions. Phys. Plasma 8, 542.Google Scholar