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Title: Study of Boron and Molybdenum Plasmas on Multipulse Interaction of Femtosecond Radiation with a Target

Abstract

Laser plasmas generated by femtosecond radiation on the surface of boron and molybdenum targets are investigated by the shadowgraph method. The modes of single-pulse and multipulse interaction of laser radiation with a target are compared. The occurrence of plasma bullets is discussed, which were observed on both single-pulse and multipulse interaction with the same area of a target. The wavefront velocities of expanding boron and molybdenum plasmas were measured to be 5 x 10{sup 4} and 6 x 10{sup 3} m s{sup -1}, respectively. The electron density measured by interferometry using a time delay of 800 ps in a boron plasma excited by 795-nm radiation with an intensity of 10{sup 16} W cm{sup -2} amounted to 8 x 10{sup 19} cm{sup -3}. The correlation between some specific features of the plasma and the generation of the 3/2 harmonic, observed on multipulse interaction of femtosecond radiation with a boron target, is discussed.

Authors:
 [1];  [2]; ; ;  [1]
  1. Institute for Solid State Physics, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8581 (Japan)
  2. (Uzbekistan)
Publication Date:
OSTI Identifier:
20723275
Resource Type:
Journal Article
Resource Relation:
Journal Name: Optics and Spectroscopy; Journal Volume: 99; Journal Issue: 6; Other Information: Translated from Optika i Spektroskopiya , ISSN 0030-4034, 99, 1039-1044 (No. 6, 2005); DOI: 10.1134/1.2149426; (c) 2005 Pleiades Publishing, Inc; Country of input: International Atomic Energy Agency (IAEA); TN:
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; BORON; CORRELATIONS; ELECTRON DENSITY; INTERACTIONS; INTERFEROMETRY; LASER RADIATION; LASERS; MOLYBDENUM; NONLINEAR PROBLEMS; PLASMA; PLASMA DENSITY; PLASMA DIAGNOSTICS; PLASMA PRODUCTION; PULSES; TIME DELAY; VISIBLE RADIATION

Citation Formats

Ganeev, R.A., NPO Akadempribor, Akademgorodok, Tashkent, 700125, Suzuki, M., Baba, M., and Kuroda, H.. Study of Boron and Molybdenum Plasmas on Multipulse Interaction of Femtosecond Radiation with a Target. United States: N. p., 2005. Web. doi:10.1134/1.2149426.
Ganeev, R.A., NPO Akadempribor, Akademgorodok, Tashkent, 700125, Suzuki, M., Baba, M., & Kuroda, H.. Study of Boron and Molybdenum Plasmas on Multipulse Interaction of Femtosecond Radiation with a Target. United States. doi:10.1134/1.2149426.
Ganeev, R.A., NPO Akadempribor, Akademgorodok, Tashkent, 700125, Suzuki, M., Baba, M., and Kuroda, H.. Thu . "Study of Boron and Molybdenum Plasmas on Multipulse Interaction of Femtosecond Radiation with a Target". United States. doi:10.1134/1.2149426.
@article{osti_20723275,
title = {Study of Boron and Molybdenum Plasmas on Multipulse Interaction of Femtosecond Radiation with a Target},
author = {Ganeev, R.A. and NPO Akadempribor, Akademgorodok, Tashkent, 700125 and Suzuki, M. and Baba, M. and Kuroda, H.},
abstractNote = {Laser plasmas generated by femtosecond radiation on the surface of boron and molybdenum targets are investigated by the shadowgraph method. The modes of single-pulse and multipulse interaction of laser radiation with a target are compared. The occurrence of plasma bullets is discussed, which were observed on both single-pulse and multipulse interaction with the same area of a target. The wavefront velocities of expanding boron and molybdenum plasmas were measured to be 5 x 10{sup 4} and 6 x 10{sup 3} m s{sup -1}, respectively. The electron density measured by interferometry using a time delay of 800 ps in a boron plasma excited by 795-nm radiation with an intensity of 10{sup 16} W cm{sup -2} amounted to 8 x 10{sup 19} cm{sup -3}. The correlation between some specific features of the plasma and the generation of the 3/2 harmonic, observed on multipulse interaction of femtosecond radiation with a boron target, is discussed.},
doi = {10.1134/1.2149426},
journal = {Optics and Spectroscopy},
number = 6,
volume = 99,
place = {United States},
year = {Thu Dec 15 00:00:00 EST 2005},
month = {Thu Dec 15 00:00:00 EST 2005}
}
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  • Hard x-ray spectra (10{endash}100 keV) created in high contrast, 400 fs, laser pulse interaction with solid targets, have been studied for laser intensities in the 10{sup 17}{endash}10{sup 19}&hthinsp;W/cm{sup 2} range. The target atomic numbers ({ital Z}) extended from Z=13 to Z=73. The measured conversion efficiency at Ag K{sub {alpha}} emission line was 10{sup {minus}3}{percent} at 5{times}10{sup 18}&hthinsp;W/cm{sup 2}. It has been confirmed that the hot electron temperature increased as (I{lambda}{sup 2}){sup 1/3} and the fraction of laser energy in hot electrons follows scaling law of (I{lambda}{sup 2}){sup 3/4}. {copyright} {ital 1999 American Institute of Physics.}