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Role of surface roughness in hard x-ray emission from femtosecond laser produced copper plasmas

P. P. Rajeev·S. Banerjee·A. S. Sandhu·L. C. Tribedi·G. R. Kumar
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Abstract

The hard x-ray emission in the energy range of 30-300 keV from copper plasmas produced by 100 fs, 806 nm laser pulses at intensities in the range of 10$^{15}-10^{16}$ W cm$^{-2}$ is investigated. We demonstrate that surface roughness of the targets overrides the role of polarization state in the coupling of light to the plasma. We further show that surface roughness has a significant role in enhancing the x-ray emission in the above mentioned energy range.

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P. P. Rajeev, S. Banerjee, A. S. Sandhu, L. C. Tribedi, G. R. Kumar. 2002-04-11. Role of surface roughness in hard x-ray emission from femtosecond laser produced copper plasmas. https://doi.org/10.1103/physreva.65.052903

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