Target-heating effects on the Kα1,2-emission spectrum from solid targets heated by laser-generated hot electrons

Target-heating effects on the Kα1,2-emission spectrum from small-mass Cu targets irradiated with 1-ps pulses focused to intensities >1018 W/cm2 have been observed. A collisional-radiative atomic physics model is unable to reproduce the time-integrated Kα1,2-emission spectrum from the smallest-mass targets when calculated with a single, time-independent thermal-electron temperature. When time-dependent heating to several hundred electron volts is included in the model, the synthetic spectra better reproduce the main observed spectral features.

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