DiProI Beamline Description 2015

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Kirkpatrick-Baez (KB) focusing mirrors

The FEL beam is focused on the sample of the DiProI experimental station by a set of two bendable planar-elliptical mirrors in Kirkpatrick-Baez (KB) configuration. A focal spot smaller than 10 x 10 μm2 have been achieved with wavelengths between 50 nm and 20 nm.
An improvement of the bending system is expected to bring the focus size down to 3 x 5 μm2 (slope error 0.5 μrad), providing a flux of 1016 W/cm2 on the sample, for 100 fs pulses of 1012 photons at 5 nm wavelength. 		Layout of the focusing optics

Focus size and shape

Indentation on PMMA produced by the focused beam Size and shape of the focus can be reconstructed by a wave front sensor and measured making indentations impinging with the FEL beam on a PMMA film. Wave front sensor reconstruction and optical microscope analysis confirmed that the current system provides a spot smaller than 10 x 10 μm2.
Last Updated on Monday, 28 December 2015 20:51