Open AccessHigh-resolution stigmatic spectrograph for a wavelength range of 125–30 nm
Author(s) -
A. N. Shatokhin,
A. O. Kolesnikov,
P. V. Sasorov,
E. A. Vishnyakov,
Е. Н. Рагозин
Publication year - 2018
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.26.019009
Subject(s) - optics , extreme ultraviolet , spectrograph , physics , spectral resolution , grating , wavelength , monochromator , plasma diagnostics , laser , plasma , spectral line , quantum mechanics , astronomy
We describe a broadband (12.5-30 nm) extreme ultraviolet (XUV) spectrograph, which is stigmatic throughout its operating range. The instrument employs a near-normal-incidence aperiodic Mo/Si multilayer mirror and a grazing-incidence plane varied line-space (VLS) grating. Strict stigmatism is fulfilled simultaneously at two wavelengths and the condition of practical stigmatism is fulfilled over two octaves in wavelength. The vertically space-resolved line spectra of multiple charge ions from laser plasma were recorded to demonstrate a spectral resolving power of 10 3 and a spatial resolution of ~26 μm, both figures corresponding to two detector pixels. The electron density was evaluated from the Stark broadening of the Balmer line Hβ (135 Å) of C VI in the plasma excited by 0.5 J, 8 ns, 1.06 μm pulses.