Hard X-ray Spectrographs with Resolution Beyond 100 micro-eV

Abstract

Spectrographs take snapshots of photon spectra with array detectors by dispersing photons of different energies into distinct directions and spacial locations. Spectrographs require optics with a large angular dispersion rate as the key component. In visible light optics diffraction gratings are used for this purpose. In the hard x-ray regime, achieving large dispersion rates is a challenge. Here we show that multi-crystal, multi-Bragg-reflection arrangements feature cumulative angular dispersion rates almost two orders of magnitude larger than those attainable with a single Bragg reflection. As a result, the multi-crystal arrangements become potential dispersing elements of hard x-ray spectrographs. The hard x-ray spectrograph principles are demonstrated by imaging a spectrum of photons with a record high resolution of $\Delta E\simeq 90\mu$eV in hard x-ray regime, using multi-crystal optics as dispersing element. The spectrographs can boost research using inelastic ultra-high-resolution x-ray spectroscopies with synchrotrons and seeded XFELs.

References in corpus (2)

• Angular Dispersion and Anomalous Transmission Cast Ultramonochromatic X Rays
• Enhanced X-Ray Angular Dispersion and X-ray Spectrographs with Resolving Power Beyond 10${}^8$

Cited by in corpus (7)

• Novel opportunities for sub-meV inelastic X-ray scattering at high-repetition rate self-seeded X-ray free-electron lasers
• Theory of angular dispersive imaging hard x-ray spectrographs
• Introduction to High-Resolution Inelastic X-Ray Scattering
• Maximizing Spectral Flux from Self-Seeding Hard X-ray FELs
• X-ray echo spectroscopy
• Theory and optical design of x-ray echo spectrometers
• Aberration-free imaging of inelastic scattering spectra with x-ray echo spectrometers