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A small and robust active beamstop for scattering experiments on high-brilliance undulator beamlines.

ABSTRACT: A small active in-vacuum beamstop has been developed to monitor the flux of intense third-generation synchrotron X-ray beams protecting the downstream detector from the direct beam. Standard active beamstops, where a built-in diode directly absorbs the beam, have limitations in size and lifetime. In the present design, a silicon PIN diode detects the photons back-scattered from a cavity in the beamstop. This approach drastically reduces the radiation dose on the diode and thus increases its lifetime. The beamstop with a diameter of 2?mm has been fabricated to meet the requirements for the P12 bioSAXS beamline of EMBL Hamburg at PETRA?III (DESY). The beamstop is in regular user operation at the beamline and displays a good response over the range of energies tested (6-20?keV). Further miniaturization of the diode is easily possible as its size is not limited by the PIN diode used.

SUBMITTER: Blanchet CE

PROVIDER: S-EPMC4344362 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature

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A small and robust active beamstop for scattering experiments on high-brilliance undulator beamlines.

Blanchet Clement E CE Hermes Christoph C Svergun Dmitri I DI Fiedler Stefan S

Journal of synchrotron radiation 20150204 2

A small active in-vacuum beamstop has been developed to monitor the flux of intense third-generation synchrotron X-ray beams protecting the downstream detector from the direct beam. Standard active beamstops, where a built-in diode directly absorbs the beam, have limitations in size and lifetime. In the present design, a silicon PIN diode detects the photons back-scattered from a cavity in the beamstop. This approach drastically reduces the radiation dose on the diode and thus increases its life ...[more]

PMID: 25723949

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