Open AccessX‐rays only when you want them: optimized pump–probe experiments using pseudo‐single‐bunch operation
Author(s) -
Hertlein M. P.,
Scholl A.,
Cordones A. A.,
Lee J. H.,
Engelhorn K.,
Glover T. E.,
Barbrel B.,
Sun C.,
Steier C.,
Portmann G.,
Robin D. S.
Publication year - 2015
Publication title -
journal of synchrotron radiation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.172
H-Index - 99
ISSN - 1600-5775
DOI - 10.1107/s1600577515001770
Subject(s) - picosecond , streak camera , optics , laser , detector , signal (programming language) , physics , noise (video) , excitation , materials science , computer science , image (mathematics) , programming language , quantum mechanics , artificial intelligence
Laser pump–X‐ray probe experiments require control over the X‐ray pulse pattern and timing. Here, the first use of pseudo‐single‐bunch mode at the Advanced Light Source in picosecond time‐resolved X‐ray absorption experiments on solutions and solids is reported. In this mode the X‐ray repetition rate is fully adjustable from single shot to 500 kHz, allowing it to be matched to typical laser excitation pulse rates. Suppressing undesired X‐ray pulses considerably reduces detector noise and improves signal to noise in time‐resolved experiments. In addition, dose‐induced sample damage is considerably reduced, easing experimental setup and allowing the investigation of less robust samples. Single‐shot X‐ray exposures of a streak camera detector using a conventional non‐gated charge‐coupled device (CCD) camera are also demonstrated.