ABSTRACT
Although beamline instrumentation is by nature driven by science, some recent examples serve as reminders that new technologies also enable new science. Indeed, exploiting the full scientific potential of forthcoming new storage rings with unprecedented source characteristics will, in many cases, require the development and implementation of novel instrumentation. In comparison with present synchrotron radiation facilities, the majority of beamlines should reap immediate performance benefits from the improved source emittance, principally through increased flux and/or horizontal beam size reduction at the sample. Instrumentation will have to develop along similar quantitative and qualitative trends. More speculative and more challenging is anticipating instrumentation that will be required by the new science made possible thanks to the unique coherence properties of diffraction-limited storage rings (DLSRs). ESRF has recently carried out a detailed feasibility study for a new ultra-low-emittance 6â GeV hybrid multibend storage ring, identified as ESRF Upgrade Programme Phase II. Although its performance is not expected to be equivalent to a DLSR source, the successful implementation of the ESRF Phase II project has to address scientific instrumentation issues that are also common to DLSRs. This article aims at providing a comprehensive review of some of the challenges encountered by the ESRF, in the context of the preparation of Phase II of its upgrade programme.
ABSTRACT
The automation of beam delivery, sample handling and data analysis, together with increasing photon flux, diminishing focal spot size and the appearance of fast-readout detectors on synchrotron beamlines, have changed the way that many macromolecular crystallography experiments are planned and executed. Screening for the best diffracting crystal, or even the best diffracting part of a selected crystal, has been enabled by the development of microfocus beams, precise goniometers and fast-readout detectors that all require rapid feedback from the initial processing of images in order to be effective. All of these advances require the coupling of data feedback to the experimental control system and depend on immediate online data-analysis results during the experiment. To facilitate this, a Data Analysis WorkBench (DAWB) for the flexible creation of complex automated protocols has been developed. Here, example workflows designed and implemented using DAWB are presented for enhanced multi-step crystal characterizations, experiments involving crystal reorientation with kappa goniometers, crystal-burning experiments for empirically determining the radiation sensitivity of a crystal system and the application of mesh scans to find the best location of a crystal to obtain the highest diffraction quality. Beamline users interact with the prepared workflows through a specific brick within the beamline-control GUI MXCuBE.
