title: An improved method for calibrating time-of-flight Laue single-crystal neutron diffractometers.
abstract: A robust and comprehensive method for determining the orientation matrix of a single-crystal sample using the neutron Laue time-of-flight (TOF) technique is described. The new method enables the measurement of the unit-cell parameters with an uncertainty in the range 0.015-0.06%, depending upon the crystal symmetry and the number of reflections measured. The improved technique also facilitates the location and integration of weak reflections, which are often more difficult to discern amongst the increased background at higher energies. The technique uses a mathematical model of the relative positions of all the detector pixels of the instrument, together with a methodology that establishes a reproducible reference frame and a method for determining the parameters of the instrument detector model. Since all neutron TOF instruments require precise detector calibration for their effective use, it is possible that the method described here may be of use on other instruments where the detector calibration cannot be determined by other means.
authors.affiliation: ISIS Facility, STFC Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Chilton, Didcot, Oxfordshire OX11 OQX, England ; SUPA, School of Physics and Astronomy and Centre for Science at Extreme Conditions, University of Edinburgh, Mayfield Road, Edinburgh EH9 3JZ, Scotland.
authors.forename: Craig L
authors.initials: CL
authors.lastname: Bull
authors.affiliation: ISIS Facility, STFC Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Chilton, Didcot, Oxfordshire OX11 OQX, England ; SUPA, School of Physics and Astronomy and Centre for Science at Extreme Conditions, University of Edinburgh, Mayfield Road, Edinburgh EH9 3JZ, Scotland.
authors.forename: Michael W
authors.initials: MW
authors.lastname: Johnson
authors.affiliation: SUPA, School of Physics and Astronomy and Centre for Science at Extreme Conditions, University of Edinburgh, Mayfield Road, Edinburgh EH9 3JZ, Scotland.
authors.forename: Hayrullo
authors.initials: H
authors.lastname: Hamidov
authors.affiliation: SUPA, School of Physics and Astronomy and Centre for Science at Extreme Conditions, University of Edinburgh, Mayfield Road, Edinburgh EH9 3JZ, Scotland.
authors.forename: Kazuki
authors.initials: K
authors.lastname: Komatsu
authors.affiliation: SUPA, School of Physics and Astronomy and Centre for Science at Extreme Conditions, University of Edinburgh, Mayfield Road, Edinburgh EH9 3JZ, Scotland.
authors.forename: Malcolm
authors.initials: M
authors.lastname: Guthrie
authors.affiliation: ISIS Facility, STFC Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Chilton, Didcot, Oxfordshire OX11 OQX, England.
authors.forename: Matthias J
authors.initials: MJ
authors.lastname: Gutmann
authors.affiliation: SUPA, School of Physics and Astronomy and Centre for Science at Extreme Conditions, University of Edinburgh, Mayfield Road, Edinburgh EH9 3JZ, Scotland.
authors.forename: John S
authors.initials: JS
authors.lastname: Loveday
authors.affiliation: SUPA, School of Physics and Astronomy and Centre for Science at Extreme Conditions, University of Edinburgh, Mayfield Road, Edinburgh EH9 3JZ, Scotland.
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Nelmes
keywords: calibration; neutron diffraction; neutron instruments; time-of-flight