Fig. 8
From: Sample changers for direct geometry neutron chopper spectrometers
Method to determine sample position on the SEQUOIA 3-sample changer. (a) SEQUOIA detector array illustrating detector counts as a function of position on the array. The detector array is viewed from the sample position of the instrument. The white box in the center of the figure is the beam stop of the instrument. The lighter shaded annular region corresponds to a region of interest set to integrate the detected neutrons for the first two Bragg peaks of an empty aluminum sample can. The bright spot to the left of the beam stop is due to masking a significant portion of the right side of the incident beam on the sample as described in the text. (b) Integrated scattering intensity normalized to proton charge as a function of sample rotation angle and integrated over the region of interest shown in panel (a). Inset depicts the geometry of incident beam and sample rotation described in the text to determine the sample positions for the SEQUOIA 3-sample changer.
