Experimental evaluation of polychromatic neutron diffraction

Thesis: S.B., Massachusetts Institute of Technology, Department of Nuclear Science and Engineering, 2017.

Bibliographic Details
Main Author: Morrell, Jonathan T
Other Authors: David Moncton and Boris Khaykovich.
Format: Thesis
Language:eng
Published: Massachusetts Institute of Technology 2017
Subjects:
Online Access:http://hdl.handle.net/1721.1/112368
_version_ 1811077382336937984
author Morrell, Jonathan T
author2 David Moncton and Boris Khaykovich.
author_facet David Moncton and Boris Khaykovich.
Morrell, Jonathan T
author_sort Morrell, Jonathan T
collection MIT
description Thesis: S.B., Massachusetts Institute of Technology, Department of Nuclear Science and Engineering, 2017.
first_indexed 2024-09-23T10:42:08Z
format Thesis
id mit-1721.1/112368
institution Massachusetts Institute of Technology
language eng
last_indexed 2024-09-23T10:42:08Z
publishDate 2017
publisher Massachusetts Institute of Technology
record_format dspace
spelling mit-1721.1/1123682019-04-10T11:42:42Z Experimental evaluation of polychromatic neutron diffraction Morrell, Jonathan T David Moncton and Boris Khaykovich. Massachusetts Institute of Technology. Department of Nuclear Science and Engineering. Massachusetts Institute of Technology. Department of Nuclear Science and Engineering. Nuclear Science and Engineering. Thesis: S.B., Massachusetts Institute of Technology, Department of Nuclear Science and Engineering, 2017. This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections. Cataloged from student-submitted PDF version of thesis. Includes bibliographical references (pages 57-58). Neutron diffraction is a technique that allows scientists to measure the arrangement and motions of atoms in a crystalline lattice by observing neutrons scattering at angles that are characteristic of the interatomic distances of the crystal. This is useful for studying the response of crystals to stress, irradiation, or for observing their phases. This thesis implements and analyzes a technique known as polychromatic neutron powder diffraction, which has the potential to be used by an instrument to make many simultaneous neutron diffraction measurements. In this experiment, powder diffraction patterns were measured with a diffractometer in polychromatic mode, using both angle-dispersive and wavelength-dispersive scans of a silicon powder. The intensity and resolution of the Bragg peaks with the instrument in this configuration were compared to Bragg peaks measured by the same instrument in a monochromatic configuration. The intensity of the polychromatic mode was only comparable to the monochromatic mode with looser collimation, which had the consequence of increasing the widths of the measured peaks. This resulted in a polychromatic signal intensity that was greater than the monochromatic signal intensity, and a Bragg peak that was wider than the monochromatic Bragg peak. The effects of the collimators and the sample to detector distances were quantified in experiment and in ray-tracing simulations. While both the monochromatic and the polychromatic configurations had similar counting rates in this experiment, they were both limited by the high background due to the open-beam geometry. A successful implementation of a polychromatic instrument would require substantial filtering and shielding to overcome this effect. by Jonathan T. Morrell. S.B. 2017-12-05T16:24:50Z 2017-12-05T16:24:50Z 2017 2017 Thesis http://hdl.handle.net/1721.1/112368 1011352574 eng MIT theses are protected by copyright. They may be viewed, downloaded, or printed from this source but further reproduction or distribution in any format is prohibited without written permission. http://dspace.mit.edu/handle/1721.1/7582 64 pages application/pdf Massachusetts Institute of Technology
spellingShingle Nuclear Science and Engineering.
Morrell, Jonathan T
Experimental evaluation of polychromatic neutron diffraction
title Experimental evaluation of polychromatic neutron diffraction
title_full Experimental evaluation of polychromatic neutron diffraction
title_fullStr Experimental evaluation of polychromatic neutron diffraction
title_full_unstemmed Experimental evaluation of polychromatic neutron diffraction
title_short Experimental evaluation of polychromatic neutron diffraction
title_sort experimental evaluation of polychromatic neutron diffraction
topic Nuclear Science and Engineering.
url http://hdl.handle.net/1721.1/112368
work_keys_str_mv AT morrelljonathant experimentalevaluationofpolychromaticneutrondiffraction