Editing Neutron diffraction (section)

==== Spallation ====
In spallation sources, high-energy protons (on the order of 1 [[Electronvolt|GeV]]) bombard a heavy metal target (e.g., [[uranium]] (U), [[tungsten]] (W), [[tantalum]] (Ta), [[lead]] (Pb), or [[Mercury (element)|mercury]] (Hg)). This interaction causes the nuclei to spit out neutrons. Proton interactions result in around ten to thirty neutrons per event, of which the bulk are known as "evaporation neutrons"(~2 MeV), while a minority are identified as "cascade neutrons" with energies reaching up to the GeV range. Although spallation is a very efficient technique of neutron production, the technique generates high energy particles, therefore requiring shielding for safety.<ref name="Carpenter-2015">{{Cite book |last=Carpenter |first=John M. |title=Elements of slow-neutron scattering: basics, techniques, and applications |date=2015 |publisher=Cambridge University Press |isbn=978-1-139-02931-5 |location=Cambridge}}</ref>
[[File:Three_major_process_for_neutron_production.png|thumb|Illustration of three major fundamental processes generating neutrons for scattering experiments:   Nuclear fission (Top), Spallation (middle),  Low energy reaction (bottom).<ref>{{Cite journal |last=Dronskowski |first=Richard |last2=Brückel |first2=Thomas |last3=Kohlmann |first3=Holger |last4=Avdeev |first4=Maxim |last5=Houben |first5=Andreas |last6=Meven |first6=Martin |last7=Hofmann |first7=Michael |last8=Kamiyama |first8=Takashi |last9=Zobel |first9=Mirijam |last10=Schweika |first10=Werner |last11=Hermann |first11=Raphaël P. |last12=Sano-Furukawa |first12=Asami |date=2024-06-25 |title=Neutron diffraction: a primer |url=https://www.degruyter.com/document/doi/10.1515/zkri-2024-0001/html |journal=Zeitschrift für Kristallographie - Crystalline Materials |language=en |volume=239 |issue=5-6 |pages=139–166 |doi=10.1515/zkri-2024-0001 |issn=2194-4946}}</ref>]]