A neutron-velocity selector is a device that allows
neutron
The neutron is a subatomic particle, symbol or , which has a neutral (not positive or negative) charge, and a mass slightly greater than that of a proton. Protons and neutrons constitute the nuclei of atoms. Since protons and neutrons beh ...
s of defined velocity to pass while absorbing all other neutrons, to produce a monochromatic neutron beam.
[
] It has the appearance of a many-bladed turbine. The blades are coated with a strongly neutron-absorbing material, such as
Boron-10
Boron is a chemical element with the symbol B and atomic number 5. In its crystalline form it is a brittle, dark, lustrous metalloid; in its amorphous form it is a brown powder. As the lightest element of the ''boron group'' it has thr ...
.
Neutron-velocity selectors are commonly used in neutron research facility to produce a monochromatic beam of neutrons. Due to physical limitations of materials and motors, limiting the maximum speed of rotation of the blades, these devices are only useful for relatively
slow neutron
The neutron detection temperature, also called the neutron energy, indicates a free neutron's kinetic energy, usually given in electron volts. The term ''temperature'' is used, since hot, thermal and cold neutrons are moderated in a medium with ...
s.
References
External links
A commercially available neutron velocity selector for neutron research({{webarchive
, url=https://web.archive.org/web/20120302004630/http://speed.sii.co.jp/data/file_PRODUCT_MASTER_1381_GRAPHIC02.pdf
, date=2 March 2012
)
Biological techniques and tools
Neutron-related techniques