writer：Taisen Zuo; He Cheng;* Yuanbo Chen; Fangwei Wang
keywords：very small angle neutron scattering, china spallation neutron source
source：期刊
specific source：Chinese Physics C
Issue time：2016年

Very Small Angle Neutron Scattering (VSANS) is an upgrade of the traditional Small Angle Neutron

Scattering (SANS) technique which can cover three orders of magnitude of length scale from one nanometer to one

micrometer. It is a powerful tool for structure calibration in polymer science, biology, material science and condensed

matter physics. Since the rst VSANS instrument, D11 in Grenoble, was built in 1972, new collimation techniques,

focusing optics (multi-beam converging apertures, material or magnetic lenses, and focusing mirrors) and higher

resolution detectors combined with the long

ight paths and long incident neutron wavelengths have been developed.

In this paper, a detailed review is given of the development, principles and application conditions of various VSANS

techniques. Then, beam current gain factors are calculated to evaluate those techniques. A VSANS design for the

China Spallation Neutron Source (CSNS) is thereby presented.