Very Small Angle Neutron Scattering (VSANS)

Instrument description

The second SANS instrument at BER II is dedicated to soft matter research. V16 covers a Q-range from 10-3 nm-1 to 8.5 nm-1. In standard time-of-flight mode an offset of the detector to the instrument axis to extend the Q range will be possible.

The instrument works in the time-of-flight mode with ordinary pinhole collimation and in an optional high resolution mode using multi pinhole grid collimation. The latter mode will allow for gravitational velocity selection and focuses many beams on a high resolution detector, only used for this option.


 Unpolarized small-angle neutron scattering

Selected examples


Instrument layout

 Time-of-flight standard pin-hole with optional VSANS optics and detector

Instrument Data
Neutron guide NL 4C
straight behind bender, SM coated, m=1
cross section 80x80 mm2 with cut-off λ=0.25 nm
Collimation exchangeable pinhole and guide optics on up to 12m length
Monochromator TOF
Wave length 0.25 nm < λ < 1.8 nm
Wave length resolution
Q range 0.02 nm -1 < Q < 8.0 nm -1
Q resolution 5% < ΔQ/Q < 18%, depending on the chopper settings
Detector 2D 3He detector
• 100x100 cm2 area
• physical pitch: 9 mm
Sample-to-detector distance 1.7m up to 11.2m
Polarized neutrons no, but principally possible
Instrument options • Low-Q mode (not offered to users)
Sample environment Hellma cuvettes (120, 404), rheometer, DEGAS cell and balance, battery cell, cryostats and magnets from sample environment group.
Software Caress (control), Evalstat (in-house DAQ), Mantid (data reduction)