Chapter 60 – THE VSANS TECHNIQUE 60:1. MULTIPLE CIRCULAR CONVERGING COLLIMATION 60:3. MULTIPLE SLIT CONVERGING COLLIMATION 60:4. PERFORMANCE OF THE VARIOUS VSANS CONFIGURATIONS 60:4. DISCUSSION
multiple circular source apertures multiple circular sample apertures y z x r1 L1 60:1. MULTIPLE CIRCULAR CONVERGING COLLIMATION
source slits sample slits Dy1 L1 Dx1 60:3. MULTIPLE SLIT CONVERGING COLLIMATION
COMMENTS -- A VSANS instrument is 40 m long. A SANS instrument is 30 m long. -- Qmin for VSANS is one order of magnitude lower than that for SANS. -- Converging collimation lowers the Qmin without large penalty on the flux on sample. Overkill apertures are used to eliminate cross collimation. -- The use of converging lenses increases the flux on sample without penalty on resolution. -- A second high resolution detector is used for the low-Q.