High-performance, short solid state collimators with reflecting walls

We report about the first experimental test of neutron solid state collimators with reflecting walls. Si wafers are the collimator channel coated on both sides with a reflecting layer covered by an absorbing Gd layer. The collimators produce a beam with quasi-rectangular distribution of angles, which represents an intensity gain at equal resolution compared to the triangular distribution in conventional Soller collimators. These compact collimators can provide for high angular resolution with good transmission in very limited space.