VLAD has been designed to perform HINS measurements on VESUVIO in the region of the kinematical space (q, ) characterised by 1.5 Å^-1 ≤ q ≤ 10 Å^-1 and 0.3 eV ≤ ≤ 20 eV.
The VLAD equipment on VESUVIO operates in the Resonance Detector (RD) configuration where:

1. An analyser foil strongly absorbs the scattered neutrons over a narrow energy interval through resonance neutron capture;
2. The prompt γ-ray cascade, following the radiative decay of the compound nucleus to the ground state, is detected by a photon detector.

The RD configuration based on YAP scintillators has demonstrated to be effective up to final neutron energies above 100 eV.

On February 2003 the VLAD prototype was installed on the VESUVIO beam line.

The VLAD final design will allow access to lower scattering angles thanks to the new collimation.

Calculations of the resolution components in and q for HINS measurements.

VLAD is Commissioned (November 2005 / February 2006) - PhotoGallery

The prototype VLAD bank consists of a cylindrical aluminum vacuum chamber, connected by a bellow on one side to the VESUVIO sample chamber. On the other side it is connected to the transmission beam tube and has a thin aluminum window (2 mm), enforced by six radial ribs (3 x 25 mm). Next to the vacuum tank a detectors bank covers an angular range between 2° and 5°, with a mean sample-detector distance of about 2.05 m.

Layout of the VESUVIO spectrometer equipped with the VLAD prototype bank: 1= Backward  6Li-glass detectors bank 2= Rotating filter changer, 3= Vacuum tank, 4= Forward  6Li-glass detectors bank, 5= VLAD's vacuum chamber, 6= VLAD bank equipped with YAP scintillators

View of the vacuum chamber and of the detector array containing 4 YAP located at about 2°, 3°, 4° and 5° scattering angles