Quartz Cell for a Backscattering Spectrometer

Abstract

We have developed a quartz double cylindrical sample cell optimized for a backscattering neutron spectrometer, especially for BL02 (DNA), MLF in J-PARC. A quartz glass tube, with one end closed, is shaved to obtain a wall thickness of 0.55 mm. The inner tube is properly centered onto a protrusion in the outer tube such that the distance between the outer and inner tubes remains constant. This quartz cell can be used for samples that should not be in contact with the aluminum surface. We verified the cell's background effect between the quartz cell and Al cell by employing QENS measurements using D 2 O buffer. The elastic intensity profiles of the buffer at Q < 1 Å -1 while using both quartz cell and Al cell (A1070) were identical. When Q > 1 Å -1 , however, the profiles were different, which can be attributed to the first sharp diffraction peak of quartz glass. The data should thus be analyzed by consideration of adsorption correction and differences in the individual thickness of the quartz cell for this region.