For Liquid Scintillation Counting Bialkali Photocathode, 51mm (2 Inch) Diameter, 12 Stages, Head-On Type

The R331 and the R331-05 are 51mm (2 Inch) diameter series photomultiplier tubes specifically developed for the liquid scintillation counting. They feature low background noise, high tritium efficiency, good linearity and high gain. The R331 uses a synthetic silica input window and the R331-05 uses a low K content borosilicate glass input window, both with a frosted surface and convex-concave shape. They offer minimized glass scintillations and high collection efficiency.

FEATURES
● Tritium efficiency in tritium window................................ 60% Typ.
● Background noise in tritium window...............16cpm Typ. (R331)
                                                                           18cpm Typ. (R331-05)
● Tritium end point (T.E.P.) voltage.................................. 1700V Typ.
● Dark pulse summation at T.E.P. voltage.............. 3 × 104cpm Max.
● Figure of merit (E2/B).......................................................... 200 Typ.