GENERAL

FEATURES

Parameter

R331-05

R331

Unit

Spectral Response

Wavelength of Maximum Response

Photo-

cathode

Window

Material

Dynode

Direct

Interelectrode

Capacitances

Base

Weight

Suitable Socket

nm

nm

—

mm dia.

—

—

—

—

pF

pF

—

g

—

300 to 650

420

Bialkali

46

Concave-Convex

Linear focused

12

2

2.5

21-pin glass base

151

E678-21A (Supplied)

160 to 650

Synthetic silica

(Frosted)

Material

Minimum Useful Area

Material

Shape

Structure

Number of Stages

Anode to Last Dynode

Anode to All Other

Electrodes

PHOTOMULTIPLIER TUBES

R331, R331-05

Information furnished by HA MAM ATS U is believed to be reliable. However, no responsibility is assumed for possible inaccuracies or omissions. Specifications are

subject to change without notice. No patent rights are granted to any of the circuits described herein.

Subject to local technical requirements and regulations, availability of products included in this promotional material may var y. Please consult with our sales office.

For Liquid Scintillation Counting

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

Figure 1: Typical Spectral Response

TPMHB0505EA

The R331 and the R331-05 are 51mm (2 Inch) diameter series pho-

tomultiplier tubes specifically developed for the liquid scintillation count-

ing. 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 min-

imized glass scintillations and high collection efficiency.

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

Low K content

borosilicate

glass (Frosted)

100

10

1

0.1

0.01

200

400

600

800

WAVELENGTH (nm)

CATHODE

RADIANT

SENSITIVITY

R331-05

R331

QUANTUM

EFFICIENCY