PHOTOMULTIPLIER TUBES R8486, R8487

MAXIMUM RATINGS (Absolute Maximum Values)

NOTES

CHARACTERISTICS (at 25

°C)

Parameter

Parameter

R8487

R8486

Unit

Rating

Unit

V dc

V dc

V dc

V dc

V dc

°C

1250

250

250

250

0.1

-30 to +50

22.5

25.0

—

5.2

1.0

1.0

—

1.09

2.2

22

1.2

26.0

—

1.0

—

3.9

0.1

1.12

—

2.2

22

1.2

%

%

A/W

A/W

—

nA

W

W

ns

ns

ns

Supply Voltage

Between Anode and Cathode

Between Anode and Last Dynode

Between Successive Dynodes

Between First Dynode and Cathode

Ambient Temperature

Cathode Sensitivity

Quantum Efficiency at 121 nm

at 254 nm

Radiant at 121 nm

at 254 nm

Gain

at 254 nm

Time Response

A: Averaged over any interval of 30 seconds maximum.

B: Measured with the same light source as Note B and with the voltage

distribution ratio shown in Table 1 below.

Table 1: Voltage Distribution Ratio

C: Measured with the same supply voltage and voltage distribution ratio

as Note E after removal of light.

D: ENI is an indication of the photon-limited signal-to-noise ratio. It refers

to the amount of light in watts to produce a signal-to-noise ratio of uni-

ty in the output of a photomultiplier tube.

ENI =

E: The rise time is the time for the output pulse to rise from 10 % to 90 %

of the peak amplitude when the entire photocathode is illuminated by a

delta function light pulse.

F: The electron transit time is the interval between the arrival of delta func-

tion light pulse at the entrance window of the tube and the time when

the anode output reaches the peak amplitude. In measurement, the

whole photocathode is illuminated.

G: Also called transit time jitter. This is the fluctuation in electron transit

time between individual pulses in the signal photoelectron mode, and

may be defined as the FWHM of the frequency distribution of electron

transit times.

Electrode

Distribution

Ratio

K Dy1 Dy2 Dy3 Dy4 Dy5 Dy6 Dy7 Dy8 Dy9

P

111111111

1

Supply Voltage=1000 V dc

K: Cathode

Dy: Dynode

P: Anode

s

2q·ldb·G·

∆f

Electronic charge (1.60

Anode dark current(after 30 minutes storage) in amperes.

Gain.

Bandwidth of the system in hertz. 1 hertz is used.

Anode radiant sensitivity in amperes per watt at the

wavelength of peak response.

where

q =

ldb =

G =

∆f =

S =