HAMAMATSU R8486, R8487 Datasheet

PHOTOMULTIPLIER TUBES

PRELIMINARY DATA

FEB. 2001

R8486, R8487

For Vacuum Ultraviolet Light Detection

Cs-Te (R8486), Cs-I (R8487) Photocathode, MgF

28 mm (1-1/8 Inch) Diameter, 9-stage, Side-on Type

FEATURES

Sensitivity in the Vacuum Ultraviolet Region

R8486.............................................................115 to 320 nm

R8487.............................................................115 to 195 nm

High Quantum Efficiency (at 121.6 nm)

R8486...............................................................22.5 % (Typ.)

R8487...............................................................26.0 % (Typ.)

High Anode Sensitivity

R8486 (at 254 nm)................................5.2 × 10

R8487 (at 121.6 nm).............................1.0 × 10

5

A/W (Typ.)

5

A/W (Typ.)

2 Window,

APPLICATIONS

Emission Spectroscopy, etc.

GENERAL

Parameter R8486 Unit

Spectral Response
Wavelength
of Maximum Response
Photocathode Material
Window Material
Minimum Effective Area

Structure

Dynode

Direct
Interelectrode
Capacitances
Base
Weight
Suitable Socket for Base (option)

Number of Stage
Material
Anode to Dynode No.9
Anode to
All Other Electrodes

R8487

115 to 320

200

Cs-Te

115 to 195

2

MgF

130

Cs-I

8 × 12

Circular-cage

9

Sb-Cs

Approx. 4
Approx. 6

11-pin base JEDEC No. B11-88

45

E678-11A

nm
nm

—
—

mm

—
—
—

pF
pF

—

g

—

Figure 1: Typical Spectral Response

TPMSB0199EA

100

10

1

QUANTUM
EFFICIENCY

R8486

R8487

QUANTUM EFFICIENCY (%)

0.1

PHOTOCATHODE RADIANT SENSITIVITY (mA/W)

0.01
100

200

PMSF0093

CATHODE
RADIANT
SENSITIVITY

300

WAVELENGTH (nm)

Subject to local technical requirements and regulat ions, availability of products included in this promotional material may var y. P lease consult with our sales office.
Information furnished by HAMA M ATSU is believed to be reliable. However, n o 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.

2001 Hamamatsu Photonics K.K.

©

PHOTOMULTIPLIER TUBES R8486, R8487

MAXIMUM RATINGS (Absolute Maximum Values)

Parameter

Supply Voltage
Between Anode and Cathode
Between Anode and Last Dynode
Between Successive Dynodes
Between First Dynode and Cathode

A

Average Anode Current
Ambient Temperature

CHARACTERISTICS (at 25 °C)

Parameter R8487R8486 Unit

Cathode Sensitivity
Quantum Efficiency at 121 nm
at 254 nm
Anode Sensitivity
Radiant at 121 nm
at 254 nm
Gain
Anode Dark Current (After 30 minute storage in darkness)
ENI (Equivalent Noise Input) D at 121 nm
at 254 nm
Time Response
Anode Pulse Rise Time
Electron Transit Time
Transit Time Spread

B

E

F

G

Rating Unit

1250

250
250
250

0.1

-30 to +50

C

V dc
V dc
V dc
V dc
V dc

°C

22.5

25.0

—

5.2 × 10

1.0 × 10

1.0
—

1.09 × 10

2.2
22

1.2

5
7

-16

26.0
—

1.0 × 10
—

3.9 × 10

0.1

1.12 × 10
—

2.2
22

1.2

5

6

-16

%
%

A/W
A/W

—

nA

W
W

ns
ns
ns

NOTES

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

Electrode
Distribution

Ratio
Supply Voltage=1000 V dc
K: Cathode Dy: Dynode P: Anode

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 uni­ty in the output of a photomultiplier tube.

ENI =

where q =







K Dy1 Dy2 Dy3 Dy4 Dy5 Dy6 Dy7 Dy8 Dy9 P

1111111111

2q·ldb·G·∆f

s

Electronic charge (1.60 × 10
Anode dark current(after 30 minutes storage) in amperes.

ldb =

Gain.

G =

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

∆f =

Anode radiant sensitivity in amperes per watt at the

S =

-19

coulomb).

wavelength of peak response.

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.