SEM-6 channel-type secondary electron multiplier with electrostatic electron focusing and open input is intended for the detection of charged and neutral particles, UV and soft X-rays.
Design features – it has an open input, the input window diameter is 9 mm.
The number of dynodes is 1.
SEM-6 channel is a thin tube with inner diameter of about 1.5 mm bent at a radius of 5 mm. The channel expands with a 65° cone to a diameter of 10 mm at the input end.
It is available in two versions – with adhesive or mechanical attachment of the multiplier and leads to the housing. SEM-6C version has an input grid.
Specification
Schematic diagram
Basic performance
Electrical ratings
| Parameter, unit | Value | |
|---|---|---|
| min | max | |
| Gain at ≤ 3300 V | 1×108 | — |
| Pulse height resolution at count rate of up to 1×104 counts/sec and U corresponding to 1×108 gain | — | 0.5 |
| Dark count rate, count/sec | — | 0.5 |
| Channel supply current at 4000 V, µA | 5 | 20 |
Electrical ratings changing during operation
| Parameter, unit | Value, max |
|---|---|
| Pulse height resolution at count rate of up to 1×104 counts/sec and U ≤ 3300 V | 0.8 |
| Increase of supply voltage at 1×108 gain, % | 15 |
Absolute maximum ratings
| Parameter, unit | Value, max |
|---|---|
| Gain | 7×108 |
| Supply voltage, V | 4000 |
| Average output current, µA | 1 |
| Count rate, count/sec | 105 |