MEASARminus for use of an array of CEMs with negative high voltage
MEASARminus is a modular electronic instrument to operate systems with multiple channel electron multipliers (CEMs) or photomultipliers (PMTs) and evaluate all output signals simultaneously by pulse counting as well as current and integral charge measurements.
It consists of a mechanical housing in 19"-subrack technology, with a module high voltage generation, pulse counting, current and charge monitoring, and one system controller module with an RS 232-interface, which may easily be translated to USB by means of an external bridging circuit, to connect the system to a host computer. The computer sets the high voltage, discriminator threshold, and measurement time. Measurements can be run one per start command or automatically repeated.
| |
|
Units |
Range |
| |
|
|
|
| |
High Voltage |
V |
- 128 to - 4095 |
| |
HV slope (1 bit) |
V/s |
±100 or ±800 |
| |
Preamplifier threshold |
mV |
- 3 to - 130.5, step size = 0.5 |
| |
Preamplifier deadtime |
ns |
15 - 30 - 60 - 100 |
| |
Measurement time interval |
ms
|
unlimited, stop by command, or |
(1 to 65535) x 10 |
| |
Measurement repetitions |
|
unlimited, stop by command, or |
| |
|
1 to 255 automatically repeated |
| |
CEM overload protection |
µA |
max. anode current (1-15) x 1.024 |
| |
Current measuring |
µA |
full scale = 16.38375 |
| |
Charge accumulation |
nC |
up to 335.54 µC |
| |
Anode bias |
V |
- 120 (±10) |
| |
|
|
|
| |
|
|
|
