Fast pulse amplifiers for scintillation output from PMT

A fast opamp, an AD8001 or something, should work OK. At these speeds, and to keep up linearity, you might go for two stages, with a gain of

Several people make small wideband amp boxes... names escape me at this instant. I'm considering doing some myself, but not this week.

You could also get a voltage gain of 10 from a single MMIC, maybe a low-noise SiGe part, like SGA-3586, but it would be AC coupled, and invert.

John

Do you have an estimate of the outut impedance of the PMT and the input impedance of the Single Channel Analyzer?

I think the impedance macthing is not a problem now, the load resistor and signal cable and the anti-reflection resistor behind the PMT are all fixed 50ohm, the SNR is good, thus the reason why the pulse height is not enough (only 6mV) is mainly physics factors. So following work should be enhance the pulse height by two means: electronic amplification and increase the photon collection effciency of the photomultiplier, while the latter maybe difficult, so the best solution should still be fast pulse amplification.

Thank you John, for the advices on the amplifier, I tried the typical spectroscopy amplifier and a charge-sensitive preamplifier respectively, both NIM module, but not signal displayed on the osciliscope, maybe the frequency ability of these two are far not enough for such an fast pulse amplification.

Becker-Hickl offers amplifier designed for this application (see

However I guess for a reasonable linearity of a poisson distributed pulse source up to 10^8cps, as a PMT is, you will need one with a narrower puls than

how about a trasformer?

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Bye. Jasen

oh, maybe it is also a method..I am not familiar with this, but how about the time resolution?or the frequency performance ?