I'm designing a Silicon Photomultiplier circuit with an amplifier. The base circuit can be shown below.
This was from SensL's recommended circuit layout for their Silicon Photomultiplier, the MicroFJ-60035-TSV. However, this is for one photomultiplier. I designed a board with four photomultipliers, each with their own op amp circuit, but I was wondering, if I used 4 photomultipliers and had their output go to one op amp, would there be any design considerations to think about? You can see the proposed schematic below, though the -30V bias was left out since it would be the same as the previous circuit. At first, I thought that this would act like a summing amplifier, with each photomultiplier contributing a voltage to the op amp; depending on the output voltage, you can detect how many photomultipliers 'fired'. Does this idea seem reasonable, or is there something I'm not taking into consideration?
EDIT: Below is a revised circuit used in LTspice. I tried modeling the photomultiplier with a pulsed current source in parallel with a capacitor and resistor