They provide cheap photon diodes with risetime less than 0.2 ns. For photomultipliers , I exclusively went to Hamamatsu . The quantum efficiency of photomultiplers is about 15 percent, depending on the wavelength and the cathode materials. To detect charged particles , use a microchannel plate . The height of the ion signal is dependent on the mass of the ions .
Light ions produce more secondary electrons, thus higher peak heights.
At the same mass, molecular ions produce more secondary electrons than atomic ions since molecular ions dissociate when they collide with the surface of the microchannel plate. Go to Hamamatsu to buy microchannel plates as well. A Microchannel plate is also sensitive to neutral particles if they are accelerated to high kinetic energies, or if they are in metastable states and have internal energies of a few electronvolts. If you need position sensitive photon detectors , go to Hamamatsu as well. They provide one-dimensional and two dimensional PSD's .