SensL C-, Jand R-Series SiPM sensors have a fast, capacitively coupled output that gives a high speed output signal, which is suitable for timing applications. Summing the fast output directly is not recommended as this would negatively affect the resulting signal. By introducing a diode pair (fast Schottky) as shown in Figure 1, the Fast signal from the active SiPM is transferred to the Common...

The quality of the 20 in . photomultiplier tubes (Hamamatsu R1449) has been greatly improved over the required specifications for using them m the 50000 ton imaging water Cherenkov detector, Super-Kamiokande . In particular, the resolution of the timing response for single-photoelectron light has been reduced to 3 ns (1Q width), and a clear single-photoelectron peak can be seen in the pulse hei...

We have developed a simple and rapid technique for measuring the action spectra for phototaxis of populations of microorganisms and applied it to halobacteria. A microscope with a dark-field condenser was used to illuminate the cell suspension in a sealed chamber with light of wavelength greater than 750 nm; in this region of the spectrum, the halobacteria show no phototactic response. A 150-mi...

The Silicon Photomultiplier (SPM) offers sensitivity comparable to conventional photomultipliers with the added advantage of small size, low operating voltages, and robust tolerance to excess/ambient light. A Peltier cooled SPM running at -30°C was used in conjunction with wideband electronics and a 17-inch Astrograph to collect photometric data without a reference star. High speed photometric ...

This note describes continued studies at Fermilab of the long term stability of a small water Cerenkov tank. The water tank, bag liner, water, photomultiplier tube, and data acquisition software were unchanged for the additional measurements from June to November, 1999. However, some details of the geometry of the trigger counters relative to the tank and of the electronics may have differed. T...

Abstract It is critical to construct an accurate optical model of photomultiplier tubes (PMTs) in many applications describe the angular and spectral responses photon detection efficiency (PDE) PMTs their working media. In this study, we propose a new PMT both light interactions with window processes inside reasonable accuracy based on optics theory GEANT4-based simulation toolkit. The proposed...