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Institute: University of Insubria

The Silicon PhotoMultiplier (SiPM) consists of a high‐density (up to ~103 /mm2) matrix of diodes connected in parallel on a common Si substrate. Each diode is an Avalanche Photo Diode (APD) operated in a limited Geiger‐Müller regime connected in series with a quenching resistance, in order to achieve gain at level of 105 ‐ 106. Fig. 1 shows the equivalent circuit of a SiPM. As a consequence, these detectors are sensitive to single photons (even at room temperature) feature a dynamic range well above 100 photons/burst and have a reasonable Photon Detection Efficiency (PDE). Moreover the SiPM measures the light intensity simply by the number of fired cells.