Oct 22 2012 RMD APDs 2 x 2

Oct. 22, 2012 RMD APDs 2 x 2 mm 2 Other information 8 x 8 mm 2 indium dc capacitance 8 x 8 mm 2 Al-coated

Oct. 22, 2012 RMD APDs Other information APD signal pulse shape dependence on incidence angle NONE 8 x 8 mm 2 APD

Oct. 22, 2012 RMD APDs Other information Temporal response of APDs 980 nm Vcsel, ~1 ns pulse, 1 k. Hz 1. 3 x 104 photons/pulse, spot size <100 µm APD bias at -1. 75 k. V response of APDs to Am 241 - α-particle APD bias at -1. 75 k. V Their tfall time is significantly different than trise Indium and Al-coated APDs have broader pulse widths

Oct. 22, 2012 RMD APDs Other information Noise of APD, 8 x 8 mm 2 device Output of APD is sent to BNL-IO-535 charge sensitive preamplifier followed by Ortec-474 timing filter amplifier with 0. 5 µs shaping time. By knowing the electron charge calibration of the preamp+shaping amplifier, 104 electrons = 85 m. V signal pulse amplitude, the APD noise is measured by the quadrature subtraction on the rms voltages at the output of the shaping amplifier with and without – 1. 75 k. V bias on the APD (w/o photons), they are 7. 8 and 7. 2 m. V, respectively. APD noise is ~350 rms electrons at -1. 75 k. V bias Representative shaping amplifier output signal with 1. 3 x 104 photons/pulse on APD, 980 nm Vcsel, ~1 ns pulse, 1 k. Hz, spot size <100 µm, APD bias at -1. 75 k. V rms voltage noise