[en] A new type of photon detector, the Geiger-mode avalanche photodiode (G-APD) has been developed during recent years. This device has the potential to replace photomultiplier tubes. It has a response to single photons with high detection efficiency. G-APDs are operated in Geiger mode and therefore the recovery time, the time needed until the small photodiodes of this device are fully active again after a breakdown, is a crucial parameter in applications with a high level of ambient light. The recovery time of several types of G-APDs was measured and the results are presented

[en] Multi-cell avalanche photodiodes (APDs) operating in Geiger mode have been shown to be a very promising alternative to photomultiplier tubes for the detection of single photons at room temperature. Like a photomultiplier they have high gain and a fast rise time and they are insensitive to pickup. Beyond it they operate in high magnetic fields, are compact and need a relatively low bias voltage. It is expected that the MOS production technique makes them cheap. Recently PSI and Hamamatsu Photonics worked together for the development of a radiation-hard APD for CMS ECAL and had very good success. The development continued based on a similar design for a photon counting multielement Geiger-mode APD with an area of 1x1 mm². The properties of this device have been measured and will be reported

[en] The Hamamatsu Photonics S8148 large area Avalanche Photo Diodes (APD) were designed for the crystal electromagnetic calorimeter of the CMS setup at LHC in a close collaboration of Hamamatsu Photonics and CMS APD group (PSI, Northeastern University and University of Minnesota). All essential parameters of these devices are controlled by the producer and are fairly stable during the mass production, except the radiation hardness. To insure 99.9% reliability of APDs in the radiation hard environment of LHC, the CMS APD group had to invent a dedicated screening procedure. The details of this procedure and some results of the screening are discussed

[en] We report on first tests of Geiger-mode APDs (G-APD) to detect Cherenkov light from cosmic particle induced air showers. The motivation for this study stems from the requirement to improve the sensitivity of large imaging atmospheric Cherenkov telescopes (IACT) by replacing the photomultipliers (PMT) by high detection efficiency G-APDs. Three tests have been carried out, confirming sufficiently high light sensitivity of blue-sensitive G-APDs as future replacement of PMTs in IACTs

[en] Recently developed multipixel Geiger-mode avalanche photodiodes (G-APDs) are very promising candidates for the detection of light in medical imaging instruments (e.g. positron emission tomography) as well as in high-energy physics experiments and astrophysical applications. G-APDs are especially well suited for morpho-functional imaging (multimodality PET/CT, SPECT/CT, PET/MRI, SPECT/MRI). G-APDs have many advantages compared to conventional photosensors such as photomultiplier tubes because of their compact size, low-power consumption, high quantum efficiency and insensitivity to magnetic fields. Compared to avalanche photodiodes and PIN diodes, they are advantageous because of their high gain, reduced sensitivity to pick up and the so-called nuclear counter effect and lower noise. We present measurements of the basic G-APD characteristics: photon detection efficiency, gain, inter-cell crosstalk, dynamic range, recovery time and dark count rate

[en] Specially developed avalanche photodiodes (APDs) will be used to measure the light from the 61,200 lead tungstate crystals in the barrel part of the CMS electromagnetic calorimeter. To ensure the reliability over the lifetime of the detector, every APD is screened by irradiation and burn-in before it is accepted for CMS. As part of the establishment of the screening procedure and to determine its effectiveness, a large number of APDs were screened twice. The results of these tests suggest that the required reliability will be achieved

[en] We have detected Cherenkov light from air showers with Geigermode-APDs (G-APDs). G-APDs are novel semiconductor photon detectors, which offer several advantages compared to conventional photomultiplier tubes in the field of ground-based very high energy (VHE) γ-ray astronomy. In a field test with the MAGIC telescope we have tested the efficiency of a G-APD/light catcher setup to detect coinciding Cherenkov light from air showers. From our test we estimate a detection efficiency of our G-APD/light catcher setup to be ≥60% higher than the efficiency of a MAGIC camera pixel. The dark count rates of the tested G-APD at ambient temperature are 10 times lower than the rates of detected photons from the night sky light background (NSB). This relaxes the need for cooling the G-APD to the level where the noise rate is sufficiently low. According to this recent test, G-APDs promise a major progress in ground-based VHE γ-ray astronomy.

[en] In this work we report on tests of Avalanche Microchannel PhotoDiodes (AMPDs) for the use in scintillation detectors. The obtained results show large potential of AMPDs for development of compact, magnetic field insensitive detectors comparable in performance with those based on photomultiplier tubes

[en] Avalanche Photodiodes (APDs) are now out of their infancy and are used in large numbers in the electromagnetic calorimeter of CMS where they have to stand the extremely hostile environment of LHC. This type--with smaller sensitive area and arranged in monolithic arrays--is an excellent candidate for the read out of scintillating crystals in medical imaging and a PET scanner operates already successfully since more than 3 years. We present the properties of the device used in CMS and possible improvements of the structure, which could open the door for new applications. Operating APDs at low temperatures or in Geiger mode will allow single photon counting and in future they could replace photomultiplier tubes

[en] Avalanche Microchannel PhotoDiodes (AMPDs) are solid state photodetectors with high internal gain and a density of independent channels up to 10⁴/mm². They are potential substitutes for photomultiplier tubes in a wide variety of applications in nuclear physics and nuclear medicine, especially when fine segmentation of the detectors and their operation in high magnetic fields is required. In this work, we study the performance of a detector based on a LYSO (2x2x10 mm³) scintillation crystal and AMPD at detection of 511 keV γ-quanta. The detector shows linear energy response, an energy resolution of ∼12%, and sub-nanosecond time resolution. These characteristics are encouraging for using AMPDs in detector systems of positron emission tomographs (PET) of the next generation