30 research outputs found
Development of high precision timing counter based on plastic scintillator with SiPM readout
No full textHigh-time-resolution counters based on plastic scintillator with silicon photomultiplier (SiPM) readout have been developed for applications to high energy physics experiments for which relatively large-sized counters are required.We have studied counter sizes up to 120 × 40 × 5 mm3 with series connection of multiple SiPMs to increase the sensitive area and thus achieve better time resolution. A readout scheme with analog shaping and digital waveform analysis is optimized to achieve the highest time resolution. The timing performance is measured using electrons from a 90Sr radioactive source, comparing different scintillators, counter dimensions, and types of near-ultraviolet sensitive SiPMs. As a result, a resolution of σ = 42±2 ps at 1MeV energy deposition is obtained for counter size 60 × 30 × 5 mm3 with three SiPMs ( 3 × 3 mm2 each) at each end of the scintillator. The time resolution improves with the number of photons detected by the SiPMs. The SiPMs from Hamamatsu Photonics give the best time resolution because of their high photon detection efficiency in the near-ultraviolet region. Further improvement is possible by increasing the number of SiPMs attached to the scintillator
Large Area A-thermal Phonon TES Detector Mediated by the quasi-particle Diffusion Signal for Space Application
No full textFirst Configurational Study of the CryoAC Detector Silicon Chip of the Athena X-Ray Observatory
No full textDesign and test of an extremely high resolution Timing Counter for the MEG II experiment: preliminary results
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Status of the MEG II experiment at PSI
No full textThe observation of charged Lepton Flavour Violating (cLFV) processes would be a definitive signature of physics beyond the Standard Model. The phase I one of the MEG experiment established the best upper limit on the branching ratio of one of the cLFV golden channels, μ →eγ: BR (μ →eγ) < 4.2 ×10-13 (@90% Confidence Level). This limit will be improved by about one order of magnitude by the phase II of the experiment, which is supposed to run for few years since 2022, taking advantage of a higher beam rate and an upgraded detector. In this talk, starting from MEG I experimental setup and results I will described MEG II improvements and expected sensitivity
Pixelated positron timing counter with SiPM-readout scintillator for MEG II experiment
No full textIn this paper, we introduce the positron timing counter (TC) for the MEG II experiment as an application of Silicon PhotoMultipliers (SiPM) to high-resolution timing measurement. MEG II will search for the μ → eγ decay and needs a precise measurement of the positron timing. The TC is segmented in 512 counters, composed of a scintillator plate readout by SiPMs, to obtain multiple hit positron timing simultaneously such to achieve an excellent overall timing resolution of ∼30 ps. We performed single counter R&D to optimize the choice of the SiPM manufacturer, the number of the SiPMs, and their connection. To obtain the best resolution, we decided to employ AdvanSiD SiPMs, six of which are attached at both ends connected in series. Moreover we carried out beam tests with 8-9 counters prototypes, where we proved that positron multiple hits improve the resolution according to expectation. The desgin phase of the TC is almost finished and is under construction
Direct Search for Low Energy Nuclear Isomeric Transition of Th-229m with TES Detector
No full textPrecise knowledge of the energy and lifetime of 229mTh isomeric state has notable importance as a basis for a nuclear clock. Such a clock would be capable to extend precision on the oscillator frequency by up to four orders of magnitude compared to the presently best atomic clocks. However, the technique proposed for the clock requires that the isomeric state energy is accessible with existing laser systems. Previous measurement placed this state at ∼8 eV (150 nm), in the Vacuum Ultra Violet (VUV) range of the electromagnetic spectrum. A precise direct measurement of the energy of this state is necessary to determine whether the nuclear clock can be made using existing laser technology. We are developing a cryogenic microcalorimeter to measure the energy and lifetime of the 229mTh isomeric state directly. The experiment will use a 233U source whose alpha-decay will populate the 229mTh isomeric state with 2% probability. The subsequent decay of 229mTh will be measured by a Transition Edge Sensor (TES) with <1 eV resolution. Such a technique will allow to observe all possible types of decays of 229mTh in the range of energy from 3 to 50 eV and lifetimes >5 microseconds. The single-photon TES has sufficient resolving power combined with high efficiency in the whole energy band for this experiment. Here we present a prototype of TES based on a 200 nm thick iridium-gold (Ir/Au) film which was tested with a pulsed laser source and demonstrated ∼0.8 eV energy resolution and 5.8 ± 2.1 μs signal recovery time
