Photon readout of plastic scintillators is investigated with the aim of improving the precision of neutron \b{eta} decay experiments. Neutron decay is nowadays studied with high statistics, based on up to 109 registered decay events, and leads to strongly improved limits on new physics beyond the standard model, with \b{eta}s often registered in plastic scintillators. The main systematic errors in these experiments are due to imperfect characterization of the scintillators with respect to linearity, energy resolution, and electron backscattering. We study whether these errors can be diminished when the conventional photomultipliers used for scintillator readout are replaced by silicon photomultipliers (SiPMs). To this end, various theoretical and experimental tools are developed, and a procedure for handling the extreme dark rates of SiPMs is proposed. In \b{eta} spectroscopy, so the conclusion, plastic scintillator readout with SiPMs can significantly improve energy response, and help providing reliable corrections for electron backscattering.
This paper proposes an automatic procedure, based on ROOT data Analysis Framework, for the analysis of Silicon Photomultipliers (SiPM) characteristics. In particular, it can be used to analyze experimental waveforms, from oscilloscope, containing SiPM pulses acquired at different temperatures and bias voltages. Important SiPMs characteristics such as: charge distribution, gain, breakdown voltage, pulse shape (rise time and recovery time) and overvoltage can been calculated. Developed procedure can be easily used to analyze any type of SiPM detectors.
Dark count rate and correlated noise rate are among the main parameters that characterize silicon photomultipliers (SiPM). Typically, these parameters are evaluated by applying approximate formulas, or by fitting specific models, to the measured SiPM noise spectra. Here a novel approach is presented, where exact formulas are derived from a statistical model of dark counts and correlated noise generation. The method allows one to measure the true value of such parameters from the areas of just the first peaks in the dark spectrum. A numerical analysis shows the accuracy of the method.
We compared the performance of a SiPM array and a PMT in a laboratory setting using a single 5.08x5.08-cm cylindrical sodium iodide scintillating crystal. Photomultiplier tubes (PMTs) are the most commonly used device to monitor scintillating materials for radiation detection purposes. The systems are sometimes limited by disadvantages in the PMTs that may degrade their performance, including temperature dependence and variation with magnetic field. Instrumentation engineering must also contend with a potentially large volume relative to the active scintillator volume, fragility, and high volt…
Study of the response and photon-counting resolution of silicon photomultipliers using a generic simulation framework
我们提出了一个通用的框架模拟的硅光电倍增器（SiPMs），使详细的建模的SiPM响应使用基本的SiPM参数和几何形状作为输入。根据指定的SiPM属性，可以确定从基本的表征测量，模拟生成的信号电荷和脉冲形状的任意入射光脉冲分布。模拟已在整个动态范围内验证了滨松S10362-11- 100 C MPPC，并用于研究不同的噪声源，如光串扰和后脉冲的响应曲线和光子计数分辨率的影响。
The avalanche breakdown and Geiger mode of the silicon p-n junction is considered. A precise physically motivated method is proposed for determining the avalanche breakdown voltage of silicon photomultipliers (Si PM). The method is based on measuring the dependence of the relative photon detection efficiency (PDErel ) on the bias voltage when one type of carriers (electron or hole) is injected into the avalanche multiplication zone of the p-n junction. The injection of electrons or holes from the base region of the Si PM semiconductor structure is performed using short-wave or long-wave light.…
Silicon photomultipliers (SiPMs) have a low radioactivity, compact geometry, low operation voltage, and reasonable photo-detection efficiency for vacuum ultraviolet light (VUV). Therefore it has the potential to replace photomultiplier tubes (PMTs) for future dark matter experiments with liquid xenon (LXe). However, SiPMs have nearly two orders of magnitude higher dark count rate (DCR) compared to that of PMTs at the LXe temperature ($\sim$ 165 K). This type of high DCR mainly originates from the carriers that are generated by band-to-band tunneling effect. To suppress the tunneling effect, we…
Due to their very fast signal rise time in the order of 1 ns, Silicon-Photomultipliers have become of increasing interest for many experiments that require very good timing resolution. With the prospect of an application in medical imaging techniques like a Compton Camera or TOF-PET, a coincident detection of Cherenkov photons from electrons in the MeV range in PMMA has been performed. A 4x4 SiPM-array was used for this purpose and a timing resolution of 242 ps has been achieved. A spatial sensitivity for an electron source location could be shown using accumulated coincident light signals. Ob…
Plastic scintillation detectors represent an efficient, cost-effective, customizable solution for assessment of gamma radiation fields in the context of nuclear security, environmental radiation survey, radiological and nuclear incidents response (RNe) and dosimetry for radiation protection purposes. Solid state light readout technologies such as Silicon Photomultiplier diodes (SiPM) are characterized by low operational voltage, mechanical robustness, compact dimensions, and fast pulse rise-time. Due to these intrinsic advantages, Silicon Photomultiplier diodes have been progressively replacin…
Metalenses are optical devices that implement nanostructures as phase shifters to focus incident light. Their compactness and simple fabrication make them a potential cost-effective solution for increasing light collection efficiency in particle detectors with limited photosensitive area coverage. Here we report on the characterization and performance of metalenses in increasing the light collection efficiency of silicon photomultipliers (SiPM) of various sizes using an LED of 630~nm, and find a six to seven-fold increase in signal for a $1.3\times1.3~\mathrm{mm}^2$ SiPM when coupled with a 10…
We report on the design and commissioning of a new spectrometer for muon-spin relaxation/rotation studies installed at the Swiss Muon Source (S$μ$S) of the Paul Scherrer Institute (PSI, Switzerland). This new instrument is essentially a new design and replaces the old general-purpose surface-muon instrument (GPS) which has been for long the workhorse of the $μ$SR user facility at PSI. By making use of muon and positron detectors made of plastic scintillators read out by silicon photomultipliers (SiPMs), a time resolution of the complete instrument of about 160 ps (standard deviation) could be …
The light yield, the time resolution and the efficiency of different types of scintillating tiles with direct Silicon Photomultiplier readout and instrumented with a customised front-end electronics have been measured at the Beam Test Facility of Laboratori Nazionali di Frascati and several test stands. The results obtained with different configurations are presented. A time resolution of the order of 300 ps, a light yield of more than 230 photo-electrons, and an efficiency better than 99.8 $\%$ are obtained with $\sim 225$ cm$^2$ large area tiles. This technology is suitable for a wide range …
In this article we describe the photon detection readout electronics for the nEDM@SNS experiment. The chosen "photon counting" architecture, which utilizes high-efficiency silicon photomultipliers (SiPMs) and is appropriate for low-light applications, allows the use of a relatively high SiPM operating voltage. This maximizes photon detection efficiency and minimizes gain/efficiency voltage-dependence while eliminating optical cross-talk.
The performance of several trigger counters based on plastic scintillators with silicon photomultiplier readout is investigated with cosmic rays. Efficiency and time resolution are measured using digital waveform analysis. The obtained results are relevant for trigger subsystems of Multi-Purpose Detector (MPD) and Baryonic Matter at the Nuclotron (BM@N) at the NICA heavy-ion collider. The results show very high efficiency and good timing performance of the counters.
Silicon Photomultipliers (SiPMs) are considered as a solid-state sensor alternative to photomultiplier tubes in experiments using liquid xenon (LXe) as a radiation detection medium. The main requirements are single-photon detection of the vacuum ultraviolet scintillation light from LXe at 178$\,$nm with high resolution and detection efficiency and low noise rates. Further requirements for dark matter and double beta decay searches are ultra-low radioactivity levels of all the components including the substrates and cold electronics. Here we describe our characterisation of Hamamatsu 6$\times$6…
The application of silicon photomultiplier (SiPM) technology for weak-light detection at a single photon level has expanded thanks to its better photon detection efficiency in comparison to a conventional photomultiplier tube (PMT). SiPMs with large detection area have recently become commercially available, enabling applications where the photon flux is low both temporarily and spatially. On the other hand, several drawbacks exist in the usage of SiPMs such as a higher dark count rate, many readout channels, slow response time, and optical crosstalk; therefore, users need to carefully conside…
The results obtained in laboratory tests, using scintillator bars read by silicon photomultipliers are reported. The present approach is the first step for designing a precision tracking system to be placed inside a free magnetized volume for the charge identification of low energy crossing particles. The devised system is demonstrated able to provide a spatial resolution better than 2 mm.
To increase the light yield of a liquid Ar (LAr) detector, we optimized the evaporation technique of tetraphenyl butadiene (TPB) on the detector surface and tested the operability of a silicon photomultiplier (SiPM), namely, the multi-pixel photon counter with through-silicon-via (TSV-MPPC, Hamamatsu Photonics K.K.) at LAr temperature. TPB converts the LAr scintillations (vacuum ultraviolet light) to visible light, which can be detected by high-sensitivity photosensors. Because the light yield depends on the deposition mass of TPB on the inner surface of the detector, we constructed a well-con…
We propose and study a method of optical crosstalk suppression for silicon photomultipliers (SiPMs) using optical filters. We demonstrate that attaching absorptive visible bandpass filters to the SiPM can substantially reduce the optical crosstalk. Measurements suggest that the absorption of near infrared light is important to achieve this suppression. The proposed technique can be easily applied to suppress the optical crosstalk in SiPMs in cases where filtering near infrared light is compatible with the application.
The main effect of radiation damage in a Silicon-Photolumtiplier (SiPM) is a dramatic increase in the dark current. The power dissipated, if not properly cooled, heats the SiPM, whose performance parameters depend on temperature. Heating studies were performed with a KETEK SiPM, glued on an Al$_2$O$_3$ substrate, which is either directly connected to the temperature-controlled chuck of a probe station, or through layers of material with well-known thermal resistance. The SiPM is illuminated by a LED operated in DC-mode. The SiPM current is measured and used to determine the steady-state temper…
Silicon photomultipliers (SiPMs) have become popular light conversion devices in recent years due to their low bias voltage and sensitivity to wavelengths emitted from common scintillating materials. These properties make them particularly attractive for resource-constrained missions such as space-based detector applications. However the space radiation environment is known to be particularly harsh on semiconductor devices, where high particle fluences can degrade performance over time. The radiation hardness of a particular SiPM, manufactured by ON Semiconductor (formally SensL), has yet to b…
Radiation Damage Studies of Silicon Photomultipliers
我们报告的硅光电倍增器（SiPM）的辐射硬度的测量由布鲁诺凯斯勒基金会在意大利（1 mm $^2$和6.2 mm $^2$），透视技术和仪器中心在俄罗斯（1 mm $^2$和4.4 mm $^2$），日本滨松公司（1 mm $^2$）。在Massachusetts General Hospital使用212 MeV质子束照射SiPM，SiPM在工作电压下接收高达$3 \times 10^{10}$质子/cm $^2$的注量。在照射期间连续读取漏电流。周期性地暂停质子的递送以记录响应于校准光脉冲的示波器迹线，以监测SiPM的增益、光子检测效率和暗计数。漏电流和暗噪声随注量的增加而增加。Te漏电流被发现是成比例的噪声分布的均方差，表明暗计数是由于增加随机个别像素激活，而SiPM仍然完全功能的光子探测器。发现SiPM在室温下退火，在大约100天内漏电流减少了2倍。
Silicon photomultipliers are photon-number-resolving detectors endowed with hundreds of cells enabling them to reveal high-populated quantum optical states. In this paper, we address such a goal by showing the possible acquisition strategies that can be adopted and discussing their advantages and limitations. In particular, we determine the best acquisition solution in order to properly reveal the nature, either classical or nonclassical, of mesoscopic quantum optical states.
A detailed and accurate characterisation of silicon photomultiplier detectors is required for a better understanding of the signal and noise in many applications. The collected information is a valuable feedback to the manufacturers in their attempt to improve the performances. In this paper, we provide a detailed description of how to characterise these photo-detectors. The correlated noise probabilities, the important time constants and the photon detection efficiency are obtained with a statistical analysis of pulse-shape and time distributions. The method is tested with different detectors…
Scintillation characteristics of a thallium doped sodium iodide (NaI(Tl)) crystal with a dimension of 0.6 x 0.6 x 2 cm3 are studied by attaching a silicon photomultiplier (SiPM) direct to the crystal over a temperature range from 93 to 300 K. The scintillation light output and decay time are measured by irradiating 59.54 keV gamma-rays from a 241Am source. We observed approximately 20% increase in light yield at 230K compared to that at the room temperature. At this condition, the NaI(Tl) crystal coupled with the SiPM can be a good candidate for future dark matter search detector.
The Muon Telescope is a muography experiment for imaging volcanoes in Colombia. It consists of a scintillator tracking system and a water Cherenkov detector used for particle deposited energy measurement. The MuTe operates autonomously in high altitude environments where the temperature gradient reaches up to $10$$^{\circ}$C. In this work, we characterize the breakdown voltage, gain, and noise of the telescope silicon photomultipliers for temperature variations spanning $0$ to $40$$^{\circ}$C. We demonstrated that the discrimination threshold for the MuTe hodoscope must be above 5 pe to avoid …
Radiation hardness is an important requirement for solid state readout devices operating in high radiation environments common in particle physics experiments. The MEGII experiment, at PSI, Switzerland, investigates the forbidden decay $μ^+ \to \mathrm{e}^+ γ$. Exploiting the most intense muon beam of the world. A significant flux of non-thermal neutrons (kinetic energy $E_k\geq 0.5 ~MeV$) is present in the experimental hall produced along the beamline and in the hall itself. We present the effects of neutron fluxes comparable to the MEGII expected doses on several Silicon PhotoMulitpliers (Si…
A statistical model of the nonlinear response of silicon photomultipliers is presented. It includes losses of both the photodetection efficiency and the gain during pixel recovery periods as well as the effect of correlated and uncorrelated noise. The model provides either the mean output charge of a SiPM for incident light pulses of arbitrary shape or the output current for continuous light. The dependence of the SiPM response on both the overvoltage and the pulse shape is also properly described. The model has been validated for two different silicon photomultipliers using scintillation ligh…
Silicon photomultiplier arrays - a novel photon detector for a high resolution tracker produced at FBK-irst, Italy
在FBK-irst研制了一个硅光电倍增器（SiPM）阵列，它有32个通道，尺寸为8.0 x 1.1 mm^2。每个250 um宽的通道被细分为5 x 22个矩形排列的像素。这些传感器被开发用于读出模块化高分辨率的光纤跟踪器。关键属性，如击穿电压，增益和光子探测效率（PDE）被发现是均匀的SiPM阵列的所有32个通道。如果噪声特性和PDE得到改善，这可以使具有SiPM阵列读出的光纤跟踪器成为可用跟踪器技术的有希望的替代方案。
We present light yield and uniformity measurements of square and hexagonal tiles read out with silicon photomultipliers via a Y11 wavelength-shifting fiber or directly from the side or from the center at the top face. All tiles are 3~mm thick and have an area of $\rm 9~cm^2$. The sides are wrapped with two layers of Teflon tape while top and bottom faces are covered with two layers of Tyvec paper. We further show the first light yield and uniformity measurements of ATLAS Tile Calorimeter (TileCal) tiles with MPPC readout. This study has been motivated by looking into a possible phase 3 upgrade…
