Novel technique for the study of pile-up events in cryogenic bolometers
A. Armatol, E. Armengaud, W. Armstrong, C. Augier, F. T. Avignone, O. Azzolini, A. Barabash, G. Bari, A. Barresi, D. Baudin, F. Bellini, G. Benato, M. Beretta, … 展开作者
A. Armatol, E. Armengaud, W. Armstrong, C. Augier, F. T. Avignone, O. Azzolini, A. Barabash, G. Bari, A. Barresi, D. Baudin, F. Bellini, G. Benato, M. Beretta, L. Bergé, M. Biassoni, J. Billard, V. Boldrini, A. Branca, C. Brofferio, C. Bucci, J. Camilleri, S. Capelli, L. Cappelli, L. Cardani, P. Carniti, N. Casali, A. Cazes, E. Celi, C. Chang, M. Chapellier, A. Charrier, D. Chiesa, M. Clemenza, I. Colantoni, F. Collamati, S. Copello, O. Cremonesi, R. J. Creswick, A. Cruciani, A. D'Addabbo, G. D'Imperio, I. Dafinei, F. A. Danevich, M. de Combarieu, M. De Jesus, P. de Marcillac, S. Dell'Oro, S. Di Domizio, V. Dompè, A. Drobizhev, L. Dumoulin, G. Fantini, M. Faverzani, E. Ferri, F. Ferri, F. Ferroni, E. Figueroa-Feliciano, J. Formaggio, A. Franceschi, C. Fu, S. Fu, B. K. Fujikawa, J. Gascon, A. Giachero, L. Gironi, A. Giuliani, P. Gorla, C. Gotti, P. Gras, M. Gros, T. D. Gutierrez, K. Han, E. V. Hansen, K. M. Heeger, D. L. Helis, H. Z. Huang, R. G. Huang, L. Imbert, J. Johnston, A. Juillard, G. Karapetrov, G. Keppel, H. Khalife, V. V. Kobychev, Yu. G. Kolomensky, S. Konovalov, Y. Liu, P. Loaiza, L. Ma, M. Madhukuttan, F. Mancarella, R. Mariam, L. Marini, S. Marnieros, M. Martinez, R. H. Maruyama, B. Mauri, D. Mayer, Y. Mei, S. Milana, D. Misiak, T. Napolitano, M. Nastasi, X. F. Navick, J. Nikkel, R. Nipoti, S. Nisi, C. Nones, E. B. Norman, V. Novosad, I. Nutini, T. O'Donnell, E. Olivieri, C. Oriol, J. L. Ouellet, S. Pagan, C. Pagliarone, L. Pagnanini, P. Pari, L. Pattavina, B. Paul, M. Pavan, H. Peng, G. Pessina, V. Pettinacci, C. Pira, S. Pirro, D. V. Poda, T. Polakovic, O. G. Polischuk, S. Pozzi, E. Previtali, A. Puiu, A. Ressa, R. Rizzoli, C. Rosenfeld, C. Rusconi, V. Sanglard, J. Scarpaci, B. Schmidt, V. Sharma, V. Shlegel, V. Singh, M. Sisti, D. Speller, P. T. Surukuchi, L. Taffarello, O. Tellier, C. Tomei, V. I. Tretyak, A. Tsymbaliuk, M. Velazquez, K. J. Vetter, S. L. Wagaarachchi, G. Wang, L. Wang, B. Welliver, J. Wilson, K. Wilson, L. A. Winslow, M. Xue, L. Yan, J. Yang, V. Yefremenko, V. Yumatov, M. M. Zarytskyy, J. Zhang, A. Zolotarova, S. Zucchelli
Precise characterization of detector time resolution is of crucial importance for next-generation cryogenic-bolometer experiments searching for neutrinoless double-beta decay, such as CUPID, in order to reject background due to pile-up of two-neutrino double-beta decay events. In this paper, we describe a technique developed to study the pile-up rejection capability of cryogenic bolometers. Our approach, which consists of producing controlled pile-up events with a programmable waveform generator, has the benefit that we can reliably and reproducibly control the time separation and relative energy of the individual components of the generated pile-up events. The resulting data allow us to optimize and benchmark analysis strategies to discriminate between individual and pile-up pulses. We describe a test of this technique performed with a small array of detectors at the Laboratori Nazionali del Gran Sasso, in Italy; we obtain a 90% rejection efficiency against pulser-generated pile-up events with rise time of ~15ms down to time separation between the individual events of about 2ms.
This paper reports the detailed noise characterization, investigation of various noise sources and its mitigation to improve the performance of a cryogenic bolometer detector. The noise spectrum has been measured for a sapphire bolometer test setup with indigenously developed NTD Ge sensor in the CFDR system at Mumbai. The effect of external noise, arising either from ground loops in the system or from the diagnostic and control electronics of the cryostat, on the performance of a cryogenic bolometer is assessed. A systematic comparison of the influence of different noise pickups on the bolome…
This paper presents an analytical model to quantify the measured noise in a cryogenic bolometer readout circuit. The model includes the contributions from the bias resistors and sensor resistors, voltage and current noise of amplifier, and cable capacitance. The model parameters are empirically estimated using frequency domain analysis of the measured noise data of indigenously developed Neutron Transmutation Doped (NTD) Ge sensors. The model is shown to describe noise data for NTD Ge sensors over a wide range of resistances corresponding to temperatures in the range 20 - 70 mK. Relative contr…
The aim of the SELENDIS project within the EDELWEISS collaboration is to observe single $e^- h^+$ pairs in lightweight (3.3 g) cryogenic germanium bolometers with charge and phonon readout at biases up to $\sim 100$ V. These devices are ideal to characterize in detail the mechanism of charge creation and collection in cryogenic germanium detectors. Electron-hole pairs are produced in the bulk of the detector either by the injection of pulsed IR laser or by neutron activation of germanium inducing the K, L and M lines from $^{71}$Ge electron capture decays. Low-energy laser pulses are also used…
The Cryogenic Underground Observatory for Rare Events (CUORE) is a ton-scale cryogenic experiment designed to search for neutrinoless double-beta decay of $^{130}$Te and other rare events. The CUORE detector consists of 988 TeO$_2$ bolometers operated underground at 10 mK in a dilution refrigerator at the Laboratori Nazionali del Gran Sasso. Candidate events are identified through a precise measurement of their energy. The absolute energy response of the detectors is established by the regular calibration of each individual bolometer using gamma sources. The close-packed configuration of the C…
We have developed preamplifier configurations used to readout resistive bolometers such as those based on Neutron Transmuted Doped Germanium thermometers (so called NTD Ge thermometers)[1] or NbSi thin film thermometers [2, 3]. We introduce the impedance regulating preamplifier configuration. This configuration, is compared to previously proposed readout configurations with feedback on the bolometer [4]. It is shown that the impedance regulating preamplifier achieves Extreme Electrothermal Feedback without using transition edge thermometer and SQUID readout. Thus the detector and readout elect…
Institute of High Energy Physics（高能物理研究所）；Austrian Academy of Sciences（奥地利科学院）
In high-background or calibration measurements with cryogenic particle detectors, a significant share of the exposure is lost due to pile-up of recoil events. We propose a method for the separation of pile-up events with an LSTM neural network and evaluate its performance on an exemplary data set. Despite a non-linear detector response function, we can reconstruct the ground truth of a severely distorted energy spectrum reasonably well.
We demonstrate that Neganov-Luke amplified cryogenic light detectors with Transition Edge Sensor read-out can be applied for the background suppression in cryogenic experiments searching for the neutrinoless double beta decay of $^{130}\text{Te}$ with TeO$_{2}$ based bolometers. Electron and gamma induced events can be discriminated from $α$ events by detecting the Cherenkov light produced by the $β$ particles emitted in the decay. We use the Cherenkov light produced by events in the full energy peak of $^{208}\text{Tl}$ and by events from a $^{147}\text{Sm}$ source to show that at the Q-value…
An active discrimination of the dominant $α$-background is the prerequisite for future neutrinoless double-beta decay experiments based on TeO$_{2}$ bolometers. We investigate such $α$-particle rejection in cryogenic TeO$_{2}$ bolometers by the detection of Cherenkov light. For a setup consisting of a massive TeO$_{2}$ crystal (285 g) and a separate cryogenic light detector, both using transition edge sensors as temperature sensors operated at around 10 mK, we obtain an event-by-event identification of e/$γ$- and $α$-events. We find in the energy interval ranging from 2400 keV to 2800 keV and …
We implemented a low noise current preamplifier for the readout of resistive bolometers. We tested the apparatus on thermometer resistances ranging from 10 Ohm to 500 Mohm. The use of current preamplifier overcomes constraints introduced by the readout time constant due to the thermometer resistance and the input capacitance. Using cold JFETs, this preamplifier board is shown to have very low noise: the Johnson noise of the source resistor (1 fA/Hz1/2) dominated in our noise measurements. We also implemented a lock-in chain using this preamplifier. Because of fast risetime, compensation of the…
Pulse-tube based dilution refrigerators are massively employed in low temperature physics. They allow to reduce the running costs and to be operated with unprecedented easiness. However, the main drawback of this technology is the mechanical vibrations induced by the pulse-tube cryocooler. These perturbations can cause extra-noises drastically affecting the detector performance. In this paper, we propose a solution to mitigate the impact of these vibrations by mounting the detectors in an elastic-pendulum based suspended tower. Based on vibration modeling and experimental tests, we show that t…
We present three Monte Carlo models for the propagation of athermal phonons in the diamond absorber of a composite semiconducting bolometer `Bolo 184'. Previous measurements of the response of this bolometer to impacts by $α$ particles show a strong dependence on the location of particle incidence, and the shape of the response function is determined by the propagation and thermalisation of athermal phonons. The specific mechanisms of athermal phonon propagation at this time were undetermined, and hence we have developed three models for probing this behaviour by attempting to reproduce the st…
Bolometers have proven to be good detectors for the search of neutrinoless double beta decay. By operating at cryogenic temperatures, they feature excellent energy resolution and low background. The detection of the possible light emitted when particles interact in the bolometer is a promising method to lower the background of the experiments. The different amount of light emitted in beta/gamma and alpha interactions, whether due to scintillation or Cerenkov emission, allows to discriminate the two interaction types. Because of the cryogenic environment, light detectors are often bolometers. I…
Random coincidence of 2ν2β decay events could be one of the main sources of background for 0ν2β decay in cryogenic bolometers due to their poor time resolution. Pulse-shape discrimination by using front edge analysis, the mean-time and \c{hi}2 methods was applied to discriminate randomly coinciding 2ν2β events in ZnMoO4 cryogenic scintillating bolometers. The background can be effectively rejected on the level of 99% by the mean-time analysis of heat signals with the rise time about 14 ms and the signal-to-noise ratio 900, and on the level of 98% for the light signals with 3 ms rise time and s…
Kinetic inductance bolometer (KIB) technology is a candidate for passive sub-millimeter wave and terahertz imaging systems. Its benefits include scalability into large 2D arrays and operation with intermediate cryogenics in the temperature range of 5 -- 10 K. We have previously demonstrated the scalability in terms of device fabrication, optics integration, and cryogenics. In this article, we address the last missing ingredient, the readout. The concept, serial addressed frequency excitation (SAFE), is an alternative to full frequency-division multiplexing at microwave frequencies conventional…
Random coincidence of events (particularly from two neutrino double beta decay) could be one of the main sources of background in the search for neutrinoless double beta decay with cryogenic bolometers due to their poor time resolution. Pulse-shape discrimination by using front edge analysis, mean-time and $χ^2$ methods was applied to discriminate randomly coinciding events in ZnMoO$_4$ cryogenic scintillating bolometers. These events can be effectively rejected at the level of 99% by the analysis of the heat signals with rise-time of about 14 ms and signal-to-noise ratio of 900, and at the le…
Searching for neutrinoless double-beta decay (0$ν$2$β$) is one of the main experimental challenges of modern physics. One experimental technique is given by cryogenic detectors named bolometers that are really promising for this purpose. The current generation tonne-scale experiment CUORE using this technology is putting the best limit on $^{130}$Te 0$ν$2$β$ half-life with TeO$_2$ crystals but its sensitivity is limited by its background. Therefore, it will be followed by the next generation experiment CUPID (CUORE Upgrade with Particle IDentification) that will study $^{100}$Mo embedded insid…
Bolometers are cryogenic calorimeters which feature excellent energy resolution, low energy threshold, high detection efficiency, flexibility in choice of materials, particle identification capability if operated as hybrid devices. After thirty years of rapid progresses, they represent nowadays a leading technology in several fields: particle and nuclear physics, X-ray astrophysics, cosmology. However, further and substantial developments are required to increase the sensitivity to the levels envisioned by future researches. A review of the challenges to be addressed and potentialities of bolo…
The CUPID-0 detector hosted at the Laboratori Nazionali del Gran Sasso, Italy, is the first large array of enriched scintillating cryogenic detectors for the investigation of $^{82}$Se neutrinoless double-beta decay (0$νββ$). CUPID-0 aims at measuring a background index in the region of interest (RoI) for 0$νββ$ at the level of 10$^{-3}$ c/keV/kg/y, the lowest value ever measured using cryogenic detectors. This result can be achieved by a state of the art technology for background suppression and thorough protocols and procedures for detector preparation and construction. In this paper, the di…
We have developed two analytical models to describe the performance of cryogenic microcalorimeters and bolometers. One of the models is suitable to describe Transition Edge Sensor (TES) detectors with an integrated absorber, the other is suitable for detectors with large absorbers. Both models take into account hot-electron decoupling and absorber decoupling. The differential equations describing these models have been solved using block diagram algebra. Each model has produced closed form solutions for the detector's responsivity, dynamic impedance, and noise equivalent power for phonon noise…
Next-generation experiments searching for neutrinoless double-beta decay must be sensitive to a Majorana neutrino mass as low as 10 meV. CUORE, an array of 988 TeO$_2$ bolometers being commissioned at Laboratori Nazionali del Gran Sasso in Italy, features an expected sensitivity of 50-130 meV at 90% C.L, that can be improved by removing the background from $α$ radioactivity. This is possible if, in coincidence with the heat release in a bolometer, the Cherenkov light emitted by the $β$ signal is detected. The amount of light detected is so far limited to only 100 eV, requiring low-noise cryoge…
The EDELWEISS collaboration aims for direct detection of light dark matter using germanium cryogenic detectors with low threshold phonon sensor technologies and efficient charge readout designs. We describe here the development of Ge bolometers equipped with high impedance thermistors based on a NbxSi1-x TES alloy. High aspect ratio spiral designs allow the TES impedance to match with JFET or HEMT front-end amplifiers. We detail the behavior of the superconducting transition properties of these sensors and the detector optimization in terms of sensitivity to out-of-equilibrium phonons. We repo…
For the first time, a cadmium tungstate crystal scintillator enriched in $^{116}$Cd has been succesfully tested as a scintillating bolometer. The measurement was performed above ground at a temperature of 18 mK. The crystal mass was 34.5 g and the enrichment level ~82 %. Despite a substantial pile-up effect due to above-ground operation, the detector demonstrated a high energy resolution (2-7 keV FWHM in 0.2-2.6 MeV $γ$ energy range), a powerful particle identification capability and a high level of internal radiopurity. These results prove that cadmium tungstate is an extremely promising dete…
We have developed and tested a new way of coupling bolometric light detectors to scintillating crystal bolometers based upon simply resting the light detector on the crystal surface, held in position only by gravity. This straightforward mounting results in three important improvements: (1) it decreases the amount of non-active materials needed to assemble the detector, (2) it substantially increases the light collection efficiency by minimizing the light losses induced by the mounting structure, and (3) it enhances the thermal signal induced in the light detector thanks to the extremely weak …
Direct detection of WIMP dark matter candidates has to face many difficult challenges. In particular, it requires an extremely high level of background rejection. The only way out seems to be particle identification which, for experiments based on nucleus recoil, is most efficiently performed by simultaneously detecting ionization or light and phonons. When comparing different approaches, it is necessary to keep in mind the potential requirement of building large detectors and the difficulties that this condition may raise for some cryogenic devices. It is claimed that the luminescent bolomete…
Bolometric detectors are excellent devices for the investigation of neutrinoless double-beta decay (0$νββ$). The observation of such decay would demonstrate the violation of lepton number, and at the same time it would necessarily imply that neutrinos have a Majorana character. The sensitivity of cryogenic detectors based on TeO$_2$ is strongly limited by the alpha background in the region of interest for the 0$νββ$ of $^{130}$Te. It has been demonstrated that particle discrimination in TeO$_2$ bolometers is possible measuring the Cherenkov light produced by particle interactions. However an e…
ZnMoO$_4$ scintillators with a mass of $\sim$ 0.3 kg, as well as Zn$^{100}$MoO$_4$ crystals enriched in the isotope $^{100}$Mo were produced for the first time by using the low-thermal-gradient Czochralski technique. The optical and luminescent properties of the produced crystals were studied to estimate the progress in crystal growth quality. The low-temperature tests with a 313 g ZnMoO$_4$ and two enriched Zn$^{100}$MoO$_4$ crystals were performed aboveground in the Centre de Sciences Nucléaires et de Sciences de la Matière. The low background measurements with a three ZnMoO$_4$ and two enri…
Electro-thermal coupling in semiconductor bolometers is known to create nonlinearities in transient detector response, particularly when such detectors are biased outside of their ideal regions (i.e. past the turnover point in their IV curves). This effect is further compounded in the case where a stray capacitance in the bias circuit is present, for example in long cryogenic cabling. We present a physical model of the influence of such electro-thermal coupling and stray capacitance in a composite NTD germanium bolometer, in which previous experimental data at high $V_{\rm bias}$ resulted in o…
We present the potential sensitivity of a future recoil detector for a first detection of the process of coherent elastic neutrino nucleus scattering (CE$ν$NS). We use the Chooz reactor complex in France as our luminous source of reactor neutrinos. Leveraging the ability to cleanly separate the rate correlated with the reactor thermal power against (uncorrelated) backgrounds, we show that a 10 kilogram cryogenic bolometric array with 100 eV threshold should be able to extract a CE$ν$NS signal within one year of running.
The Cryogenic Underground Observatory for Rare Events (CUORE) experiment at Gran Sasso National Laboratory of INFN searches for neutrinoless double beta decay using TeO2 crystals as cryogenic bolometers. The sensitivity of the measurement heavily depends on the energy resolution of the detector, therefore the success of the experiment stands on the capability to provide an extremely low noise environment. One of the most relevant sources of noise are the mechanical vibrations induced by the five Pulse Tube cryocoolers used on the cryogenic system which houses the detectors. To address this pro…
Random coincidences of nuclear events can be one of the main background sources in low-temperature calorimetric experiments looking for neutrinoless double-beta decay, especially in those searches based on scintillating bolometers embedding the promising double-beta candidate $^{100}$Mo, because of the relatively short half-life of the two-neutrino double-beta decay of this nucleus. We show in this work that randomly coinciding events of the two-neutrino double decay of $^{100}$Mo in enriched Li$_2$$^{100}$MoO$_4$ detectors can be effectively discriminated by pulse-shape analysis in the light …
Optimized filtering for pulse-shape based pile-up rejection applied to $0νββ$ search with $^{100}$Mo
CEA-IRFU（法国原子能和替代能源委员会研究核物理研究所）；IJCLab（巴黎萨克雷大学伊夫林实验室）；INFN-Milano（意大利国家核物理学院米兰分部）；Université Paris-Saclay（巴黎萨克雷大学）；CNRS/IN2P3（法国国家科学研究中心/法国国家粒子物理研究所）；Università di Milano-Bicocca（米兰比可卡大学）
Simulations of photon propagation in scintillation detectors were performed with the aim to find the optimal scintillator geometry, surface treatment, and shape of external reflector in order to achieve maximum light collection efficiency for detector configurations that avoid direct optical coupling, a situation that is commonly found in cryogenic scintillating bolometers in experimental searches for double beta decay and dark matter. To evaluate the light collection efficiency of various geometrical configurations we used the ZEMAX ray-tracing software. It was found that scintillators in the…
High light collection efficiency is an important requirement in any application of scintillation detectors. The purpose of this study is to investigate the possibility for improving this parameter in cryogenic scintillation bolometers, which can be considered as a promising detectors in experiments investigating neutrinoless double beta decay and dark matter. Energy resolutions and relative pulse amplitudes of scintillation detectors using ZnWO4 scintillation crystals of different shapes (cylinder 20 mm in dimater by 20 mm and hexagonal prism with diagonal 20 mm and height 20 mm), reflector ma…
CUORE Data Release for ML Applications: Pulse Shape Analysis Dataset
University of South Carolina（南卡罗来纳大学）；Virginia Polytechnic Institute and State University（弗吉尼亚理工大学）；INFN – Laboratori Nazionali di Legnaro（意大利国家核物理研究所-莱尼亚罗国家实验室）；INFN – Sezione di Bologna（意大利国家核物理研究所-博洛尼部分部）；Sapienza Università di Roma（罗马大学）；INFN – Sezione di Roma（意大利国家核物理研究所-罗马部分部）；Gran Sasso Science Institute（格兰萨索科学研究所）；INFN – Laboratori Nazionali del Gran Sasso（意大利国家核物理研究所-格兰萨索国家实验室）；University of California, Berkeley（加州大学伯克利分校）；INFN – Sezione di Milano Bicocca（意大利国家核物理研究所-米兰比可卡部分部）；Università degli Studi di Milano-Bicocca（米兰比可卡大学）
Bolometric detectors are used in particle physics experiments to search for rare processes, such as neutrinoless double beta decay and dark matter interactions. By operating at cryogenic temperatures, they are able to detect particle energies from a few keV up to several MeV, measuring the temperature rise produced by the energy released. This work focusses on the bolometers of the CUORE experiment, which are made of TeO$_2$ crystals. The response of these detectors is nonlinear with energy and changes with the operating temperature. The noise depends on the working conditions and significantl…
The cryogenic detectors in the form of bolometers are presently used for different applications, in particular for very rare or hypothetical events associated with new forms of matter, specifically related to the existence of Dark Matter. In the detection of particles with a semiconductor as target and detector, usually two signals are measured: ionization and heat. The amplification of the thermal signal is obtained with the prescriptions from Luke-Neganov effect. The energy deposited in the semiconductor lattice as stable defects in the form of Frenkel pairs at cryogenic temperatures, follow…
The CALDER project aims at developing cryogenic light detectors with high sensitivity to UV and visible light, to be used for particle tagging in massive bolometers. Indeed the sensitivity of CUORE can be increased by a factor of 3, thanks to the reduction of the $α$-background, obtained by detecting the Cherenkov light (100 eV) emitted by $β/γ$ events. Currently used light detectors have not the features required to address this task, so we decided to develop a new light detector using Kinetic Inductance Detector as a sensor. This approach is very challenging and requires an intensive R$\&$D …
Two neutrino double $β$ decay can create irremovable background even in high energy resolution detectors searching for neutrinoless double $β$ decay due to random coincidence of $2\nu2β$ events in case of poor time resolution. Possibilities to suppress this background in cryogenic scintillating bolometers are discussed. It is shown that the present bolometric detector technologies enable to control this form of background at the level required to explore the inverted hierarchy of the neutrino mass pattern, including the case of bolometers searching for the neutrinoless double $β$ decay of $^{1…
In the present work, we describe the results obtained with a large ($\approx 133$ cm$^3$) TeO$_2$ bolometer, with a view to a search for neutrinoless double-beta decay ($0νββ$) of $^{130}$Te. We demonstrate an efficient $α$ particle discrimination (99.9\%) with a high acceptance of the $0νββ$ signal (about 96\%), expected at $\approx 2.5$ MeV. This unprecedented result was possible thanks to the superior performance (10 eV rms baseline noise) of a Neganov-Luke-assisted germanium bolometer used to detect a tiny (70 eV) light signal from the TeO$_2$ detector, dominated by $γ$($β$)-induced Cheren…
A search for resonant absorption of solar axions by $^{169}$Tm nuclei was carried out. A newly developed approach involving low-background cryogenic bolometer based on Tm$_3$Al$_5$O$_{12}$ crystal was used that allowed for significant improvement of sensitivity in comparison with previous $^{169}$Tm based experiments. The measurements performed with $8.18$ g crystal during $6.6$ days exposure yielded the following limits on axion couplings: $|g_{Aγ} (g_{AN}^0 + g_{AN}^3) \leq 1.44 \times 10^{-14}$ GeV$^{-1}$ and $|g_{Ae} (g_{AN}^0 + g_{AN}^3) \leq 2.81 \times 10^{-16}$.
A scintillating bolometer based on a large cubic Li$_{2}$$^{100}$MoO$_4$ crystal (45 mm side) and a Ge wafer (scintillation detector) has been operated in the CROSS cryogenic facility at the Canfranc underground laboratory in Spain. The dual-readout detector is a prototype of the technology that will be used in the next-generation $0\nu2β$ experiment CUPID. The measurements were performed at 18 and 12 mK temperature in a pulse tube dilution refrigerator. This setup utilizes the same technology as the CUORE cryostat that will host CUPID and so represents an accurate estimation of the expected p…
CUORE - the Cryogenic Underground Observatory for Rare Events - is an experiment searching for the neutrinoless double-beta ($0νββ$) decay of $^{130}$Te with an array of 988 TeO$_2$ crystals operated as bolometers at $\sim$10 mK in a large dilution refrigerator. With this detector, we aim for a $^{130}$Te $0νββ$ decay half-life sensitivity of $9\times10^{25}$ y with 5 y of live time, and a background index of $\lesssim 10^{-2}$ counts/keV/kg/y. Making an effort to maintain radiopurity by minimizing the bolometers' exposure to radon gas during their installation in the cryostat, we perform all …
Li$_2$$^{100\textrm{depl}}$MoO$_4$ Scintillating Bolometers for Rare-Event Search Experiments
National Research Centre Kurchatov Institute（库尔恰托夫国家研究中心研究所）；Nikolaev Institute of Inorganic Chemistry（尼古拉耶夫无机化学研究所）；Universidad Internacional de La Rioja（拉里奥哈国际大学）；INFN, Sezione di Milano Bicocca（意大利国家核物理研究院米兰比科卡分部）；INFN, Sezione di Roma（意大利国家核物理研究院罗马分部）；Institute for Nuclear Research of NASU（乌克兰国家科学院核物理研究所）；INFN Sezione di Roma Tor Vergata（意大利国家核物理研究院罗马托尔维尔加塔分部）；INFN, Laboratori Nazionali del Gran Sasso（意大利国家核物理研究院格兰萨索国家实验室）
The Cryogenic Underground Observatory for Rare Events (CUORE) is an experiment to search for neutrinoless double beta decay ($0νββ$) in $^{130}$Te and other rare processes. CUORE is a cryogenic detector composed of 988 TeO$_2$ bolometers for a total mass of about 741 kg. The detector is being constructed at the Laboratori Nazionali del Gran Sasso, Italy, where it will start taking data in 2015. If the target background of 0.01 counts/(keV$\cdot$kg$\cdot$y) will be reached, in five years of data taking CUORE will have an half life sensitivity around $1\times 10^{26}$ y at 90\% C.L. As a first s…
Molybdenum based crystals such as Li$_2$MoO$_4$ and CaMoO$_4$ are emerging as leading candidates for next generation experiments searching for neutrino-less double beta decay with cryogenic calorimeters (CUPID, AMoRE). The exquisite energy resolution and high radio-purity of these crystals come at the cost of a potentially detrimental background source: the two neutrinos double beta decay of $^{100}$Mo. Indeed, the fast half-life of this decay mode, combined with the slow response of cryogenic calorimeters, would result in pile-up events in the energy region of interest for neutrino-less doubl…
In prospect of its application in cryogenic rare-event searches, we have investigated the low-temperature scintillation properties of CaWO4 crystals down to 3.4 K under α and γ excitation. Concerning the scintillation decay times, we observe a long component in the ms range which significantly contributes to the light yield below 40K. For the first time we have measured the temperature dependence of the α/γ- ratio of the light yield. This parameter which can be used to discriminate α and γ events in scintillating bolometers is found to be about 8-15% smaller at low temperatures compared to roo…
Near-equilibrium thermal detectors operate as classical calorimeters, with energy deposition and internal equilibration times short compared to the thermal time constant of the device. Advances in fabrication techniques, cryogenics, and electronics have made it practical to measure deposited energy with unprecedented sensitivity and precision. In this chapter we discuss performance considerations for these devices, including optimal filtering and energy resolution calculations. We begin with the basic theory of simple equilibrium calorimeters with ideal resistive thermometers. This provides a …
Neutrinoless double beta ($0νββ$) decay is a hypothetical rare nuclear transition ($T_{1/2}>10^{26}$ y). Its observation would provide an important insight about the nature of neutrinos (Dirac or Majorana particle) demonstrating that the lepton number is not conserved. This decay can be investigated with bolometers embedding the double beta decay isotope ($^{76}$Ge, $^{82}$Se, $^{100}$Mo, $^{116}$Cd, $^{130}$Te...), which perform as low temperature calorimeters (10 mK) detecting particle interactions via a small temperature rise read out by a dedicated thermometer. CROSS (Cryogenic Rare-event …
High-bandwidth frequency domain multiplexed readout of transition-edge sensors for neutrinoless double beta decay searches
McGill University（麦吉尔大学）；Lawrence Berkeley National Laboratory（劳伦斯伯克利国家实验室）；University of California Berkeley（加州大学伯克利分校）；Virginia Polytechnic Institute and State University（弗吉尼亚理工大学）；Massachusetts Institute of Technology（麻省理工学院）；Argonne National Laboratory（阿贡国家实验室）
