100 Collaboration, H. Prihtiadi, G. Adhikari, P. Adhikari, E. Barbosa de Souza, N. Carlin, S. Choi, W. Q. Choi, M. Djamal, A. C. Ezeribe, C. Ha, I. S. Hahn, A. … 展开作者
100 Collaboration, H. Prihtiadi, G. Adhikari, P. Adhikari, E. Barbosa de Souza, N. Carlin, S. Choi, W. Q. Choi, M. Djamal, A. C. Ezeribe, C. Ha, I. S. Hahn, A. J. F. Hubbard, E. J. Jeon, J. H. Jo, H. W. Joo, W. Kang, W. G. Kang, M. Kauer, B. H. Kim, H. Kim, H. J. Kim, K. W. Kim, N. Y. Kim, S. K. Kim, Y. D. Kim, Y. H. Kim, V. A. Kudryavtsev, H. S. Lee, J. Lee, J. Y. Lee, M. H. Lee, D. S. Leonard, K. E. Lim, W. A. Lynch, R. H. Maruyama, F. Mouton, S. L. Olsen, H. K. Park, H. S. Park, J. S. Park, K. S. Park, W. Pettus, Z. P. Pierpoint, S. Ra, F. R. Rogers, C. Rott, A. Scarff, N. J. C. Spooner, W. G. Thompson, L. Yang, S. H. Yong
The COSINE-100 dark matter search experiment has started taking physics data with the goal of performing an independent measurement of the annual modulation signal observed by DAMA/LIBRA. A muon detector was constructed by using plastic scintillator panels in the outermost layer of the shield surrounding the COSINE-100 detector. It is used to detect cosmic ray muons in order to understand the impact of the muon annual modulation on dark matter analysis. Assembly and initial performance test of each module have been performed at a ground laboratory. The installation of the detector in Yangyang Underground Laboratory (Y2L) was completed in the summer of 2016. Using three months of data, the muon underground flux was measured to be 328 $\pm$ 1(stat.)$\pm$ 10(syst.) muons/m$^2$/day. In this report, the assembly of the muon detector and the results from the analysis are presented.
We report measurements of annual and diurnal modulations of the cosmic-ray muon rate in the Yangyang underground laboratory (Y2L) using 952 days of COSINE-100 data acquired between September 2016 and July 2019. A correlation of the muon rate with the atmospheric temperature is observed and its amplitude on the muon rate is determined. The effective atmospheric temperature and muon rate variations are positively correlated with a measured effective temperature coefficient of $α_{T}$ = 0.80 $\pm$ 0.11. This result is consistent with a model of meson production in the atmosphere. We also searched…
COSINE-100 is a dark matter direct detection experiment designed to test the annual modulation signal observed by the DAMA/LIBRA experiment. COSINE-100 consists of 8 NaI(Tl) crystals with a total mass of 106 kg, a 2200 L liquid scintillator veto, and 37 muon detector panels. We present details of the data acquisition system of COSINE-100, including waveform storage using flash analog-to-digital converters for crystal events and integrated charge storage using charge-sensitive analog-to-digital converters for liquid scintillator and plastic scintillator muon veto events. We also discuss several…
The annual modulation signal observed by the DAMA experiment is a long-standing question in the community of dark matter direct detection. This necessitates an independent verification of its existence using the same detection technique. The COSINE-100 experiment has been operating with 106~kg of low-background NaI(Tl) detectors providing interesting checks on the DAMA signal. However, due to higher backgrounds in the NaI(Tl) crystals used in COSINE-100 relative to those used for DAMA, it was difficult to reach final conclusions. Since the start of COSINE-100 data taking in 2016, we also have …
The COSINE-100 experiment has been operating with 106 kg of low-background NaI(Tl) detectors to test the results from the DAMA/LIBRA experiment, which claims to have observed dark matter. However, since the background of the NaI(Tl) crystals used in the COSINE-100 experiment is 2-3 times higher than that in the DAMA detectors, no conclusion regarding the claimed observation from the DAMA/LIBRA experiment could be reached. Therefore, we plan to upgrade the current COSINE-100 experiment to the next phase, COSINE-200, by using ultra-low background NaI(Tl) detectors. The basic principle was alread…
A monitoring system for fast neutrons is planned in the COSINE experiment, a dark matter experiment with NaI crystals. We pursued several R&D approaches for a neutron detector using a liquid scintillator (LS). A pulse shape discrimination (PSD) technique is used for the identification of neutron events and the PSD properties of two different LS were compared. A good separation power between neutrons and $γ$ has been achieved for energies between 200 keVee to 1500 keVee. The combination of alumina adsorption, filtration, and water extraction is effective in purifying the LS, which leads to a re…
The SoLid detector was constructed during 2017 and started to take data in December 2017. Commissioning a new detector implies defining and understanding a whole set of new variables. On the one hand the environmental conditions are followed, and on the other hand quantities related to the stability of the detector are monitored. Cosmic muons are ideal for studying the stability of SoLid, because of their abundance due to the small overburden. Muons can be used to study the timing synchronisation and energy calibration of the detector on a daily timescale. They can be used to monitor the detec…
The motivation for a cosmic muon veto (CMV) detector is to explore the possibility of locating the proposed large Iron Calorimeter (ICAL) detector at the India based Neutrino Observatory (INO) at a shallow depth. An initial effort in that direction, through the assembly and testing of a $\sim$ 1 m $\times$ 1 m $\times$ 0.3 m plastic scintillator based detector, is described. The plan for making a CMV detector for a smaller prototype mini-ICAL is also outlined.
In the case of underground experiments for neutrino physics or rare event searches, the background caused by cosmic muons contributes significantly and therefore must be identified and rejected. We proposed and optimized a new detector using liquid scintillator with wavelenghth-shifting fibers which can be employed as a veto detector for cosmic muons background rejection. From the prototype study, it has been found that the detector has good performances and is capable of discriminating between muons induced signals and environmental radiation background. Its muons detection efficiency is grea…
The CMS muon detector system, muon reconstruction software, and high-level trigger underwent significant changes in 2013-2014 in preparation for running at higher LHC collision energy and instantaneous luminosity. The performance of the modified system is studied using proton-proton collision data at center-of-mass energy $\sqrt{s}=$ 13 TeV, collected at the LHC in 2015 and 2016. The measured performance parameters, including spatial resolution, efficiency, and timing, are found to meet all design specifications and are well reproduced by simulation. Despite the more challenging running condit…
The goals of the ongoing and planned ATLAS muon detector upgrades are to increase the acceptance for precision muon momentum measurement and triggering and to improve the rate capability of the muon chambers in the high-background regions corresponding to the increasing LHC luminosity. Smalldiameter Muon Drift Tube (sMDT) chambers have been developed for these purposes. With half the drift-tube diameter of the current ATLAS Muon Drift Tube (MDT) chambers with 30 mm drift tube diameter and otherwise unchanged operating parameters, the sMDT chambers share all the advantages of the MDTs, but have…
The Iron Calorimeter (ICAL) detector at the India based Neutrino Observatory (INO) is planned to be set up in an underground cavern with a rock overburden of more than 1 km. This overburden reduces the cosmic muon flux by a factor of 10$^{6}$ with respect to that at sea level. In this paper, we examine the possibility of a 100 m shallow depth ICAL (SICAL) detector. The cosmic muons would have to be detected in a veto detector surrounding ICAL with an efficiency of 99.99 % in order to have the same level of muon background leaking undetected through the veto detector as at the 1 km depth underg…
The Monitored Drift Tubes, as a part of the ATLAS muon spectrometer, are precision drift chambers designed to provide excellent spatial resolution and high tracking efficiency independent of the track angle. Through the life of the LHC and ATLAS experiment, this detector has already demonstrated that they provide precise tracking over large areas. The aim of the ATLAS muon spectrometer upgrade is to increase the muon trigger efficiency, precise muon momentum measurement and to improve the rate capability of the muon system in the high-background regions during the High-Luminosity LHC runs. To …
Muon Telescope Detector (MTD) is a newly installed detector in the STAR experiment. It provides an excellent opportunity to study heavy quarkonium physics using the dimuon channel in heavy ion collisions. In this paper, we report the muon identification performance for the MTD using proton-proton collision at $\sqrt{s}$ = 500 GeV with various methods. The result using the Likelihood Ratio method shows that the muon identification efficiency can reach to $\sim$90% for muons with transverse momentum greater than 3 GeV/c and the significance of J/$ψ$ signal is improved by $\sim$40% compared to us…
A set of classical multi-wire proportional chambers were designed and constructed with the main purpose of efficient cosmic muon detection. These detectors are relatively simple to construct, and at the same time are low cost, making them ideal for educational purposes. The detector layers have efficiencies above 99% for minimum ionizing cosmic muons, and their position resolution is about 1 cm, that is, particle trajectories are clearly observable. Visualization of straight tracks is possible using an LED array, with the discriminated and latched signal driving the display. Due to the excepti…
Cosmic ray muons present a large part of the radiation background and depending on the application of interest muons can be seen as background noise, e.g., radiation mapping, radiation protection, dosimetry, or as a useful interrogation probe such as cosmic ray muon tomography. It is worth noting recent developments on muon scattering tomography which has emerged as a prospective noninvasive monitoring method for many applications including spent nuclear fuel cask monitoring and geotomography. However, it is still very challenging to measure muon momentum in the field, despite the apparent ben…
The Jiangmen Underground Neutrino Observatory (JUNO) is a multi-purpose neutrino experiment. One of the main goals is to determine the neutrino mass ordering by precisely measuring the energy spectrum of reactor antineutrinos. For reactor antineutrino detection, cosmogenic backgrounds such as $^9$Li/$^8$He and fast neutrons induced by cosmic muons should be rejected carefully by applying muon veto cuts, which requires good muon track reconstruction. With a 20~kton liquid scintillator detector, simulation shows the proportion of muon bundles to be around 8\% in the JUNO, while its reconstructio…
The underground muon detector of the Pierre Auger Observatory is aimed at attaining direct measurements of the muonic component of extensive air showers produced by cosmic rays with energy from $10^{16.5}$ eV up to the region of the ankle (around $10^{18.7}$ eV). It consists of two nested triangular grids of underground scintillators with 433 m, and 750 m spacings and a total of 71 positions, each with 192 scintillator strips (30 m$^2$) deployed 2.3 m underground. The light produced by impinging muons in the scintillators is propagated with optical fibers towards an array of silicon photomulti…
A broken lepton family symmetry can lead to muon decay to a Familon \[μ\to {χ_{Familon}} + e .\] We propose to search for two body muon decay to a Familon in the mass range from 86 to 105 MeV/c$^2$, by observing stopped positive muons. This mass region is the search window blind spot of magnetic spectrometers. The search signal will be a mono-energetic positron peak on top of the standard model muon Michel decay spectrum. The decay positron spectrum will be measured in HPGe detectors surrounded by large volume NaI detectors and a charged particle tracking system used to help reduce false trigg…
High-energy muons generated from cosmic-ray particle showers have been shown to exhibit properties ideal for imaging the interior of large structures. This paper explores the possibility of using a single portable muon detector in conjunction with image reconstruction methods used in nuclear medicine to reconstruct a 3D image of the interior of critical infrastructure such as the Zero Energy Deuterium (ZED-2) research reactor at Canadian Nuclear Laboratories' Chalk River site. The ZED-2 reactor core and muon detector arrangement are modeled in GEANT4 and Monte Carlo measurements of the resulta…
A tracking detector system has been constructed with an innovative approach to the classical multi-wire proportional chamber concept, using contemporary technologies. The detectors, covering an area of 0.58 square meters each, are optimized for the application of muon radiography. The main features are high (>99.5%) and uniform detection efficiency, 9 mm FWHM position resolution, filling gas consumption below 2 liters per hour for the non toxic, non flammable argon and carbon dioxide mixture. These parameters, along with the simplicity of the construction and the tolerance for mechanical effec…
The Fermilab Muon $g-2$ experiment is currently preparing for its fourth data-taking period (Run-4). The experiment-wide effort on the analysis of Run-1 data is nearing completion, with the announcement of the first result expected in the coming months. The final goal of the experiment is to determine the muon magnetic anomaly to a precision of 140 ppb. This level of precision will provide indirect evidence of new physics, if the central value agrees with the previously-measured value of the magnetic anomaly. Essential in reducing the systematic uncertainty, through measurements of the muon be…
The ATLAS experiment at the Large Hadron Collider (LHC) employs a trigger system consisting of a first-level hardware trigger (L1) and a software-based high-level trigger. The L1 muon trigger system selects muon candidates, assigns them to the correct LHC bunch crossing and classifies them into one of six transverse-momentum threshold classes. The L1 muon trigger system uses resistive-plate chambers (RPCs) to generate the muon-induced trigger signals in the central (barrel) region of the ATLAS detector. The ATLAS RPCs are arranged in six concentric layers and operate in a toroidal magnetic fie…
Small-diameter muon drift tube (sMDT) chambers with 15 mm tube diameter are a cost-effective technology for high-precision muon tracking over large areas at high background rates as expected at future high-energy hadron colliders including HL-LHC. The chamber design and construction procedures have been optimized for mass production and provide sense wire positioning accuracy of better than 10 ?m. The rate capability of the sMDT chambers has been extensively tested at the CERN Gamma Irradiation Facility. It exceeds the one of the ATLAS muon drift tube (MDT) chambers, which are operated at unpr…
The $g-2$ experiment successfully completed its second data taking period (Run-2) between March and July 2019, with the analysis of Run-1 and Run-2 data currently proceeding. The final goal of the experiment is to determine the muon magnetic anomaly, $a_μ=\frac{g-2}{2}$, to a precision of 140 ppb. Essential to reducing the systematic uncertainty on $a_μ$ through measurements of the muon beam profile are the in-vacuum straw tracking detectors. A crucial prerequisite to obtaining accurate distributions of the beam profile is the internal alignment of the trackers, which is described here, along …
We report a measurement of muon annual modulation in a 12-liter liquid scintillation detector with a live-time of more than 4 years at the Soudan Underground Laboratory. Muon minimum ionization in the detector is identified by its observed pulse shape and large energy deposition. The measured muon rate in the detector is 28.69$\pm$2.09 muons per day with a modulation amplitude of 2.66$\pm$ 1.0\% and a phase at Jul 22 $\pm$ 36.2 days. This annual modulation is correlated with the variation of the effective atmospheric temperature in the stratosphere. The correlation coefficient, $α_{T}$, is det…
The CosmicWatch Desktop Muon Detector is a Massachusetts Institute of Technology (MIT) and Polish National Centre for Nuclear Research (NCBJ) based undergraduate-level physics project that incorporates various aspects of electronics-shop technical development. The detector was designed to be low-power and extremely portable, which opens up a wide range of physics for students to explore. This document describes the physics behind the Desktop Muon Detectors and explores possible measurements that can be made with the detectors. In particular, we explore various physical phenomena associated wit…
COSINE-200 is the next phase of the ongoing COSINE-100 experiment. The main purpose of the experiment is the performance of an unambiguous verification of the annual modulation signals observed by the DAMA experiment. The success of the experiment critically depends on the production of a 200 kg array of ultra-pure NaI(Tl) crystal detectors that have lower backgrounds than the DAMA crystals. The purification of raw powder is the initial but important step toward the production of ultra-pure NaI(Tl) detectors. We have already demonstrated that fractional recrystallization from water solutions i…
The CMS muon system at the LHC is built of different detector technologies. The measurement of the background hit rates in the different muon detectors during the LHC Run-2 is of prime importance for an assessment of the longevity of the chambers and their on-board electronics, and therefore for the expected performance of the system at HL-LHC. Moreover, an accurate modelling of the backgrounds using simulations is also critical, as an estimation of the expected radiation background for the Phase-2 upgrade can only rely on Montecarlo-based predictions in the regions where new detectors are bei…
Large liquid argon TPC detector programs such as LBNE and LAGUNA-LBNO will be able to make measurements of the proton lifetime which will outperform Cherenkov detectors in the proton decay channel $p \rightarrow K^{+}ν$. At the large depths which are proposed for such experiments, a non-negligible source of isolated charged kaons may be produced in the showers of cosmogenic muons. We present an estimate of the cosmogenic muon background to proton decay in the $p \rightarrow K^{+}ν$ channel. The simulation of muon transport to a depth of 4 km w.e, is performed in the MUSIC framework and the pro…
Validation of the COSINE-100U NaI(Tl) Encapsulation for Low-Temperature Operation in Liquid Scintillator
Institute for Basic Science (IBS)(基础科学研究院);Chung-Ang University(中央大学);University of Science and Technology (UST)(科学技术大学);Jeju National University(济州国立大学);Kyungpook National University(庆北国立大学)
Since the end of Run 1 of the LHC in 2012, the outermost ring has been added to the CMS Cathode Strip Chambers (CSC) endcap muon detector, and the readout electronics of the innermost ring of CSCs have been upgraded to accommodate the larger luminosity and collision energy anticipated in Run 2. A major effort was required to build, install, and commission these new chambers and electronics. This talk summarizes the improvements made during this upgrade and presents the performance of the CSC detector during the early stages of Run 2.
The charge ratio ${k \equiv μ^+/μ^-}$ for atmospheric muons has been measured using Large Volume Detector (LVD) in the INFN Gran Sasso National Laboratory, Italy (minimal depth is 3000 m w.e.). To reach this depth muons should have the energy at the sea level greater than 1.3 TeV. The muon charge ratio was defined using the number of the decays of stopping positive muons in the LVD iron structure and the decays of positive and negative muons in scintillator. We have obtained the value of the muon charge ratio ${k}$ ${= 1.26 \pm 0.04(stat) \pm 0.11(sys)}$.
The muon detectors of the experiments at the Large Hadron Collider (LHC) have to cope with unprecedentedly high neutron and gamma ray background rates. In the forward regions of the muon spectrometer of the ATLAS detector, for instance, counting rates of 1.7 kHz/square cm are reached at the LHC design luminosity. For high-luminosity upgrades of the LHC, up to 10 times higher background rates are expected which require replacement of the muon chambers in the critical detector regions. Tests at the CERN Gamma Irradiation Facility showed that drift-tube detectors with 15 mm diameter aluminum tube…
The Muon Ionization Cooling Experiment (MICE) will perform a detailed study of ionization cooling to evaluate the feasibility of the technique. To carry out this program, MICE requires all of its detectors to reconstruct space points in a globally consistent fashion. The beam-based alignment constants were found to be more accurate than the survey for the scintillating-fibre trackers lodged inside the bores of the superconducting magnets. This alignment algorithm can achieve unbiased measurements of the trackers rotation angles with a resolution of 6 mrad/$\sqrt{N}$ and of their position with …
LHAASO KM2A consists of 5915 scintillation detectors and 1188 muon detectors, and the muon detectors cover 4% area of the whole array with 30 m spacing. The muon number of air shower events, with very high energy, is investigated with the data recorded by muon detector of the 3/4 LHAASO array in 2021. The attenuation length of muon number in the air shower is measured by fitting the muon number with constant flux in various zenith angles, based on the constant intensity cut method. The variation of the attenuation length as shower energy from hundreds TeV to tens PeV is presented. The results …
Cosmic ray muon has strong penetrating power and no ionizing radiation hazards, which makes it an ideal probe for detecting special nuclear materials. In this paper, a high spatial resolution muon tomography system based on Micromegas detectors is proposed to optimize the imaging time and quality. The proposed system includes eight Micromegas detectors based on the thermal bonding technique and a scalable readout system. In addition, a multiplexing method based on position encoding is developed to reduce the number of electronics channels by order of magnitude. The spatial resolution of the pr…
The NO$ν$A collaboration has constructed a 14,000 ton, fine-grained, low-Z, total absorption tracking calorimeter at an off-axis angle to an upgraded NuMI neutrino beam. This detector, with its excellent granularity and energy resolution and relatively low-energy neutrino thresholds, was designed to observe electron neutrino appearance in a muon neutrino beam, but it also has unique capabilities suitable for more exotic efforts. In fact, if an efficient upward-going muon trigger with sufficient cosmic ray background rejection can be demonstrated, NO$ν$A will be capable of a competitive indirec…
We utilise muons from cosmic ray to explore hidden underground archaeological structures. Presented here is the design, simulation studies and first laboratory results of a compact, scintillators based, cosmic ray muon telescope for underground muon radiography.
A method is described which allows to deduce the dead-time of the front-end electronics of the LHCb muon detector from a series of measurements performed at different luminosities at a bunch-crossing rate of 20 MHz. The measured values of the dead-time range from 70 ns to 100 ns. These results allow to estimate the performance of the muon detector at the future bunch-crossing rate of 40 MHz and at higher luminosity.