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This article discusses the problem of selection by modeling the optimal parameters of a new scintillation muon hodoscope created for the development of the muonography method. The muon hodoscope is a scintillation detector consisting of several layers of scintillation strips with fiber optic light collection on silicon photomultipliers (SiPM). Its exact model in the Geant4 software package was developed. With its help, the passage of muons through the detector and the response of the detector to these events are simulated. The reconstruction of the tracks of muons was carried out and the accuracy of their reconstruction was estimated. The obtained distributions of events in the angle between the reconstructed and "real" tracks for various detector parameters and the selection of optimal parameters for the highest accuracy and efficiency of the reconstruction of muon tracks are considered.

This work reports a cost-effective, simple front-end readout and DAQ of a RPC-based muon scattering tomography system under construction. The Time-over-threshold property of NINO ASICs has been exploited to achieve precise tracking by extraction of position information. The use of a low-cost FPGA for event selection and TOT measurement has been demonstrated for a prototype RPC which has been triggered by a cosmic ray hodoscope of three plastic scintillators. The relation between input pulse width and TOT has been established by analyzing the waveforms of the RPC signals. The TOT profile at different working voltages has been obtained by the FPGA and it has been fitted with the Gaussian distribution. Its standard deviation represents an estimate of the tracking precision.

The restart of the Transient Reactor Test Facility (TREAT) at Idaho National Laboratory and consequent refurbishment of the Fuel Motion Monitoring System (FMMS), or Hodoscope, offers the opportunity to upgrade the detector system used for neutron imaging. Silicon photomultipliers (SiPMs) are a viable option for updating the Hodoscope to yield improved fuel monitoring capability. The Hodoscope uses ZnS(Ag) proton recoil scintillators (PRS) that provide good gamma-ray suppression and discrimination. Previous work showed that the Hamamatsu S13360-6075CS SiPM offers the best neutron detection and gamma-ray discrimination capability with the ZnS PRS. This work optimizes a SiPM-based detector and develops a PRS prototype for testing. Specifically, possible overvoltages for use are determined by confirming steady operation over extended measurement times. In addition, various SiPM-circuit implementations are tested to optimize the detector according to desired properties, and ultimately a PRS prototype is developed with modifiable components for versatile testing. Measurements of the neutron detection efficiency and gamma-ray rejection efficiency of SiPM-based PRS detectors and a reference PMT-based detector are also carried out. Neutron detection efficiency ranges between 1–2%, and detected gamma-ray rejection efficiency is on the order of 10−7. Use of a low-pass filter only or a low-pass filter and 50-ω shunt resistor is recommended for the SiPM-based detector, and both configurations demonstrate improved performance over the PMT-based detector.

The NA62 experiment is a fixed-target experiment at CERN SPS. The main goal of the experiment is to measure the branching ratio of the ultra-rare kaon decay $K^{+}\to\pi^{+}\nu\bar\nu$. The NA62 detector allows also to study other rare kaon decays and to search for very weakly coupled particles of MeV-GeV mass-scale. The new ANTI-0 hodoscope is proposed and designed to veto events with charged halo particles entering the decay volume. It is now being assembled at CERN. The detector design, the performance simulation and the results of measurements with cosmic rays and test beams for the individual elements are presented. The commissioning and the first run of data-taking is scheduled for after the end of LS2 long shutdown (April 2021)., Comment: INSTR20: Instrumentation for Colliding Beam Physics

The observation of long-lived particles at the LHC would reveal physics beyond the Standard Model and could account for the many open issues in our understanding of our universe. Long-lived particle signatures are well motivated and can appear in many theoretical constructs that address the Hierarchy Problem, Dark Matter, Neutrino Masses and the Baryon Asymmetry of the Universe. With the current experiments at the particle accelerators, no search strategy will be able to observe the decay of neutral long-lived particles with masses above GeV and lifetimes at the limit set by Big Bang Nucleosynthesis, cτ ∼ 107–108 m. The MATHUSLA detector concept (MAssive Timing Hodoscope for Ultra-Stable neutraL pArticles) will be presented. It can be implemented on the surface above ATLAS or CMS detectors in time for the high-luminosity LHC operations, to search for neutral long-lived particles with lifetimes up to the BBN limit. The large area of the detector allows MATHUSLA to make important contributions also to cosmic-ray physics. We will also report on the analysis of data collected by the test stand installed on the surface above the ATLAS detector, the on-going background studies, and plans for the MATHUSLA detector. The observation of long-lived particles at the LHC would reveal physics beyond the Standard Model, could account for the many open issues in our understanding of our universe, and conceivably point to a more complete theory of the fundamental interactions. Such long-lived particle signatures are fundamentally motivated and can appear in virtually every theoretical construct that address the Hierarchy Problem, Dark Matter, Neutrino Masses and the Baryon Asymmetry of the Universe. We describe in this document a large detector, MATHUSLA, located on the surface above an HL-LHC $pp$ interaction point, that could observe long-lived particles with lifetimes up to the Big Bang Nucleosynthesis limit of 0.1 s. We also note that its large detector area allows MATHUSLA to make important contributions to cosmic ray physics. Because of the potential for making a major breakthrough in our conceptual understanding of the universe, long-lived particle searches should have the highest level of priority.

Modern nuclear physics experiments demand for new high-resolution and high-versatility detectors for the reconstruction of collision events. In this framework, we have developed a new hodoscope of silicon detectors for charged particles called OSCAR. This new device consists of individual modules with partially embedded electronics capable to identify low energy particles down to about 1 MeV/u. OSCAR is a particularly suitable detector to be used as a standalone detector or as ancillary system for large acceptance devices. This paper presents an overview of the layout and capabilities of the detector.

New forward hadron calorimeter with transverse and longitudinal segmentation has been developed and constructed for the upgraded fixed target BM@N experiment at JINR, Dubna. The main purpose of this calorimeter is to provide event-by-event centrality and reaction plane orientation measurements in nucleus-nucleus collisions. The design of the hadron calorimeter composed of sampling lead/scintillator modules with a beam hole in the center is discussed. The light collection from longitudinal sections in modules is provided by Wave Length Shifting (WLS) fibers embedded in scintillator plates. Micro-pixel photodetectors (Hamamatsu MPPCs) are used for light detection from each longitudinal section of modules. The measured light yield is about 50 photoelectrons per section for MIPs. Sampling ADCs are used for signal readout in the calorimeter. The performance of the FHCAL is discussed. For centrality measurement additional forward quartz hodoscope is developed to measure charge of fragments in the FHCAL beam hole. The method of collision centrality determination is discussed.

The method of two-dimensional filtering of modulated matrix data sequences is proposed. The structure of a two-dimensional filter based on operations of element-by-element matrix multiplications is developed. An application of the two-dimensional filtering of the URAGAN muon hodoscope matrix data sequence for the elimination of muon flux diurnal modulations is discussed.

The Barrel Time-of-Flight detector system will be installed in the upcoming ANDA experiment at FAIR in Germany. The detector has a barrel shape of =0.5 m and 1.8 m long, covering about 5 m2, which corresponds to the laboratory polar angle coverage of 22o

Currently m(2)-sized micropattern detectors with spatial resolution better than 100 mu m and online trigger capability are of big interest for many experiments. Large size in combination with superb spatial resolution and trigger capability implicates that the construction of these detectors is highly sophisticated and imposes strict mechanical tolerances. We developed a method to survey assembled and working detectors on potential deviations of the micro pattern readout structures from design value as well as deformations of the whole detector, using cosmic muons in a tracking facility. The LMU Cosmic Ray Facility consists of two 8m(2) ATLAS Monitored Drift Tube chambers (MDT) for precision muon reference tracking and two segmented trigger hodoscopes with sub-ns time-resolution and additional 10 cm position information along the wires of the MDTs. It provides information on homogeneity in efficiency and pulse height of one or several micropattern detectors installed in between the MDTs. With an angular acceptance of 30 to + 30 degrees the comparison of the reference muon tracking with centroidal position determination or time projection chamber like track reconstruction in the micropattern detector allows for calibration in three dimensions. We present results of a m(2)-sized one-dimensional resistive strip Micromegas detector consisting of two readout boards with in total 2048 strips, read out by 16 APV25 front-end boards. This 16-fold segmentation along the precision direction in combination with a 10-fold segmentation in orthogonal direction by the resolution of the trigger hodoscope, allows for very detailed analysis of the 1 m(2) detector under study by subdivision into 160 partitions, each being analyzed separately. We are able to disentangle deviations from the readout strip straightness and global deformation due to the small overpressure caused by the Ar: CO2 (93: 7) gas mixture flux. We introduce the alignment and calibration procedure, report on homogeneity in efficiency and pulse height and present results on deformation and performance of the m(2)-sized Micromegas.

Muon hodoscope URAGAN allows to obtain the angular distribution of the muon flux. This distribution may be characterized by a vector of local anisotropy (the sum of the vectors of the particle arrival directions, normalized to the total number of muons). It was shown that annual variations in the vertical projection of the anisotropy vector A Z are not related with changes in atmospheric conditions. The dependence of A Z on the index of the primary particles spectrum γ was calculated for several zenith angle intervals with the help of simulation of generation and propagation of secondary cosmic ray particles through the atmosphere using the CORSIKA package. Experimental temporal series of the vertical projection of the local anisotropy A Z for several intervals of zenith angles were obtained for 2007-2015. According to the obtained A Z time series, annual and diurnal changes of Δγ were estimated.

A hodoscope prototype to detect charged particles in the NA62 experiment at CERN SPS has been installed within the experimental setup in 2014 and exposed to the beam during the data taking period. Efficiency and time resolution for hodoscope tiles are measured. The average signal amplitude (proportional to the light yield) is estimated from the efficiency curves. The results of the tests have lead to several improvements in the final design of the hodoscope.

The new scintillation muon hodoscope to study cosmic ray muon flux variations was created in MEPhI. The basic characteristics of the hodoscope (sensitivity area, precision of the muon track reconstruction, 'live' time etc.) are comparable with other hodoscopes (TEMP and URAGAN) of MEPhI. Modular design is a distinctive feature of the detector, supplying relativity easy transportability, and low maintenance requirements give a possibility of a long-term autonomic operation. First results of the cosmic ray muon variation study by means of the scintillation muon hodoscope are presented and discussed.

The coronal mass ejection (CME) that occurred on April 28, 2015 is analyzed. The passage of the ejection did not cause geoeffective disturbances in the near-Earth space. At the same time, the CME had a significant impact on the flux of cosmic rays registered on the Earth's surface by the muon hodoscope URAGAN.

Results of the studies of cosmic ray muon flux variations during the powerful Forbush effect registered by the muon hodoscope URAGAN on June 22, 2015 are presented. From the muon flux angular distribution, the dependence of the intensity decrease amplitude on the primary particle energy in the region above 10 GeV has been obtained. The changes of this dependence at different phases of the Forbush effect development have been studied. Based on the analysis of spatial and angular variations of the muon flux, the values of the local anisotropy vector parameters, as well as unique muon snapshots (muonographies) have been obtained. The characteristics of the heliospheric and magnetospheric disturbances during the considered event have been analyzed.

Muon hodoscope URAGAN consists of four independent supermodules with total area 46 m2 and is under operation in the Experimental complex NEVOD (MEPhI, Moscow) from 2007. At present, the sequence of real-time data of angular variations of muon flux measured in the hodoscopic mode and also the results of their analysis: local angular anisotropy, wavelet frequencies, etc. are available at the URAGAN web-site. Some peculiarities of application of these data for the analysis of various events in heliosphere, magnetosphere and atmosphere are discussed.

The approach to the analysis of spatial-angular characteristics of the muon flux variations at different phases of Forbush decrease development according to the muon snapshots (muongraphies) obtained using muon hodoscope URAGAN, as well as the analysis results are presented.

The LHAASO project is to be built in south-west China, using an array of 5137 electron detectors for the measurement of incident electrons arriving at the detector plane. For quality control of the large number of electron detectors, a cosmic ray hodoscope with two-dimensional spatial sensitivity and good time resolution has been developed. The first prototype of the electron detector has been tested with the hodoscope and the performance of the detector is found to be consistent with the design.

The results of time resolution measurements on cosmic muons with MWPC chambers as a tracking system are presented. Two options of dual SiPM readout considered: direct light collection from opposite cut corners of the scintillator and light collection using two oppositely directed bundles of WLS fibers. Two types of SiPMs are used: S10985-050C and MicroFB-60035. The best result achived using mean-time between two SiPMs. For the direct readout from 134 × 107 × 20 mm3 scintillator time resolution σ = 300±10 ps and maximum signal arrival time spread ΔT = 1.6±0.2 ns. Using WLS fiber readout option with 265 × 107 × 30 mm3 scintillator tile signal arrival time spread ΔT = 150±50 ps and time resolution σ = 370±10 ps.

The Mu3e experiment searches for charged lepton flavor violation in the rare decay μ→eee. In order to reach a sensitivity of better than 10−16, more than 109 muon decays per second have to be observed over a running time of one year. Precise determination of particle momentum, vertex position and time are necessary for background suppression. These requirements can be met by combining an ultra-lightweight tracker based on High-Voltage Monolithic Active Pixel Sensors (HV-MAPS) with a timing system which consists of a scintillating fiber detector and a tile hodoscope. As the momentum of particles from muon decay at rest is below 53 MeV/c, the silicon pixel tracker resolution is dominated by multiple Coulomb scattering. This leads to extreme requirements for the material budget of the tracking detector of below 0.1% of a radiation length per layer. Even though the target power consumption of the HV-MAPS detector is as low as 150 mW/cm2, the detector cooling must be very efficient and at the same time avoid adding material inside the active tracking volume.

Muon diagnostics is a technique of remote monitoring of various dynamic processes in the heliosphere, the magnetosphere and the atmosphere of the Earth based on the analysis of spatial-angular and temporal variations of muon flux simultaneously detected from all directions of the upper hemisphere. The developed approaches to data analysis and results of the study of various terrestrial and extra-terrestrial processes detected by means of a wide aperture URAGAN muon hodoscope are discussed.

Intensity of the atmospheric muon flux depends on a number of factors: energy spectrum of primary cosmic rays (PCR), heliospheric conditions, state of the magnetosphere and atmosphere of the Earth. The wide-aperture muon hodoscope URAGAN (Moscow, Russia, 55.7° N, 37.7° E, 173 m a.s.l.) makes it possible to investigate not only variations of the intensity of muon flux, but also temporal changes of its angular distribution. For the analysis of angular distribution variations, the vector of local anisotropy is used. The vector of local anisotropy is the sum of individual vectors (directions of the reconstructed muon tracks) normalized to the total number of reconstructed tracks. The vector of local anisotropy and its projections show different sensitivities to parameters of the processes of modulation of PCR in the heliosphere and the Earth's magnetosphere, and the passage of secondary cosmic rays through the terrestrial atmosphere. In the work, results of the analysis of long-term variations of hourly average projections of the vector of local anisotropy obtained from the URAGAN data during experimental series of 2007-2011 are presented.

The features of the study of heliospheric disturbances on the basis of ground level cosmic ray muon flux observations are discussed. The muon hodoscope URAGAN simultaneously detects muons from various directions of the celestial hemisphere. This allows us to analyze spatial-angular variations of muon flux during such events. Heliospheric disturbances that caused the changes of interplanetary magnetic field parameters measured by various space vehicles are considered. A special attention is paid to the analysis of the response of the muon hodoscope URAGAN for recent most powerful solar flares that occurred in March 2012. In accordance with the results of the study, methods of separating main heliospheric disturbances are proposed. The prognostic potential of the developed approaches to the study of heliospheric disturbances by means of the penetrating component of cosmic rays is evaluated.

We have developed particle detectors based on fused silica (quartz) Cherenkov radiators read out with micro-channel plate photomultipliers (MCP-PMTs) or silicon photomultipliers (SiPMs) for high precision timing (Sigma(t) about 10-15 ps). One application is to measure the times of small angle protons from exclusive reactions, e.g. p + p - p + H + p, at the Large Hadron Collider, LHC. They may also be used to measure directional particle fluxes close to external or stored beams. The detectors have small areas (square cm), but need to be active very close (a few mm) to the intense LHC beam, and so must be radiation hard and nearly edgeless. We present results of tests of detectors with quartz bars inclined at the Cherenkov angle, and with bars in the form of an "L" (with a 90 degree corner). We also describe a possible design for a fast timing hodoscope with elements of a few square mm., 24 pages, 14 figures

Thick gas electron multipliers (THGEMs) are new types of gas detectors with merits such as a high counting rate, anti-radiation, high gain, robustness and relatively low cost. We establish an up-down THGEM detector hodoscope system for detecting and displaying muon tracks. Muon tracks can be well observed with the detectors and the present study lays an important technological foundation for the domestic and mass production of THGEMs.

The WASA-at-COSY experiment at the Forschungszentrum Jlich provides a nearly 4π detector including a forward spectrometer especially for studies on η and η' meson decays in proton-proton collisions. Simulations have shown that an additional detector of internally reflected Cherenkov light in front of the Forward Range Hodoscope improves the particle identification and energy resolution significantly. As a first prototype test has shown the feasibility, a large scale prototype is under construction. The concept and status of the enhanced prototype, optical performance studies and main characteristics of the used photomultiplier tubes and imaging properties of the PMMA optics are described.

In an experiment at the external COSY beam associated strangeness production will be investigated [1] by measuring total and differential cross sections as well as the polarization of the produced hyperons by means of an almost 4π time-of-flight spectrometer. In a first step we will concentrate on the reaction pp → KΛp. The apparatus will consist of an inner arrangement as start detector and highly granulated scintillator hodoscopes as stop detector. Both parts give information on multiplicity and allow to identify the interesting reaction by means of the delayed charged decay of the Λ. Moreover the tracks of all prompt and delayed reaction products can be reconstructed with high precision. The detector allows the momentum measurement by time-of-flight. To get all this information the inner detector is composed of tiny granulated plastic scintillator detectors, silicon microstrip devices and a scintillating fibre hodoscope. The outer detector barrel with a diameter of about 3m and a length of about 7.5m will consist of three layers of plastic scintillator slabs, two of them bended in helix form. The status of the experiment will be presented. Moreover the results of test measurements for the different detector components will be discussed together with Monte Carlo calculations.

The neutral decay of the η'(958)-meson η' → ωγ → π0γγ → 4γ has been studied. The experiment has been performed in the IHEP 70 GeV accelerator with the multiphoton hodoscope spectrometer GAMS-2000. The measured branching ratio of the η' → ωγ decay (BR = 0.0330 ± 0.0036) is found to be in agreement with theoretical predictions.

Differential cross sections for the process pi +d to pp at seven energies in the region Tpi =280-450 MeV and in the angular range theta * approximately=4-90 degrees have been measured on the LNPI synchrocyclotron. The results include 94 new data points. The measurements have been carried out using a ten-channel hodoscope set-up. Statistical errors are between 2.5% and 7.8% depending on the scattering angle and Tpi . The data obtained indicate that there is an essential contribution from the partial wave with orbital angular momentum l=3 over the whole energy range considered. The authors also observe a noticeable contribution from the l=4 partial wave to the differential cross sections of the pi +d to pp reaction from Tpi >or=357 MeV. The total cross sections for the process pi +d to pp are also presented.

A multiparticle detector based on two large (6 m long) streamer chambers triggered by surrounding scintillation hodoscopes and viewed by cameras via image intensifiers is being assembled at CERN and tested at the ISR. Its purpose is to perform a first rapid visual survey of the new energy region afforded by the SPS p collider. Charged tracks can be observed down to 3/4°, and hence over most of the pseudorapidity range (|η| 5.0) covered by high multiplicity events. Lead glass plates are being placed within each chamber to convert gammas produced within the same η range. The apparatus is hence particularly appropriate for the detection with high efficiency of the so-called Centauro events, thought to be characterized by very large multiplicities (nch ~ 100) and by very few accompanying neutral particles.

γ, the exponent of the density spectrum of extensive air showers, is found to increase from 1.445 ± 0.014 at sea level to 1.549 ± 0.018 at 26 000 ft. The values quoted are mean values for the density range 50-500 particles per square metre. The increase is considerably less than that predicted by cascade theory on the primary electron hypothesis. It is suggested that the discrepancy may be explained by the formation of secondary cascade showers in a nucleon cascade process. Extensive air showers recorded by a fixed experimental arrangement show a maximum frequency at about 26 000 ft. (8000 m). At that altitude the shower rate is found to be 42 times the rate at sea level. The barometer coefficient of extensive air showers at sea level is found to be - (9.0 ± 1.1)% per cm Hg. Details are given of the quenching and hodoscope circuits used with the counters.

Short reaction time Geiger counters have been used at sea level to study the time coherence of associated cosmic ray particles under 18cm of Pb, and also in air. A 50-channel hodoscope has been used to identify the events giving coincidences between two 138 cm2 trays of these counters separated by 15 cm in a horizontal plane. No evidence was found for delays between associated particles of the order of 2 × 10-8 sec, as reported by Robinson using spark counters, although the counter resolving time of 1.4 × 10-8 sec should have allowed detection of the effect. Multiple hits by particles on the Geiger counter trays were found to give modified counter reaction time distributions, and it is suggested that a similar effect could occur in spark counters. A theory which accounts for the behaviour of both spark and Geiger counters under multiple hit conditions has been developed.

The axes or cores of extensive air showers have been selected by observing in a cloud chamber cascade showers produced by a single high-energy (>5 × 109 eV) electron or photon, and an upper limit of 5 m for the spread of such particles has been found. By placing trays of hodoscoped counters at various distances from this core selector it has been possible to determine the relation between density of ionizing particles and distance from the axis for showers of approximately 104-105 particles. The experimental arrangement and method of analysis used have certain advantages over those employed by other workers. It is concluded that although the results of the present experiment and those of other workers are consistent with the Moliere structure function, not too much weight should be placed on this agreement.

A portable Geiger-Muller counter apparatus is described. It includes an eight-channel hodoscope and is designed for use at great depths. Simple transistor circuit techniques are used in conjunction with magnetic tape recording. A discussion is given of the operation of counters from a stabilized voltage supply for greatest possible battery life. The complete equipment consumes about 50 mW and will operate unattended from one set of batteries for longer than a month. The apparatus has been operated successfully in a coal mine at a depth of 1500 ft below the surface.

This paper describes the construction, testing and performance of an apparatus which consists of six liquid scintillation counters, each of area 1.1 m2, interleaved with sheets of lead of thickness 2 5 radiation lengths. The pulse height from each of the counters is converted into digital form and recorded, together with hodoscope information from index counters above and below the stack, on standard five-hole tape. At a depth of 60 m.w.e. below sea level the total event rate is about 2 sec-1. The classification system used for distinguishing the various types of events is also described.

A multi-channel Geiger counter hodoscope is described which records automatically on punch cards, uses a simple but effective quenching circuit and contains a testing circuit. An automatic hourly test is applied to all channels, providing a random sample of their behaviour and enabling speedy detection of faults either in the counters themselves or the associated recording circuits.