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The definition of the magnetic center in the Mu2e solenoid system is not trivial given the S-shaped nature of the transport solenoid. Moreover, due to the fringe field of the larger bore adjacent magnets—production solenoid and the detector solenoid—the magnetic center does not coincide with the geometric center of the system. The reference magnetic center can be obtained by tracking a low-momentum charged particle through the whole system. This paper will discuss this method and will evaluate the deviations from the nominal magnetic center given the tolerances in the manufacturing and the alignment of the coils. Methods for the correction of the magnetic center will also be presented. [ABSTRACT FROM PUBLISHER]

The ATLAS Tile hadronic calorimeter (TileCal) provides highly-segmented energy measurements for incident particles. Information from TileCal’s last radial layer can assist in muon tagging and has been considered for inclusion in an upgraded Level-1 trigger. It can assist in the rejection of fake muon triggers arising from background radiation without degrading the efficiency of the trigger. This paper addresses the additional muon discrimination obtained by using a new receiver for the TileCal signals which interfaces with the current ATLAS Level-1 muon trigger. The design and performance of the receiver are also described. [ABSTRACT FROM PUBLISHER]

The paper describes the prototype of a synchronous (Master/Slave) data acquisition system for underground muon counters triggered by surface detectors. A water Cherenkov surface detector (Master) when hit by extensive air showers generates and transmits the trigger to the underground system (Slave) to register the muon fraction of the showers which survived the propagation through 3 m layer of soil. The surface and underground segments are built on the Altera field-programmable gate array (FPGA) CycloneIII/CycloneIV platforms, respectively. Both FPGAs are equipped with NIOS processors, which makes previously used external microcontrollers unnecessary. They also generate necessary interfaces: SDRAM controller, UART, SPI, DMA; interfaces which were previously implemented by means of logic elements. Moving several time-consuming tasks from the logic block (coded in the Altera Hardware Description Language) to the NIOS (coded in “C”) dramatically simplifies the system and increases its flexibility. The time margin for all processes managed by the soft-core NIOS for the 100 Hz T1 trigger rate remains sufficient. NIOS processors communicate with each other via UART protocol and by the RS485 standard. The underground CycloneIV FPGA is programmed remotely via additional MAXII CPLD with nonvolatile programmable memory. Tests have shown that a full string of data processing goes smoothly. The above-mentioned string involves the following processes: the transfer of the trigger with a time stamp from the surface detector into the underground segment via a dedicated line with a galvanic barrier, freezing data from 64 channels at 320 MHz sampling in internal DPRAMs, writing/reading data into/from external SDRAM, extracting physical data identified by GPS time stamps sent from Central Data Acquisition System (CDAS) and the data transfer from the underground NIOS via the surface NIOS to CDAS. [ABSTRACT FROM PUBLISHER]

The Large Hadron Collider beauty (LHCb) experiment [1] at the LHC has been designed and built to search for signs of new physics phenomena beyond the Standard Model of particle physics in the decays of heavy particles made of beauty (b) and charm (c) quarks, created in proton-proton (pp) collisions at the LHC in Geneva, Switzerland. In particular, the LHCb is expected to study the reasons for which matter and anti-matter had different fates just after the initial Big Bang, and now we observe only matter. In fact, all experimental observations point to the conclusion that the current Universe is matter dominated, and there is no evidence of relic anti-matter, which was abundant in the early instants. The violation of CP (combination of Charge and Parity symmetries) is the experimental observation made for the first time in 1964 that particles and anti-particles may behave differently in their decays. [ABSTRACT FROM PUBLISHER]

In this paper, high-altitude measurements of both radiation environment and effects are described. Measurements are made using a neutron spectrometer and CCD camera. MUSCA SEP3 software is used to correlate both measurement approaches. Analyses of the charge levels in pixels induced by radiation events are proposed. Then, cross-comparison analyses based on a CCD camera and HERMEIS neutron spectrometer are performed to investigate radiation dynamic properties, including neutron/proton and muon contributions. [ABSTRACT FROM PUBLISHER]

We present experimental evidence of single-event upsets in 28 and 45 nm CMOS SRAMs produced by single energetic electrons. Upsets are observed within 10% of nominal supply voltage for devices built in the 28 nm technology node. Simulation results provide supporting evidence that upsets are produced by energetic electrons generated by incident X-rays. The observed errors are shown not to be the result of “weak bits” or photocurrents resulting from the collective energy deposition from X-rays. Experimental results are consistent with the bias sensitivity of critical charge for direct ionization effects caused by low-energy protons and muons in these technologies. Monte Carlo simulations show that the contributions of electron-induced SEU to error rates in the GEO environment depend exponentially on critical charge. [ABSTRACT FROM PUBLISHER]

Single Event Upset (SEU) measurements were performed on the ESA SEU Monitor using mono-energetic GeV-energy hadron beams available in the North Experimental Area at CERN. A 400 GeV proton beam in the H4IRRAD test area and a 120 GeV mixed pion and proton beam at the CERN-EU high Energy Reference Field facility (CERF) were used for this purpose. The resulting cross section values are presented and discussed as well as compared to the several hundred MeV case (typical for standard test facilities) from a physical interaction perspective with the intention of providing a more general understanding of the behavior. Moreover, the implications of the cross section dependence with energy above the several hundred MeV range are analyzed for different environments. In addition, analogous measurements are proposed for Single Event Latchup (SEL), motivated by discussed simulation results. Finally, a brief introduction of the future CHARM (CERN High-energy AcceleratoR Mixed facility) test installation is included. [ABSTRACT FROM PUBLISHER]

The trigger based on the Discrete Cosine Transform (DCT) allows recognition of ADC traces of a specific shape i.e., with a very short rise time and fast exponential attenuation related to a narrow, flat muon component of very inclined extensive air showers generated by hadrons and starting their development early in the atmosphere (“old” showers). Showers, crossing a surface detector composed of water Cherenkov tanks, such as those in the Pierre Auger Observatory generate Cherenkov light, which may hit photomultipliers (PMTs) directly or after several reflections. The geometry of the water Cherenkov tank imposes a type of the filter preferring the detection of very inclined showers (with very large zenith angle), where mainly two PMTs can be hit by direct light. The 3rd PMT is then hit by reflected light, but with some delay. For the fast sampling (80 MHz), this delay causes the signal to appear in the next time bin. Two-fold coincidences of DCT coefficients allow triggering signals that are ignored at that time due to either too high an amplitude threshold for three-fold coincidences in a single time bin (the standard Auger threshold trigger) or due to the de-synchronization of the signals in time caused by the tank geometry (delay on one or more time bins due to a longer light path corresponding to the reflection on the tank walls). Three DCT engines implemented into EP3C40F324I7 FPGA use all DSP blocks and generate the spectral trigger, when 8 DCT coefficients simultaneously are inside the acceptance lane in at least 2 channels. An additional veto signal (analyzing the amplitude) controls the trigger rate to avoid a saturation of a transmission channel. In a test performed in the Pierre Auger laboratory in Malargue (Argentina), the spectral trigger has been tuned for shapes corresponding to “old” showers. Both laboratory and long-term field measurements on a test tank confirmed a high efficiency of the recognition of expected patterns of ADC traces. The patterns of the spectral trigger for “young” showers are being optimized in simulations. We expect to detect “young” showers close to their cores. [ABSTRACT FROM AUTHOR]

The upcoming Belle II experiment is designed to work at a luminosity of 8\times 10^35 cm^-2s^-1, 40 times higher than its predecessor. The pixel detector of Belle II with its \sim8 million channels will deliver ten times more data than all other sub-detectors together. A data rate of 22 Gbytes/s is expected for a trigger rate of 30 kHz and an estimated pixel detector occupancy of 3%, which is by far exceeding the specifications of the Belle II event builder system. Therefore a realtime data reduction of a factor > 30 is needed. [ABSTRACT FROM AUTHOR]

Single Event Upset (SEU) measurements were performed using the European Space Agency's (ESA) Standard SEU Monitor in the H4 Irradiation mixed-field test area at CERN. The results, tightly correlated with the radiation environment, are compared with those obtained with the CERN Radiation Monitors (RadMons) as well as with the Monte Carlo simulation of the experimental setup using the FLUKA Monte Carlo transport code. In addition, the SEU cross section of the device for particles and energies not available in standard testing (such as charged pions or GeV-energy hadrons) are simulated and discussed, showing an increase of over a factor 2 for nucleons in the 200 MeV–3 GeV range. A monoenergetic SEU cross section measurement at 120 GeV is included in the analysis. [ABSTRACT FROM AUTHOR]

The NA62 RICH detector is used for the separation of pions and muons in the momentum range 15–35 GeV/c and is expected to provide a muon suppression factor better than 10^-2. A prototype of the final detector equipped with about 400 PMs (RICH-400 prototype) was built and tested in a dedicated run in 2009. The \pi-\mu separation was tested, as well as the effect of the contamination of the neon radiator with different amounts of oxygen and CO2. The \mu misidentification probability is about 0.7% and the time resolution better than 100 ps in the whole momentum range. We did not observe any absorption of the light due to the contamination of the radiator, however an effect on the ring radius is clearly observed due to the change of the refractive index of the medium. The conclusion of the studies is that the amount of CO2 in the final detector should be known at the 10^-3 level of precision or the quality of the pion identification could be seriously compromised. [ABSTRACT FROM PUBLISHER]

The Fermilab Mu2e experiment seeks to measure the rare process of direct muon to electron conversion in the field of a nucleus. Key to the design of the experiment is a system of three superconducting solenoids; a muon production solenoid (PS) which is a 1.8 m aperture axially graded solenoid with a peak field of 5 T used to focus secondary pions and muons from a production target located in the solenoid aperture; an “S shaped” transport solenoid (TS) which selects and transports the subsequent muons towards a stopping target; a detector solenoid (DS) which is an axially graded solenoid at the upstream end to focus transported muons to a stopping target, and a spectrometer solenoid at the downstream end to accurately measure the momentum of the outgoing conversion electrons. The magnetic field requirements, the significant magnetic coupling between the solenoids, the curved muon transport geometry and the large beam induced energy deposition into the superconducting coils pose significant challenges to the magnetic, mechanical, and thermal design of this system. In this paper a conceptual design for the magnetic system which meets the Mu2e experiment requirements is presented. [ABSTRACT FROM PUBLISHER]

A program to develop model magnets for a helical cooling channel is under way at Fermilab. In the first steps of a planned sequence of magnets, two four-coil helical solenoid models with 300 mm aperture have been fabricated and tested. These two models, HSM01 and HSM02, used insulated NbTi Rutherford cable wound onto stainless steel rings with spliceless transitions between coils. Strip heaters were included for quench protection of each coil, and the coils were epoxy-impregnated after winding inside the support structures. Based on the results of the first model the second model was made using a cable with optimized cross-section, improved winding and epoxy-impregnation procedures, enhanced ground insulation, and included heat exchange tubing for a test of conduction cooling. We report on the results and lessons learned from fabrication and tests of these two models. [ABSTRACT FROM PUBLISHER]

In this work we present the design, the construction and the measurements of the magnet for a so-called spin-rotator (Wien filter), a beam line device used to rotate the spin direction (and the associated magnetic moment) of muons in a beam used for condensed matter research at the Swiss Muon Source at the Paul Scherrer Institute. The design parameters—originating both from the properties of the preferred particle beam as well as the technological constraints for the high-voltage components generating the necessary electric field—were optimized for device compactness, cost and high beam transmission. [ABSTRACT FROM PUBLISHER]

A muon tracking system consisting of four 9 cm \times\,10 cm sized bulk Micromegas detectors with 128 \mum amplification-gap and two 10 cm \times\,10 cm triple GEM detectors is foreseen for high-precision tracking of 160 GeV muons at the H8 beamline at CERN with a readout rate above 10 kHz and an overall resolution below 20 \mum. Signal studies of both detector types have been performed by recording cosmic muon and 5.9 keV X-ray signals. The analysis of the complete signal-cycles allows for the determination of rise times, pulse heights, timing fluctuations and discrimination of background, resulting in a FWHM energy resolution of about 20% and detection efficiencies of 98% and more. Models for signal formation in both detector types will be presented. A single detector spatial resolution of 75 \mum was measured for cosmic muons using a fast Gassiplex based strip readout with readout strips of 150 \mum width and a pitch of 250 \mum. Multiple scattering of low energy cosmic muons deteriorates the observable spatial detector resolution by more than 20 \mum. Additionally, we report on the sensitivity to gamma- and neutron background and on the behavior of spatial resolution as a function of background rates. [ABSTRACT FROM AUTHOR]

With the tenfold luminosity increase envisaged at the HL-LHC, the background (i.e., photons, neutrons, \ldots) and the event pileup probability are expected to highly increase in proportion in the different experiments, especially in the forward regions, for instance the muons chambers of the ATLAS detector. Detectors based on the Micromegas principle should be good alternatives for the detector upgrade in the HL-LHC framework because of its good spatial (< 100\mu\m) and time (few ns) resolutions, high-rate capability, radiation hardness, good robustness, and the possibility to build large areas. The aim of this study is to demonstrate that it is possible to reduce the discharge probability and protect the electronics by using a resistive anode plane in a high-flux hadrons environment. Several prototypes of 10 \times 10~\cm^2, with different pitches (0.5–2 mm) and different resistive layers have been tested at CERN (\pi^+@SPS). Several tests have been performed with a telescope at different voltages to assess the performance of the detectors in terms of position resolution and efficiency. The spark behavior in these conditions has also been evaluated. Resistive coating has been shown to be a successful method to reduce the effect of sparks on the efficiency of micromegas. A good spatial resolution (\sim 80\ \mu\m) can be reached with a resistive strip coating detector of 1-mm pitch, and a high efficiency ( > 98\%) can be achieved with resistive-anode micromegas detector. An X-rays irradiation has also been performed, showing no ageing effect after more than 21 days exposure and an integrated charge of almost 1C. [ABSTRACT FROM AUTHOR]

This paper describes the Plateau de Bure Neutron Monitor (PdBNM), an instrument providing continuous ground-level measurements of atmospheric secondary neutron flux resulting from the interaction of primary cosmic rays with the Earth's atmosphere. The detector is installed on the Plateau de Bure (Devoluy mountains, south of France, latitude North 44^\circ 38' 02'', longitude East 5^\circ 54' 26'', altitude 2555 m) as a part of the ASTEP Platform (Altitude Single-event effects Test European Platform), a permanent installation dedicated to the study of the impact of terrestrial natural radiation on microelectronics circuit reliability. The present paper reports the neutron monitor design, its operation since August 2008 and its complete numerical simulation using the Monte Carlo codes GEANT4 and MCNPX. We particularly detail the computation of the neutron monitor detection response function for neutrons, muons, protons and pions, the comparison between GEANT4 and MCNPX numerical results and the evaluation of the PdBNM counting rate as function of both the nature and flux of the incident atmospheric particles. [ABSTRACT FROM AUTHOR]

The aim of the AMIGA project (Auger Muons and Infill for the Ground Array) is an investigation of Extensive Air Showers at energies lower than those accesible with the standard Auger array, where the transition from galactic to extragalactic sources is expected. The paper describes the working principle of the Master/Slave (standard Auger surface detector/the underground muon counters) synchronous data acquisition and general triggering applied in two prototypes: with 12.5 ns resolution built from 4 segments (2 FPGAs and 2 standard micro-controllers) and 3.125 ns resolution built from two segments only (2 FPGAs with implemented NIOS® processors). [ABSTRACT FROM PUBLISHER]

The super-KEKB B factory, currently under construction at the KEK High Energy Accelerator Research Organization in Japan, has a goal of producing 50 ab^-1 of integrated luminosity, thus allowing the Belle II experiment to study rare decays of B mesons, D mesons, and \tau leptons. Such large statistics on these decays provide an experimental probe of physics beyond the Standard Model. An online trigger system is indispensable to Belle II to reduce the number of beam background events associated with high electron and positron beam currents, as well as to enhance physics-oriented events. For this purpose, we have designed the Belle II online trigger system with two kinds of primary Level 1 trigger components: a track trigger and an energy trigger. The track trigger is composed of 2-dimensional and 3-dimensional tracking algorithms, and the energy trigger implements algorithms based on total energy, isolated clusters, and identification of Bhabha events. In addition, precise event trigger timing and muon tagging information are provided by the time-of-propagation detector and iron flux return muon detector, respectively. [ABSTRACT FROM PUBLISHER]

A quench protection system for superconducting curved segmented solenoids has been experimentally studied. The curved solenoids consist of short straight solenoids aligned along a curved beamline axis. The quench propagation between the short solenoids may not naturally occur because of the separation between the solenoids, and an artificial quench need to be induced by a protection heater for each short solenoid to boost the quench propagation. A protection heater driven by the coil self current was tested with a model coil. [ABSTRACT FROM AUTHOR]

The construction of the 1st phase Japan Proton Accelerator Research Complex (J-PARC) was completed. Three major experimental facilities, which have been utilized by users, are instrumented with the superconducting magnet systems; a muon transport solenoid in Materials and Life Science Experimental Facility, a superconducting spectrometer in Hadron Experimental Facility, and a 150 m superconducting beam line in Neutrino Experimental Facility. There are also several superconducting magnet systems proposed as part of future experiments at J-PARC. The paper briefly summarizes the current status of the superconducting magnet systems currently in operation, and introduces the superconducting magnet systems associated with the new proposals. [ABSTRACT FROM AUTHOR]

A 3-GeV (333 \muA, 1.0 MW) proton beam from the J-PARC Rapid Cycle Synchrotron passes through a graphite target producing muons in the Materials and Life Science Facility. Muons of various momenta of up to 50 MeV/c and of both electric charges are captured and transported to an experimental area by using an axial magnetic field in the bore of solenoid magnets. This beam line, named Super Omega, is composed of a normal conducting MIC (Mineral Insulation Cable) magnet for capture, a curved superconducting solenoid system for transportation, and an axial focusing magnet system. Once in the experimental area, the muon beam is focused onto an experimental target for various purposes. The superconducting solenoid system is composed of one 6-m long straight section and two 45-degree segmented curved sections at both ends of the straight section. A magnetic field of about 2 T is applied in the transportation channel of 300 mm in diameter. The conceptual design of this solenoid system is reported. [ABSTRACT FROM AUTHOR]

The new muon beamline, MuSIC, is being constructed at the Research Center for Nuclear Physics (RCNP) at Osaka University in Japan. The project utilizes superconducting solenoid magnets to collect pions and to transport muons with the ultimate efficiency by putting pion-production target inside the solenoid magnet. This is the first of such a novel method to produce intense muon beams. All the superconducting coils are cooled with conduction cooling using Gifford-McMahon cryocoolers. A large superconducting coil with the diameter of 90 cm encloses the pion-production target and thick shielding to protect the coil against severe radiation from the target, so that energy deposit by particles on the coil should be less than 1 W. Pions are captured in a 3.5 T magnetic field and are injected into the subsequent toroidal magnets with the magnetic field of 2 T. Superconducting dipole coils are equipped on each solenoid coil of the transport solenoid to correct the particle trajectory in the toroidal field. The design and construction status of the solenoid channel are described in this paper. [ABSTRACT FROM AUTHOR]

Basic R&Ds of a superconducting solenoid for a new g-2 experiment at J-PARC are on going. High uniformity of magnetic field below 0.1 ppm is required for the g-2 experiment within a storage region of 33.3 \pm5 cm in radius and \pm10 cm in height. Two R&Ds have been started to develop the magnet with such high uniformity; a development of a precise field monitoring system and a study of seismic ground vibration. The prototype monitoring system using continuous wave type NMR probe for horizontal MRI solenoid has been built and tested. Cross-check between NMR and Hall probe has been also carried out. The seismic ground vibration has been measured at Materials and Life science Facility, MLF, in J-PARC. Based on the measured results, the spectrum analysis of the iron yoke has been performed using ANSYS. [ABSTRACT FROM AUTHOR]

An intense muon beam is mandatory for next-generation experiments to search for lepton flavor violating processes in the muon sector. The COMET experiment, J-PARC E21, aims to search for muon to electron conversion with an unprecedented sensitivity. All the components of the experiment, such as the pion production target, the muon stopping target and the tracker are embedded in superconducting solenoids, resulting in a total length longer than 30 m. The pions are captured in a 5 T solenoid magnet with a diameter of 1.3 m, and decay to muons in the subsequent 3 T toroidal magnets over a length of 10 m. The pion capture solenoid is designed to be as small as possible, however, thick shielding is necessary within the solenoid to avoid severe radiation from the target. Aluminum-stabilized NbTi superconducting wire is employed to reduce the cold mass and energy deposited in it. The damage of the conductor of the coils should be estimated carefully, since the expected neutron fluence reaches 10^22\ neutrons/m^2. This paper describes the design of the solenoid magnets and R&D programs. [ABSTRACT FROM AUTHOR]

This paper has designed a cross-layer framework for voice over Internet protocol (VoIP) services in IEEE 802.16 systems. It uses the application session information of the session description protocol to generate the quality of service parameters in IEEE 802.16 systems. This feature allows the system to efficiently allocate the radio resource because it can exactly estimate the properties of VoIP services such as packet-size and packet-generation-interval. In other words, the cross-layer framework is expected to achieve a novel resource request scheme for a VoIP service that dynamically assigns the radio resource. This paper has analyzed the maximum number of supportable VoIP users for the resource request schemes in terms of the packet-generation-interval in the silent-period, the duration of the silent-period, and the major VoIP speech codec. The numerical results show that the proposed scheme can efficiently support the VoIP services for the various communication environments. Particularly, it can improve the maximum number of supportable VoIP users by 14\sim 93\% compared to an extended real-time polling service. [ABSTRACT FROM PUBLISHER]

The LHCb muon readout apparatus is made of 1368 Multi-Wire Proportional Chambers (MWPC) and 24 Gas Electron Multiplier (GEM) chambers connected to 7632 16-channel front-end boards, resulting in 122.112 channels to be read out. After a pp collision, all the resulting signals must be read within 25 ns, before the next collision. The large-scale of the system and the time constrains naturally led to the development of a custom and complex control system made of about 600 microcontrollers (\mu C) and 150 flash-based FPGAs which are directly connected to the front-end electronics and handled by six computers. Besides configuring and monitoring the on-chamber readout electronics, a set of calibration and debugging oriented procedures have been developed to measure the noise, to time align and to assess the connection chains of every single channel of the detector. This document presents and describes the electronics developed to this purpose. [ABSTRACT FROM AUTHOR]

Experimental data are presented that show low-energy muons are able to cause single event upsets in 65 nm, 45 nm, and 40 nm CMOS SRAMs. Energy deposition measurements using a surface barrier detector are presented to characterize the kinetic energy spectra produced by the M20B surface muon beam at TRIUMF. A Geant4 application is used to simulate the beam and estimate the energy spectra incident on the memories. Results indicate that the sensitivity to this mechanism will increase for scaled technologies. [ABSTRACT FROM AUTHOR]

We present a custom integrated circuit, named SYNC, which plays a fundamental role in the time alignment of the LHCb Muon Detector and consequently in the trigger performance. The SYNC is realized in IBM 0.25~\mu m technology, using radiation-hardening layout techniques. SYNC receives data from the muon detector front-end electronics synchronizing them with the 40.08 MHz LHC clock. The data are tagged with the correct Bunch-Crossing identifier, output to the trigger system and stored in internal memories. The chip integrates 8 time to digital converters with a resolution up to 1 ns to measure the time phase of the input signals with respect to the system clock period. A histogram block can build real time spectra from the TDCs output. A I^2C interface is implemented to configure and control the device, while a JTAG interface is integrated for boundary-scan purpose. We describe the circuit architecture, its internal blocks and its main modes of operation. Measurements performed on final prototypes are also reported. [ABSTRACT FROM PUBLISHER]

The Daya Bay RPC (Resistive Plate Chamber) readout system is responsible for collecting event data created by muons entering the detector systems from above. The readout system should be capable of converting analog signals from the RPC detectors into digital signals, which are buffered and uploaded for readout by the online DAQ (Data Acquisition) system. The RPC readout system will report trigger information to a master trigger system. The numerous and relatively minute pulses from the RPC detectors require accurate signal discriminating and reliable data transmission. This article provides a brief overview of the Daya Bay RPC detector and then outlines the design and performance of the prototype RPC readout system. [ABSTRACT FROM AUTHOR]

We have designed a threshold Cherenkov detector at the Rutherford-Appleton Laboratory to identify muons with momenta between 230 and 350 MeV/c. We investigated the properties of three aerogels for the design. The nominal indices of refraction were n, = 1.03,1.07, 1.12, respectively. Two of the samples are of high density aerogel not commonly used for Cherenkov light detection. We present results of an examination of some optical properties of the aerogel samples and present basic test beam results. [ABSTRACT FROM AUTHOR]

The proton-proton beam crossing at the LHC accelerator at CERN will have a rate of 40 MHz at the project luminosity. The ATLAS Trigger System has been designed in three levels in order to select only interesting physics events reducing from that rate of 40 MHz to the foreseen storage rate of about 200 Hz. The First Level reduces the output rate to about 100 kHz. The ATLAS Muon Spectrometer has been designed to perform stand-alone triggering and measurement of Muon transverse momentum up to 1 TeV/c with good resolution (from 3% at 10 GeV/c up to 10% at 1 TeV/c). In the Barrel region of the Muon Spectrometer the Level-1 trigger is given by means of three layers of resistive plate chamber detectors (RPC): a gaseous detector working in avalanche mode composed by two plates of high-resistivity bakelite and two orthogonal planes of read-out strips. The logic of the Level-1 barrel Muon trigger is based on the search of patterns of RPC hits in the three layers consistent with a high transverse momentum Muon track originated from the interaction vertex. The associated trigger electronics is based on dedicated processors, the Coincidence Matrix boards, performing space coincidences and time gates and providing the RPC readout as well. A detailed simulation of the ATLAS Experiment and of both the hardware components and the logic of the Level-1 Muon Trigger in the barrel of the Muon Spectrometer has been performed. This simulation has been used not only to evaluate the performances of the system but also to define the hardware set-up such as the cabling of both the trigger detectors and the trigger electronics modules. A description of both the Level-1 Muon Trigger system in the barrel and the RPC detectors, with their cosmic rays quality tests, will be presented together with the trigger performances and rates calculations evaluated for Muons over a wide range of PT and preliminary studies on the impact of accidental triggers due to low energy background particles in the experimental area. [ABSTRACT FROM AUTHOR]

The Large Hadron Collider at CERN offers unprecedented challenges to the design and construction of detectors and trigger/data acquisition systems. For ATLAS, a three level trigger system has been developed to extract interesting physics signatures with a 106 rate reduction. To accomplish this, components of physics analysis traditionally deferred to off-line physics analysis must be embedded within the on-line trigger system. For the Muon trigger, the specific off-line algorithms MOORE (Muon Object Oriented REconstruction) and MuId (Muon Identification) have been adopted so far for the on-line use, imposing an operation in a Bayesian-like environment where only specific hypotheses must be validated. After a short review of the ATLAS trigger, the paper shows the general strategy of the Muon Identification and Selection accessing the full event data, or being seeded from results derived at a previous stage of the trigger chain. [ABSTRACT FROM AUTHOR]

A set of models for Monte Carlo simulation of production and interaction of high energy muons is developed in the framework of the Geant4 toolkit. It describes the following physics processes: ionization of high energy muons with radiative corrections, bremsstrahlung, electron-positron pair production, muon induced nuclear reactions, gamma annihilation into muon pair, positron annihilation into muon pair, and into pion pair. These processes are essential for the LHC experiments, for the understanding of the background in underground detectors, for the simulation of effects related with high-energy muons in cosmic ray experiments and for the estimation of backgrounds in future colliders. The applicability area of the models extends to 1 PeV. The major use-cases are discussed. [ABSTRACT FROM AUTHOR]

For the purpose of new physics search in rare B meson decays, an upgrade of the KEKB accelerator is being planned where the luminosity becomes more than ten times higher. The trigger rate with the increased luminosity is expected to reach up to 30 kHz with the event size of ∼300 kB. A new event builder is designed to cope with the condition by modularizing the system currently used in the Belle experiment and by operating multiple units in parallel. A test bench is built to study the new design and results of performance tests are reported. [ABSTRACT FROM AUTHOR]

In order to explore new physics in B-meson decays we plan to upgrade the KEK B-factory to a luminosity of 5 × 1035 cm-2s-1. In parallel we are developing a new pipelined data acquisition system for the Belle detector to cope with higher trigger rates of up to 30 kHz and severe background conditions. In order to reduce development and maintenance costs, we have adopted a modular design for these new readout electronics. The chosen architecture consists of a common readout platform, upon which are mounted subdetector specific parts, customized to meet the readout requirements of each sub detector component. As an example of this new architecture, we present in this paper the design of drift chamber electronics. The drift chamber readout utilizes the AMT-3 time-to-digital converter chip, originally developed for the ATLAS experiment, which satisfies the performance requirement for current and future Belle drift chamber readout. A data transfer performance test with emulation modules, mounted on the common platform, shows that the new readout electronics works well at a more than 30 kHz input trigger rate. [ABSTRACT FROM AUTHOR]

To—the fast timing and trigger detector for the ALICE experiment at CERN LHC—is described. Performance of the TO prototype measured with a mixture of 6 GeV/c negative pions and kaons is given. The best time resolution (28 ps r.m.s.) was reached with a radiator diameter matching that of the photocathode. The results for all the tested radiator sizes are considerably better than 50 ps—the minimum requirement for the ALICE experiment. [ABSTRACT FROM AUTHOR]

LHCb is one of the experiments at the Large Hadron Collider at CERN. It aims to make precision measurements of CP violation in the B-meson decays. The detector simulation of LHCb was developed using the GEANT4 software toolkit interfaced to the LHCb software framework named GAUDI. This is now being used for a large production run of 210 million events. An important feature of the LHCb experiment is the use of Ring Imaging Cherenkov Counters (RICH) for particle identification. The Cherenkov photons created in this detector are focused onto an array of photodetectors made of Hybrid Photon Detectors. A brief overview of the GEANT4 based LHCb simulation program named GAUSS will be given with the main emphasis on RICH simulation and its verification. [ABSTRACT FROM AUTHOR]

An international collaboration plans to measure the lifetime of the muon to a precision of 1 part per million [1]. The "MuLan" experiment wilt take place at the Paul Scherrer Institut (PSI) in Northern Switzerland. The MuLan experiment requires a fast beam line kicker, which can turn the beam on and off, to invoke an artificial time structure on the continuous beam which has a 50.6-MHz time microstructure. The kicker needs to run with a standard "on-off time cycle" or in a "Muon on Request" mode. The MuLan kicker consists of two pairs of deflector plates mechanically in series, driven by four modulators. Each modulator consists of two stacks of MOSFETs operating in push-pull mode. The specifications for the kicker demand that the rise and fall times of the deflector plate voltage do not exceed 45 ns. There is a requirement for an adjustable output voltage from 0 V to ± 12.5 kV per deflector plate, a minimum pulse duration of 200 ns, and adjustable repetition rate up to a maximum of 50 kHz, continuous. Short turn-on and turn-off delays are required for the "Muon on Request" mode; the measured propagation delay is 200 ns. The specifications also require that the polarity of the pulses on the plates be selectable, although not on a pulse-by-pulse basis. This paper describes the novel design of the kicker and presents both predictions and measurements. [ABSTRACT FROM AUTHOR]

A time-of-flight (TOF) detector has been added to the CDF-II experiment to provide charged kaon identification primarily for neutral B meson flavor determination. The TOF front-end electronics system has 432 channels and is designed to run at the 7.58 MHz clock rate in CDF. The electronics contributes less than 10 ps to the TOF timing resolution of 120 ps, which is dominated by photon statistics. This paper describes the design and implementation of the electronics as well as the in situ performance. [ABSTRACT FROM AUTHOR]

Deals with a study which examined the optical link concepts for both the analogue readout and digital control of the Compact Muon Solenoid Tracker. Optical link systems; Analogue link performance; Digital link performance; Conclusion.

Presents the design and commissioning of a multiplicity veto for the HERA-B detector, a fixed-target spectrometer originally designed to study the physics of B mesons in proton-nucleus interactions. Overview of the electronics board; Commissioning of the RICH multiplicity veto system; Conclusion.

Deals with a study which constructed a slice test system for the ATLAS end-cap muon level-1 trigger. Overview of thin gap chamber trigger system; Setup for slice test; Test results.

Deals with a study which observed the increase in the beam associated background rate leading to a lower detection efficiency in the endcap K[subL] mesons and muons (KLM) detector. Background observed in the encap KLM detector; Geometry of the endcap KLM detector system for simulations; Conclusion.

Describes the performance of the DIRC, a novel type of Cherenkov ring imaging device, during the first 2.5 years of operation. Requirement of the study of the violation of the charge conjugation and parity symmetry using hadronic final states of the B B-meson system; Location of the particle identification system (PID); Description of the PID system being used in the BABAR; Basis of the DIRC concept.

Presents information on a study which investigated the performance of the endcap RPC modules in the BELLE detector. Comparison of the BELLE and KLM detectors; Identification of muons; Angle correlation between a certain meson and its correlation with the missing momentum direction.