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The MEG II experiment, located at the Paul Scherrer Institut (PSI) in Switzerland, is the successor to the MEG experiment, which completed data taking in 2013. MEG II started fully operational data taking in 2021, with the goal of improving the sensitivity of the μ + → e + γ decay down to ∼ 6 × 10 - 14 almost an order of magnitude better than the current limit. In this paper, we describe the operation and performance of the experiment and give a new estimate of its sensitivity versus data acquisition time. [ABSTRACT FROM AUTHOR]

A R744 (CO 2) refrigeration system has been designed to cool down the Large Hadron Collider (LHC) silicon detectors ATLAS and CMS, located at CERN, Switzerland. The silicon detectors are subjected to high radiation levels. The system is composed of a pri- mary CO 2 trans-critical booster vapor compression loop operated with piston compressors, and an oil-free liquid pumped loop on the evaporation side, to preserve the detectors. To ensure the system's reliability, the cooling facility is designed to operate under a parallel operation mode of several modular 70 kW plant units providing evaporation temperature as low as -53 °C. This layout, is also useful in case of components failure and maintenance. A numerical model is developed using a dynamic simulation software Dymola that is based on the open source Modelica modelling language. The simulation results are proven on a first demonstration plant (System A) experimentally to explore the systems control logic and to validate the reliability of the system before it is built on the detectors side. In this paper the models development is explained and the results of the experimental validation of the numerical model are shown. [ABSTRACT FROM AUTHOR]

At the Paul Scherrer Institute (PSI) in Switzerland, cancer patients are treated with protons. The PSI Gantries work with Pencil Beam Scanning (PBS) technology. For beam profile characterization, a new 2-D planar pixel detector based on Printed Circuit Board technology was developed. The main challenge of the design was the limited amount of 256 readout channels while several thousands of detector signals had to be processed. With PBS, only a few pixels will be hit by the proton beam and give a significant signal, while most of them will not capture any signal. On the detector design, the active area was divided into pixel arrays with equal size, while one array is such big to cover the whole size of the proton beam. By a so-called channel recycling technique, the same pixel number of all pixel arrays were connected together to one readout channel. The proof of concept was verified with a small detector. In the next step, the design was changed such, getting a full-scale detector for Gantry 2. The readout electronics board itself is also a development performed at PSI. A core component of the design is the ADAS1128 chip from ANALOG Devices featuring 128 input channels. The pixel detector is fully integrated into the therapy control system (TCS) through readout electronics with a field-programmable gate array (FPGA) technology. The FPGA technology allows to readout the detector synchronized to the beam delivery. This paper summarizes the features of the pixel detector design, the readout electronics, and shows the first experimental results. [ABSTRACT FROM AUTHOR]

It is essential to accurately assess and verify the effects of air pollution on human health and the environment in order to develop effective mitigation strategies. More accurate analysis of air pollution can be achieved by utilizing a higher-density sensor network. In recent studies, the implementation of low-cost sensors has demonstrated their capability to quantify air pollution at a high spatial resolution, alleviating the problem of coarse spatial measurements associated with conventional monitoring stations. However, the reliability of such sensors is in question due to concerns about the quality and accuracy of their data. In response to these concerns, active research efforts have focused on leveraging machine learning (ML) techniques in the calibration process of low-cost sensors. These efforts demonstrate promising results for automatic calibration, which would significantly reduce the efforts and costs of traditional calibration methods and boost the low-cost sensors' performance. As a contribution to this promising research field, this study aims to investigate the calibration transferability between identical low-cost sensor units (SUs) for NO 2 and NO using ML-based global models. Global models would further reduce calibration efforts and costs by eliminating the need for individual calibrations, especially when utilizing networks of tens or hundreds of low-cost sensors. This study employed a dataset acquired from four SUs that were located across three distinct locations within Switzerland. We also propose utilizing O 3 measurements obtained from available nearby reference stations to address the cross-sensitivity effect. This strategy aims to enhance model accuracy as most electrochemical NO 2 and NO sensors are extremely cross-sensitive to O 3. The results of this study show excellent calibration transferability between SUs located at the same site (Case A), with the average model performance being R2 = 0.90 ± 0.05 and root mean square error (RMSE) = 3.4 ± 0.9 ppb for NO 2 and R2 = 0.97 ± 0.02 and RMSE = 3.1 ± 0.8 ppb for NO. There is also relatively good transferability between SUs deployed at different sites (Case B), with the average performance being R2 = 0.65 ± 0.08 and RMSE = 5.5 ± 0.4 ppb for NO 2 and R2 = 0.82 ± 0.05 and RMSE = 5.8 ± 0.8 ppb for NO. Interestingly, the results illustrate a substantial improvement in the calibration models when integrating O 3 measurements, which is more pronounced when SUs are situated in regions characterized by elevated O 3 concentrations. Although the findings of this study are based on a specific type of sensor and sensor model, the methodology is flexible and can be applied to other low-cost sensors with different target pollutants and sensing technologies. Furthermore, this study highlights the significance of leveraging publicly available data sources to promote the reliability of low-cost air quality sensors. [ABSTRACT FROM AUTHOR]

The project presented in this paper, the CMS muon detector, is fully described in Ref. 1. It was designed from 1991 to 19945 by a community of physicists and engineers from universities and institutes of several countries. The details of the design were fixed in 1997 with the submission of the CMS Muon Technical Design Report.4 This paper reflects the views, the memoirs and the understanding of the author, who is responsible for the choice of the subjects and for any omission or error. [ABSTRACT FROM AUTHOR]

The paper analyses and compares infrasonic and seismic data from snow avalanches monitored at the Vallée de la Sionne test site in Switzerland from 2009 to 2010. Using a combination of seismic and infrasound sensors, it is possible not only to detect a snow avalanche but also to distinguish between the different flow regimes and to analyse duration, average speed (for sections of the avalanche path) and avalanche size. Different sensitiveness of the seismic and infrasound sensors to the avalanche regimes is shown. Furthermore, the high amplitudes observed in the infrasound signal for one avalanche were modelled assuming that the suspension layer of the avalanche acts as a moving turbulent sound source. Our results show reproducibility for similar avalanches on the same avalanche path. [ABSTRACT FROM AUTHOR]

ALICE at the CERN LHC will investigate the physics of strongly interacting matter at extreme energy densities where the formation of the Quark Gluon Plasma is expected. Its properties can be studied from observations like the production of mesons with charm and beauty quarks. These signals have to be studied as a function of energy density, which is determined by the centrality of collisions. One of the physics observables that is closely related with the centrality of the collision is the number of spectator nucleons that can be measured by the Zero Degree Calorimeters (ZDC). Having a direct geometric interpretation allows to extract the impact parameter with minimal model assumptions. This paper describes the readout system of the ZDC. The ZDC readout consists of a VME system with a ZDC Readout Card, a VME Processor, Discriminators, a ZDC Trigger Card, scalers, QDCs and TDCs. The system was successfully tested during the 2009 ALICE data taking and is currently operational at the LHC. [ABSTRACT FROM PUBLISHER]

The ALICE High Level Trigger comprises a large computing cluster, dedicated interfaces and software applications. It allows on-line event reconstruction of the full data stream of the ALICE experiment at up to 25 GByte/s. The commissioning campaign has passed an important phase since the startup of the Large Hadron Collider in November 2009. The system has been transferred into continuous operation with focus on the event reconstruction and first simple trigger applications. The paper reports for the first time on the achieved event reconstruction performance in the ALICE central barrel region. [ABSTRACT FROM PUBLISHER]

This paper describes the performance of low energy electron reconstruction and identification at ATLAS with proton-proton collisions at a centre of mass energy of 7 TeV produced by the Large Hadron Collider. This study was performed with a sample collected from April to June 2010, corresponding to an integrated luminosity of 78 nb-1. We present the reconstruction of prompt J/ψ mesons decaying into e+e- pairs. These electrons can be used to study the detector performance at low energy, as a complement of higher energy electrons coming from W and Z decays. A sample of ~ 220 J/ψ events can be selected. Their mass values reconstructed with different inputs agree with the values expected from the initial calibration of the ATLAS detector. The kinematics and shower shape distributions (used for identification purpose) have been extracted from the J/ψ data sample and show a good agreement with the simulation. [ABSTRACT FROM AUTHOR]

Complex scientific workflows can process large amounts of data using thousands of tasks. The turnaround times of these workflows are often affected by various latencies such as the resource discovery, scheduling and data access latencies for the individual workflow processes or actors. Minimizing these latencies will improve the overall execution time of a workflow and thus lead to a more efficient and robust processing environment. In this paper, we propose a pilot job concept that has intelligent data reuse and job execution strategies to minimize the scheduling, queuing, execution and data access latencies. The results have shown that significant improvements in the overall turnaround time of a workflow can be achieved with this approach. The proposed approach has been evaluated, first using the CMS Tier0 data processing workflow, and then simulating the workflows to evaluate its effectiveness in a controlled environment. [ABSTRACT FROM AUTHOR]

The fabrication of 3D detectors which requires bulk micromachining of columnar electrodes has been realized with advancements in MEMS technology. Since the fabrication of the first 3D prototype in Stanford Nanofabrication Facility in 1997, a significant effort has been put forth to transfer the 3D detector technology to large scale manufacturing for future high luminosity collider experiments, in which the radiation hardness will be the primary concern, and other applications such as medical imaging and X-ray imaging for molecular biology. First, alternative 3D structures, single type column (STC) and double-side double type column (DDTC) 3D detectors, were produced at FBK-irst (Trento, Italy) and CNM-Barcelona (Spain), and assessed thoroughly to improve the production technology towards the standard full-3D detectors. The 3D collaboration has been extended to include SINTEF (Norway), which is committed to small to medium scale production of active edge full-3D silicon sensors. This paper focuses on p-type 3D detectors compatible with the CMS pixel front end electronics from the second run of fabrication at SINTEF clean room facilities. The sensors that passed the wafer level electrical characterization have been bump-bonded at IZM (Germany), assembled into modules and wire-bonded for functional characterization at Purdue University. We report the leakage current characteristics, bump-bond quality, threshold, noise, and gain measurement results of these 3D modules as well as the preliminary beam test data taken at Fermi National Accelerator Laboratory. [ABSTRACT FROM AUTHOR]

For the ALICE experiment at the Large Hadron Collider (LHC) at CERN/Geneva, a high level trigger system (HLT) for online event selection and data compression has been developed and a computing cluster of several hundred dual-processor nodes is being installed. A major system integration test was carried out during the commissioning of the time projection chamber (TPC), where the HLT also provides a monitoring system. All major parts like a small computing cluster, hardware input devices, the online data transportation framework, and the HLT analysis could be tested successfully. A common interface for HLT processing components has been designed to run the components from either the online or offline analysis framework without changes. The interface adapts the component to the needs of the online processing and allows the developer to use the offline framework for easy development, debugging, and benchmarking. Following this approach, results can be compared directly. For the upcoming commissioning of the whole detector, the HLT is currently prepared to run online data analysis for the main detectors, e.g., the inner tracking system (ITS), the TPC, and the transition radiation detector (TRD). The HLT processing capability is indispensable for the photon spectrometer (PHOS), where the online pulse shape analysis reduces the data volume by a factor 20. A common monitoring framework is in place and detector calibration algorithms have been ported to the HLT. The paper describes briefly the architecture of the HLT system. It focuses on typical applications and component development. [ABSTRACT FROM AUTHOR]

Measuring the properties of hailstorms is a difficult task due to the rarity and mainly small spatial extent of the events. Especially, hail observations from ground-based time-recording instruments are scarce. We present the first study of extended field observations made by a network of 80 automatic hail sensors from Switzerland. The main benefits of the sensors are the live recording of the hailstone kinetic energy and the precise timing of the impacts. Its potential limitations include a diameter-dependent dead time, which results in less than 5 % of missed impacts, and the possible recording of impacts that are not due to hail, which can be filtered using a radar reflectivity filter. We assess the robustness of the sensors' measurements by doing a statistical comparison of the sensor observations with hailpad observations, and we show that, despite their different measurement approaches, both devices measure the same hail size distributions. We then use the timing information to measure the local duration of hail events, the cumulative time distribution of impacts, and the time of the largest hailstone during a hail event. We find that 75 % of local hailfalls last just a few minutes (from less than 4.4 min to less than 7.7 min, depending on a parameter to delineate the events) and that 75 % of the impacts occur in less than 3.3 min to less than 4.7 min. This time distribution suggests that most hailstones, including the largest, fall during a first phase of high hailstone density, while a few remaining and smaller hailstones fall in a second low-density phase. [ABSTRACT FROM AUTHOR]

Summary: Many environmental and hydrological applications require knowledge about soil moisture. Its measurement accuracy is known to depend on the sensor technique, which is sensitive to soil characteristics such as texture, temperature, bulk density and salinity. However, the calibration functions provided by instrument manufacturers are generally developed under laboratory conditions, and their accuracy for field applications is rarely investigated, in particular over long time periods and in comparison with other sensors types. In this paper, four side-by-side profile soil moisture measurements down to 110cm using three low-cost sensors and one high-accuracy and high-cost time domain reflectometry (TDR) sensor are compared over a 2-year period at a clay loam site in Switzerland. The low-cost instruments include the (1) 10HS (Decagon Devices, United States), (2) CS616 (Campbell Scientific, United States), and (3) SISOMOP (SMG University of Karlsruhe, Germany) sensors, which are evaluated against the (4) TDR-based TRIME-IT/-EZ (IMKO GmbH, Germany) sensors. For the comparison, the calibration functions provided by the manufacturers are applied for each sensor type. The sensors are evaluated based on daily data regarding their representation of the volumetric water content (VWC) and its anomalies, as well as the respective temperature dependency of the measurements. Furthermore, for each sensor type the actual evapotranspiration is estimated using the soil water balance approach and compared with measurements from a weighing lysimeter. It is shown that the root mean square difference (RMSD) of VWC for the low-cost sensors compared to the TDR measurements are up to 0.3m3/m3, with highest values in near-surface layers. However, the RMSD for the VWC anomalies are lower compared to those for absolute values. We conclude that under the studied conditions none of the evaluated low-cost sensors has a level of performance consistent with the respective manufacturer specifications. Hence the derivation of site-specific calibration functions is vital for the interpretation of measurements with low-cost soil moisture sensors. Furthermore, some weaknesses of the tested low-cost sensors such as the lack of sensitivity in certain soil moisture regimes or spurious dependency on soil temperature, imply intrinsic issues with the measurements derived with this type of instruments. This is particularly critical for a number of environmental and hydrological applications, including the assessment of remote sensing measurements. [Copyright &y& Elsevier]

Abstract: The ATLAS Tile Calorimeter is a sampling detector composed by cells made of iron-scintillator tiles. The calorimeter cell signals are digitized in the front-end electronics and transmitted to the Read-Out Drivers (RODs) at the first level trigger rate. The ROD receives triggered data from up to 9856 channels and provides the energy, phase and quality factor of the signals to the second level trigger. The back-end electronics is divided into four partitions containing eight RODs each. Therefore, a total of 32 RODs are used to process and transmit the data of the TileCal detector. In order to emulate the detector signals in the production and commissioning of ROD modules a board called ROD Injector and Multiplexer Board (RIMBO) was designed. In this paper, the RIMBO main functional blocks, PCB design and the different operation modes are described. It is described the crucial role of the board within the TileCal ROD test-bench in order to emulate the front-end electronics during the validation of ROD boards as well as during the evaluation of the ROD signal reconstruction algorithms. Finally, qualification and performance results for the injection operation mode obtained during the Tile Calorimeter ROD production tests are presented. [ABSTRACT FROM AUTHOR]

Abstract: In the CMS experiment at the LHC proton–proton collider, a key role will be played by the muon system that is embedded inside the iron yoke used to close the magnetic flux of the CMS solenoid. The muon system of the CMS experiment performs three main tasks: triggering of muons, identifying muons, and assisting the central tracker in order to measure the momentum and charge of high-pt muons in the pseudorapidity region . The system is composed by a central barrel and two closing endcaps. Three independent technologies are used to reconstruct and trigger muons: Drift Tubes (DT) in the barrel, Cathode Strips Chambers (CSC) in the endcaps and Resistive Plate Chambers (RPC) in both barrel and endcap regions. All the detectors will contribute to the tracking and triggering of muons. Towards the end of 2008 and in 2009 the CMS experiment was commissioned with many millions of cosmic rays. These data have been fundamental to check the performance of the three sub-detectors and of the trigger response. In this paper the results in terms of the detection and trigger performance at the level of each sub-detector and at the level of the full muon system will be reported. [ABSTRACT FROM AUTHOR]

Abstract: Establishment of 137Cs inventories is often used to gain information on soil stability. The latter is crucial in mountain systems, where ecosystem stability is tightly connected to soil stability. In-situ measurements of 137Cs in steep alpine environments are scarce. Most studies have been carried out in arable lands and with Germanium (Ge) detectors. Sodium Iodide (NaI) detector system is an inexpensive and easy to handle field instrument, but its validity on steep alpine environments has not been tested yet. In this study, a comparison of laboratory measurements with GeLi detector and in-situ measurements with NaI detector of 137Cs gamma soil radiation has been done in an alpine catchment with high 137Cs concentration (Urseren Valley, Switzerland). The aim of this study was to calibrate the in-situ NaI detector system for application on steep alpine slopes. Replicate samples from an altitudinal transect through the Urseren Valley, measured in the laboratory with a GeLi detector, showed a large variability in 137Cs activities at a meter scale. This small-scale heterogeneity determined with the GeLi detector is smoothed out by uncollimated in-situ measurements with the NaI detector, which provides integrated estimates of 137Cs within the field of view (3.1 m2) of each measurement. There was no dependency of 137Cs on pH, clay content and carbon content, but a close relationship was determined between measured 137Cs activities and soil moisture. Thus, in-situ data must be corrected for soil moisture. Close correlation (R 2 = 0.86, p < 0.0001) was found for 137Cs activities (in Bq kg−1) estimated with in-situ (NaI detector) and laboratory (GeLi detector) methods. We thus concluded that the NaI detector system is a suitable tool for in-situ measurements in alpine environments. This paper describes the calibration of the NaI detector system for field application under elevated 137Cs activities originating from Chernobyl fallout. [Copyright &y& Elsevier]

Abstract: In this paper, we discuss luminosity measurements at Tevatron and HERA, as well as plans for luminosity measurements at LHC. We discuss luminosity measurements using the luminosity detectors of the experiments as well as measurements by the machine. We address uncertainties of the measurements, challenges and lessons learned. [Copyright &y& Elsevier]

The status of the ILC global effort is reviewed starting from the physics motivations and describing the present strategy to build such a machine and its associated detectors. Then assuming that the first significant results from LHC will soon become available, this presentation assumes four different scenarios and discuss the implications for ILC. [ABSTRACT FROM AUTHOR]

Abstract: Over the past few years, significant advancements are made in the acquisition, processing, analysis and interpretation of quantitative directional and high spectral resolution data. In particular, the broader availability of air- and spaceborne directional imaging spectrometer data supports the estimation of biophysical and -chemical variables with unprecedented accuracy and in calibrated physical units. We describe in this paper two experiments that we carried out to demonstrate regional performance of spectral and directional-based retrieval approaches in vegetated areas. In the first case study, we focus on a mountain forest located in South-Eastern Switzerland representing a boreal forest like ecosystem. DAIS7915 imaging spectrometer data have been acquired with simultaneous ground measurements. We describe the soil–vegetation–atmosphere radiative transfer using a combination of the PROSPECT, GeoSAIL, and ATCOR models. In the second case study, we acquired spectrodirectional data on ground using a field goniometer in parallel with several HyMap imaging spectrometer overflights. Both cases demonstrate conditions for the estimation of biophysical and -chemical canopy properties with reduced uncertainties by respecting the full spectral coverage and directionality of the data. We conclude that the derived canopy variables represent the actual spatial distribution of properties as they occur in the landscape. [Copyright &y& Elsevier]

More than 300 non-dispersive infrared (NDIR) CO2 low-cost sensors labelled as LP8 were integrated into sensor units and evaluated for the purpose of long-term operation in the Carbosense CO2 sensor network in Switzerland. Prior to deployment, all sensors were calibrated in a pressure and climate chamber and in ambient conditions co-located with a reference instrument. To investigate their long-term performance and to test different data processing strategies, 18 sensors were deployed at five locations equipped with a reference instrument after calibration. Their accuracy during 19 to 25 months deployment was between 8 and 12 ppm. This level of accuracy requires careful sensor calibration prior to deployment, continuous monitoring of the sensors, efficient data filtering, and a procedure to correct drifts and jumps in the sensor signal during operation. High relative humidity (> ∼85%) impairs the LP8 measurements, and corresponding data filtering results in a significant loss during humid conditions. The LP8 sensors are not suitable for the detection of small regional gradients and long-term trends. However, with careful data processing, the sensors are able to resolve CO2 changes and differences with a magnitude larger than about 30 ppm. Thereby, the sensor can resolve the site-specific CO2 signal at most locations in Switzerland. A low-power network (LPN) using LoRaWAN allowed for reliable data transmission with low energy consumption and proved to be a key element of the Carbosense low-cost sensor network. [ABSTRACT FROM AUTHOR]

Abstract: The Semi-Conductor Tracker (SCT) has been built and installed into the ATLAS detector at the Large Hadron Collider (LHC) in CERN. Together with the Pixel and Transition Radiation Tube (TRT) detectors it will provide precise tracking and vertexing information for the ATLAS Physics program. In this paper we report on the status, operational experience, and performance of the SCT in the run up to the start of the LHC. [Copyright &y& Elsevier]

The transition radiation tracker of the ATLAS setup, which is one of the two multipurpose detectors at the Large Hadron Collider (LHC), its design, and the tasks it performs are described. The tracker is fully assembled and commissioned. The first physical results obtained by the tracker in the ATLAS cosmic muon runs are presented. [ABSTRACT FROM AUTHOR]

This article presents a methodology that integrates cumulative plots with probe vehicle data for estimation of travel time statistics (average, quartile) on urban networks. The integration reduces relative deviation among the cumulative plots so that the classical analytical procedure of defining the area between the plots as the total travel time can be applied. For quartile estimation, a slicing technique is proposed. The methodology is validated with real data from Lucerne, Switzerland and it is concluded that the travel time estimates from the proposed methodology are statistically equivalent to the observed values. [ABSTRACT FROM AUTHOR]

The LHCb event-builder is implemented using a large Gigabit Ethernet network using a push-protocol for a single stage read-out at a 1 MHz event injection rate. The destination assignment and dynamic load-balancing are facilitated by LHCb's Timing and Fast Control system. The assembly of event fragments is done on each event-filter farm node instead of having dedicated builder units. The design of the event-builder will be shortly described, followed by a description of the implementation, the protocol used and the performance during first data taking. The emphasis will be on the experience we gained during the running of such a large event-building network. We will discuss the problems we encountered and how we overcame them. [ABSTRACT FROM PUBLISHER]

Automatic, synchronous and of course reliable population of the condition database is critical for the correct operation of the online selection as well as of the offline reconstruction and data analysis. We will describe here the system put in place in the CMS experiment to automate the processes to populate centrally the database and make condition data promptly available both online for the high-level trigger and offline for reconstruction. The data are “dropped” by the users in a dedicated service which synchronizes them and takes care of writing them into the online database. Then they are automatically streamed to the offline database, hence immediately accessible offline worldwide. This mechanism was intensively used during 2008 and 2009 operation with cosmic ray challenges and first LHC collision data, and many improvements were done so far. The experience of this first years of operation will be discussed in detail. [ABSTRACT FROM PUBLISHER]

The Level-1 Trigger plays a major role in the CMS experiment allowing the reduction of the raw event rate at the Large Hadron Collider. Its decision is based on information from the electromagnetic and hadronic calorimeters as well as the muon detectors. The electronics of the electromagnetic calorimeter generate and deliver basic quantities called “Trigger Primitives” which correspond to local energy deposits created by electromagnetic showers. In order to ensure the correct generation of the trigger primitives by the electronics, a special software called an emulator has been implemented. It is able to reproduce the ECAL trigger functionalities at the bit level using the same inputs and identical output format. It is configured in exactly the same way as the hardware. [ABSTRACT FROM PUBLISHER]

While the Large Hadron Collider (LHC) began taking data in 2009, scenarios for a machine upgrade to achieve a much higher luminosity are being developed. In the current planning, it is foreseen to increase the luminosity of the LHC at CERN around 2018. As radiation damage scales with integrated luminosity, the particle physics experiments will need to be equipped with a new generation of radiation hard detectors. This article reports on the status of the R&D projects on radiation hard silicon strips detectors for particle physics, linked to the Large Hadron Collider Upgrade, super-LHC (sLHC) of the ATLAS microstrip detector. The primary focus of this report is on measuring the radiation hardness of the silicon materials and the detectors under study. This involves designing silicon detectors, irradiating them to the sLHC radiation levels and studying their performance as particle detectors. The most promising silicon detector for the different radiation levels in the different regions of the ATLAS microstrip detector will be presented. Important challenges related to engineering layout, powering, cooling and reading out a very large strip detector are presented. Ideas on possible schemes for the layout and support mechanics will be shown. [ABSTRACT FROM AUTHOR]

The thermal neutron SEU cross-section of the Toshiba SRAM memory used in the LHC RadMon system was measured at different voltages. A method using the difference in its response compared to mixed particle energy field is proposed to be used as a discriminator between thermal neutron and high-energy hadron fluences. For test purposes, the proposed method was used at the CNGS and CERF facilities to estimate the field composition by counting SEUs at two different voltages and the results were compared to simulations. [ABSTRACT FROM AUTHOR]

With micro-strain resolution and the capability to sample at rates of 100 Hz and higher, fiber optic (FO) strain sensors offer exciting new possibilities for in-situ landslide monitoring. Here we describe a new FO monitoring system based on long-gauge fiber Bragg grating sensors installed at the Randa Rockslide Laboratory in southern Switzerland. The new FO monitoring system can detect sub-micrometer scale deformations in both triggered-dynamic and continuous measurements. Two types of sensors have been installed: (1) fully embedded borehole sensors and (2) surface extensometers. Dynamic measurements are triggered by sensor deformation and recorded at 100 Hz, while continuous data are logged every 5 min. Deformation time series for all sensors show displacements consistent with previous monitoring. Accelerated shortening following installation of the borehole sensors is likely related to long-term shrinkage of the grout. A number of transient signals have been observed, which in some cases were large enough to trigger rapid sampling. The combination of short- and long-term observation offers new insight into the deformation process. Accelerated surface crack opening in spring is shown to have a diurnal trend, which we attribute to the effect of snowmelt seeping into the crack void space and freezing at night to generate pressure on the crack walls. Controlled-source tests investigated the sensor response to dynamic inputs, which compared an independent measure of ground motion against the strain measured across a surface crack. Low frequency signals were comparable but the FO record suffered from aliasing, where undersampling of higher frequency signals generated spectral peaks not related to ground motion. [ABSTRACT FROM AUTHOR]

Reflectance of the urban surface is an important factor for urban climate studies and can be assessed using standard remote sensing applications. However, no application considers the three-dimensional structure of the city surface and its resulting shading patterns or the inclined roof surfaces. To determine the effect of these factors on the estimation of urban surface reflectance, a high-resolution raster-based city-surface model was used to estimate the spatial solar irradiance in an example city, namely Basel in Switzerland. Eight times daily for 1 year, the solar irradiance was calculated using MODTRAN and the illumination geometry of the city. Subsequently, the spatial distribution of the solar irradiance, as well as the error in assumed reflectance values were analysed. The error in estimation of reflectance increased with lower solar-elevation angle, so its maxima were found in winter. Higher visibility of the assumed atmosphere also increased the estimated error due to the lower proportion of diffuse irradiance. The error decreased with coarser spatial resolution of the pixel. [ABSTRACT FROM AUTHOR]

The applicability of satellite imagery products from different sensors (AVHRR-derived multi-channel sea surface temperature (MCSST), MODIS sea surface temperature (SST) products 5-Min L2 Swath 1 km and Landsat TM band 6 thermal signature) for the comprehensive monitoring of temperature and its temporal patterns over a large lake is tested in this study. The coverage of cloud-free satellite data for Lake Geneva is reported throughout a year and, more specifically, during a 13 day period in summer 2003. In a second step, we demonstrate the feasibility of the AVHRR/MODIS imagery to discern day and night temperature patterns, by generating day and night climatologies and various spatial statistics over the 13 day period. The different day and night surface thermal patterns observed by satellite imagery could be linked to the thermal structure existing in deeper water using the concept of the diurnal decoupled layer. The forcing of the persistent patterns, two warm cores divided by a saddle-shaped cold anomaly, is explained by wind periodicity and insolation conditions. The patterns can be matched to features postulated by findings of different limnologists in the past. Other surface temperature related phenomena such as water upwelling and downwelling and the occurrence of plumes are related to meteorological and hydrological events. The lakewide average lake surface water temperature (LSWT) trends for day and night during the study period are roughly parallel. A sudden loss of stored heat can be explained by episodes of long fetch, synoptic wind (bise) that interrupted the predominant breeze regime. [ABSTRACT FROM AUTHOR]

The Large Hadron Collider LHC will start operating, at CERN, Geneva, Switzerland in 2008. CMS and ATLAS are the two general purpose detectors that will collect data at the LHC. A brief overview of the ATLAS and CMS detector is given, followed by the status of the construction, installation and commissioning. Next, a quick tour on what could be the first physics measurements and search results for new physics at the LHC will be given. [ABSTRACT FROM AUTHOR]

The ALICE detector is a dedicated heavy-ion detector at the Large Hadron Collider which is commissioned end of 2007 at CERN. The ALICE triggers are handled by the Central Trigger Processor and distributed to all sub-detectors, amongst other the Time Projection Chamber and the Photon Spectrometer. The Front End Electronics of the Time Projection Chamber and the Photon Spectrometer share many of the same components. The Photon Spectrometer provides the trigger system with level 0 and level 1 triggers (e.g., high-pt photons) by the use of several Trigger Router Units and a Trigger-OR board. The trigger electronics and the Front End Electronics are situated close to the collision-point, and errors due to radiation effects are to be expected. This article will give an overview of the trigger system from trigger generation with the Photon Spectrometer to trigger reception of the Front End Electronics of both detectors. How to deal with the possible effects of the radiation environment on the electronics that do trigger handling will be evaluated. [ABSTRACT FROM AUTHOR]

Detectors and electronics inside the ATLAS detector at the large hadron collider will be exposed to high fluxes of photons, charged particles, and neutrons. Damage caused by radiation will influence the performance of the detector. It will therefore be important to continuously monitor the radiation dose to follow the level of detector degradation. It will also be important to have information about the radiation field in the detector early in the life of the experiment in order to check the simulations and to correctly predict future radiation damage. An online radiation monitoring system with semiconductor radiation sensors will monitor the dose at several locations in the ATLAS detector. It will measure ionizing dose in SiO2 with RadFETs, displacement damage in silicon in terms of 1-Me V(Si) equivalent neutron fluence with p-i-n diodes and fluence of thermal neutrons from current gain degradation in dedicated bipolar transistors. The design of the system and its response to various types of radiation is described. [ABSTRACT FROM AUTHOR]

We present the results of a global irradiation test of full size triple-GEM detectors operated with a CF4-based gas mixture. This study has been performed in the framework of an R&D activity on detectors for the innermost region of the first muon station of the LHCb experiment. The prototypes have been irradiated at the Calliope facility of the ENEA-Casaccia with a high intensity 1.25 MeV gamma from a 60Co source. After the irradiation test the detectors' performances have been measured with X-rays and with a 3 GeV pion beam at CERN. A SEM analysis on several samples of the detectors has been performed to complete the understanding of the physical processes occurring in the GEM detector during the strong irradiation [ABSTRACT FROM PUBLISHER]

The continuous wavelet transform provides a suitable tool to visualize the vertical structure of turbulence and to detect coherent structures in turbulent time series. This is demonstrated with a simple example of an artificially ramp structured time series. In this study turbulence data, i.e. the fluctuations of the horizontal wind components u′ and v′, the vertical component w′ and temperature T′, sampled with 20.83 Hz and measured simultaneously at three levels ( z/ h=1.5, 2.1 and 3.2, with z as the sensor height and h the height of the roughness elements) over an urban canopy in the inner city of Basel, Switzerland, are analyzed. The detection of the coherent structures was performed using the Mexican hat wavelet and the zero-crossing method. The analysis for unstable conditions shows that organized structures (ejection-sweep cycles) cover about 45% of the total run time. A conditional average from a total of 116 detected ejection-sweep sequences during 7 hours was calculated over a time window of 100 seconds. This dominating time scale was derived from peak frequencies of the wavelet spectra as well as from the Fourier spectra. It is shown that the normalized amplitudes of fluctuations of temperature and longitudinal wind speed during the events are largest at the lowest measurement level just above the canopy and decrease with increasing distance from the roughness elements. A comparison of related studies over different non-urban surfaces (mainly forests) shows that the shape of conditionally averaged ejection-sweep sequences is very similar for all canopies, however, the dominating time scale in general increases the rougher the surface is and the higher the roughness elements are. [ABSTRACT FROM AUTHOR]

The organization of the data collection in the parameter monitoring system of a large detector intended for experiments in particle physics is described. The work was carried out at CERN (Geneva, Switzerland) as part of the program for creating the ATLAS detector of the LHC accelerator. The detector can contain several thousand monitoring channels, and the nominal monitoring period is ∼20 s. [ABSTRACT FROM AUTHOR]

Presents a study that analyzed the radiation hardness of lasers for use in optical links of the Compact Muon Solenoid Tracker detector at the European Laboratory for Particle Physics in Geneva, Switzerland. Details of the radiation damage tests conducted; Assessment of radiation hardness assurance; Investigation of the effect of bias-enhanced annealing in irradiated AlGaAs/GaAs lasers.