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Formaldehyde is a known human carcinogen and an important indoor and outdoor air pollutant. However, current strategies for formaldehyde measurement, such as chromatographic and optical techniques, are expensive and labor intensive. Low-cost gas sensors have been emerging to provide effective measurement of air pollutants. In this study, we evaluated eight low-cost electrochemical formaldehyde sensors (SFA30, Sensirion®, Staefa, Switzerland) in the laboratory with a broadband cavity-enhanced absorption spectroscopy as the reference instrument. As a group, the sensors exhibited good linearity of response (R2 > 0.95), low limit of detection (11.3 ± 2.07 ppb), good accuracy (3.96 ± 0.33 ppb and 6.2 ± 0.3% N), acceptable repeatability (3.46% averaged coefficient of variation), reasonably fast response (131–439 s) and moderate inter-sensor variability (0.551 intraclass correlation coefficient) over the formaldehyde concentration range of 0–76 ppb. We also systematically investigated the effects of temperature and relative humidity on sensor response, and the results showed that formaldehyde concentration was the most important contributor to sensor response, followed by temperature, and relative humidity. The results suggest the feasibility of using this low-cost electrochemical sensor to measure formaldehyde concentrations at relevant concentration ranges in indoor and outdoor environments. [ABSTRACT FROM AUTHOR]

The upgrade of the ATLAS detector at the Large Hadron Collider (LHC) at CERN calls for a new generation of muon detectors capable of operating in a flux of collision and background particles approximately ten times larger compared to today's conditions. We report here on the Muon ATLAS MicroMegas Activity (MAMMA) R&D project aimed at the construction of large-area spark-resistant muon chambers using the micromegas technology. [ABSTRACT FROM AUTHOR]

Abstract: The ATLAS Muon Spectrometer is designed to measure the momentum of muons with a resolution of dp/p=3% at 100GeV and 10% at 1TeV. For this task, the spectrometer employs 355,000 Monitored Drift Tubes (MDTs) arrayed in 1200 chambers. Calibration (RT) functions convert drift time measurements into tube-centered impact parameters for track segment reconstruction. RT functions depend on MDT environmental parameters and so must be appropriately calibrated for local chamber conditions. We report on the creation and application of a gas monitor system based calibration program for muon track reconstruction in the LHC startup phase. [Copyright &y& Elsevier]

Abstract: In this review paper the present state-of-the-art of muon detection systems using gaseous detectors at the Large Hadron collider (LHC) is described. Beginning with a discussion of the concepts of muon detection systems, a comparison of the various technologies used is made with respect to the challenges at present experiments, and developments for future upgrades are discussed. Starting from wire chambers, micropattern detectors are described and their readiness for upgrades is highlighted. Aging, long-term sustained operation and factors affecting gas choice are discussed. Finally some applications outside particle physics are also presented. [Copyright &y& Elsevier]

Abstract: The LHCb Outer Tracker straw tubes have shown to suffer from gain loss after irradiation in the laboratory at moderate intensities. Under irradiation an insulating layer is formed on the anode wire. The ageing is caused by contamination of the counting gas due to outgassing of the plastifier di-isopropyl-naphthalene in araldite AY103-1 used at construction. This paper presents irradiation results with and without the plastifier, together with the mass spectra of the glue samples. In addition, the effects of wire heating and large currents are presented. [Copyright &y& Elsevier]

Abstract: Resistive Plate Chambers (RPCs) are widely used in high energy physics. While avalanche mode operation is mandatory in high rate environments (ATLAS and CMS experiments at LHC), streamer mode operation is often preferred in low rate applications because of the high signal amplitude. Typical mixtures for streamer operation are composed of Argon, Tetrafluoroethane and Isobutane, with additions of SF6 below 1% to reduce the charge delivered in the gas. In this paper, results about the streamer properties observed with different mixtures are presented. [Copyright &y& Elsevier]

Abstract: The LHCb Outer Tracker (OT) detector has shown to suffer from gain loss after irradiation in the laboratory at moderate intensities. Under irradiation an insulating layer is formed on the anode wire. The ageing is caused by contamination of the counting gas due to outgassing of the glue used in construction namely araldite AY103-1. The gain loss is concentrated upstream the gas flow, and at moderate irradiation intensity only. The ageing rate is reduced by longterm flushing and by the addition of a few percent of to the gas mixture. Furthermore, applying a large positive high voltage (beyond the amplification regime) removes the insulating deposits without damaging the wire surface. This paper presents both the characteristics of the ageing phenomenon and the beneficial treatments. [Copyright &y& Elsevier]

Abstract: With the luminosity upgrade of the LHC machine (SLHC, Super-LHC), the Muon system of the ATLAS experiment at CERN will also need a detector upgrade in the highest rapidity region. MAMMA, Muon ATLAS Micromegas Activity, is an ongoing R&D activity with the aim to develop large detectors based on the bulk-Micromegas technology for use in the ATLAS Muon Spectrometer. Micromegas is a good potential candidate for the construction of large muon chambers that combine trigger and tracking capability and can sustain high particle rates expected at the SLHC. A medium size Micromegas prototype, in scale 1:10 of the final chambers, has been built and evaluated in the laboratory and in beam tests at CERN. Results from the analysis of test-beam data are presented. The results indicate that large size Micromegas is a viable candidate for ATLAS Muon upgrade [Copyright &y& Elsevier]

Abstract: The TOTEM experiment, small in size compared to the others at the LHC, is dedicated to the measurement of the total proton–proton cross-sections with a luminosity-independent method and to the study of elastic and diffractive scattering at the LHC. To achieve optimum forward coverage for charged particles emitted by the pp collisions in the IP5 interaction point, two tracking telescopes, T1 and T2, will be installed on each side in the pseudo-rapidity region between 3.1 and 6.5, and Roman Pot stations will be placed at distances of 147 and 220m from IP5. The telescope closest to the interaction point (T1, centred at z=9m) consists of Cathode Strip Chambers (CSC), while the second one (T2, centred at 13.5m), makes use of Gas Electron Multipliers (GEM). The proton detectors in the Roman Pots are silicon devices designed by TOTEM with the specific objective of reducing down to a few tens of microns the insensitive area at the edge. High efficiency as close as possible to the physical detector boundary is an essential feature. It maximizes the experimental acceptance for protons scattered elastically or interactively at polar angles down to a few micro-radians at IP5. To measure protons at the lowest possible emission angles, special beam optics have been conceived to optimize proton detection in terms of acceptance and resolution. The read-out of all TOTEM subsystems is based on the custom-developed digital VFAT chip with trigger capability. [Copyright &y& Elsevier]

Abstract: The LHCb experiment is a single arm spectrometer, designed to study CP violation in B-decays and search for new physics in rare B-decays at the large hadron collider (LHC). In such studies it is crucial to accurately and efficiently track the charged decay products in the high-density environment of the LHC. For this, the outer tracker (OT) was constructed, consisting of 55,000 straw tubes and covering an area of of module layers. The detector is foreseen to operate under large particle rates, up to 100kHz/cm per straw in the region closest to the beam. Before and during installation the detector modules and front end (FE) electronics have been extensively tested. The detector has been installed and commissioned with the help of cosmic ray events. [Copyright &y& Elsevier]

Abstract: This paper has the purpose of summarizing the present knowledge about RPCs in order to propose new ideas on how to improve their rate capability for future applications, in particular to SLHC. It will analyze the experience made in the study of ageing effects on single 2mm gap RPCs and will study the potential of thin multigap RPCs in applications where a high rate capability is required. The impact of new front end amplifiers in detecting very small charge signals will be also studied to improve the RPC performance. Different SLHC scenarios will be finally considered. [ABSTRACT FROM AUTHOR]

Abstract: The LHCb experiment is a single-arm spectrometer, designed to study B-hadron decays at the Large Hadron Collider (LHC). It is crucial to accurately and efficiently track the charged decay products with the Outer Tracker straw tube detector, in the high-density particle environment of the LHC. The Outer Tracker Front End electronics provide the precise (0.5ns) drift-time measurement, at an average occupancy of 5% and at a 1MHz trigger rate. The tracking procedure requires high-efficiency, while at the same time putting stringent limits on the noise level. The mass production and installation of 450 fully operational Front End boxes is completed. Quality checks have been performed at several stages, at the level of individual boards and at the global level with dedicated test systems mimicking the real detector and capable of simulating all the readout functionalities. An excellent overall threshold uniformity is achieved with low noise levels. [Copyright &y& Elsevier]