Test beam performance measurements for the Phase I upgrade of the CMS pixel detector

A new pixel detector for the CMS experiment was built in order to cope with the instantaneous luminosities anticipated for the Phase I Upgrade of the LHC. The new CMS pixel detector provides four-hit tracking with a reduced material budget as well as new cooling and powering schemes. A new front-end readout chip mitigates buffering and bandwidth limitations, and allows operation at low comparator thresholds. In this paper, comprehensive test beam studies are presented, which have been conducted to verify the design and to quantify the performance of the new detector assemblies in terms of tracking efficiency and spatial resolution. Under optimal conditions, the tracking efficiency is (99.95 ± 0.05) %, while the intrinsic spatial resolutions are (4.80 ± 0.25) μm and (7.99 ± 0.21) μm along the 100 μm and 150 μm pixel pitch, respectively. The findings are compared to a detailed Monte Carlo simulation of the pixel detector and good agreement is found.Peer reviewe

Velocity-space sensitivity of the time-of-flight neutron spectrometer at JET

The velocity-space sensitivities of fast-ion diagnostics are often described by so-called weight functions. Recently, we formulated weight functions showing the velocity-space sensitivity of the often dominant beam-target part of neutron energy spectra. These weight functions for neutron emission spectrometry (NES) are independent of the particular NES diagnostic. Here we apply these NES weight functions to the time-of-flight spectrometer TOFOR at JET. By taking the instrumental response function of TOFOR into account, we calculate time-of-flight NES weight functions that enable us to directly determine the velocity-space sensitivity of a given part of a measured time-of-flight spectrum from TOFOR

Relationship of edge localized mode burst times with divertor flux loop signal phase in JET

A phase relationship is identified between sequential edge localized modes (ELMs) occurrence times in a set of H-mode tokamak plasmas to the voltage measured in full flux azimuthal loops in the divertor region. We focus on plasmas in the Joint European Torus where a steady H-mode is sustained over several seconds, during which ELMs are observed in the Be II emission at the divertor. The ELMs analysed arise from intrinsic ELMing, in that there is no deliberate intent to control the ELMing process by external means. We use ELM timings derived from the Be II signal to perform direct time domain analysis of the full flux loop VLD2 and VLD3 signals, which provide a high cadence global measurement proportional to the voltage induced by changes in poloidal magnetic flux. Specifically, we examine how the time interval between pairs of successive ELMs is linked to the time-evolving phase of the full flux loop signals. Each ELM produces a clear early pulse in the full flux loop signals, whose peak time is used to condition our analysis. The arrival time of the following ELM, relative to this pulse, is found to fall into one of two categories: (i) prompt ELMs, which are directly paced by the initial response seen in the flux loop signals; and (ii) all other ELMs, which occur after the initial response of the full flux loop signals has decayed in amplitude. The times at which ELMs in category (ii) occur, relative to the first ELM of the pair, are clustered at times when the instantaneous phase of the full flux loop signal is close to its value at the time of the first ELM

P-Type Silicon Strip Sensors for the new CMS Tracker at HL-L-HC

Abstract: The upgrade of the LHC to the High-Luminosity LHC (HL-LHC) is expected to increase the LHC design luminosity by an order of magnitude. This will require silicon tracking detectors with a significantly higher radiation hardness. The CMS Tracker Collaboration has conducted an irradiation and measurement campaign to identify suitable silicon sensor materials and strip designs for the future outer tracker at the CMS experiment. Based on these results, the collaboration has chosen to use n-in-p type silicon sensors and focus further investigations on the optimization of that sensor type

Study of adsorbed water: electric potential calculation and molecular orientation in the two layer hydrate of a Mg vermiculite. [for NMR spectra interpretation]

A method is presented for calculating electric potentials in Llano and Kenya Mg vermiculite. The results are presented as equipotentials in different planes. Absolute values of electric field and orientation are given.Anglai

Détermination de la pression de vapeur de HgCl2\mathsf{_2} par la méthode d'effusion de Knudsen

The mercuric chloride (HgCl$_2$) vapor pressure was measured between 343 and 454 K by the Knudsen cell method at relatively high pressures where the flow rate is not purely molecular. Four cells with different orifice sizes were used. Knudsen equation cannot explain accurately the experimental mass loss by using molecular plus hydrodynamical equations. Calculations from our measurements were performed taking into account of an “effective radius” for our orifices, and this radius depends on the relative weight of the two contributions. We compare our results with those existing in literature.La pression de vapeur du chlorure mercurique (HgCl$_2$) a été mesurée entre 343 et 454 K par la méthode d'effusion de Knudsen pour des pressions relativement élevées où le régime d'effusion n'est pas purement moléculaire. Quatre cellules avec des orifices de différentes dimensions ont été utilisées. La somme des termes d'effusion moléculaire et hydrodynamique de l'équation de Knudsen ne permet pas de rendre compte, de façon précise, des pertes de masse expérimentales. Nous avons exploité nos mesures en attribuant à nos orifices un “rayon effectif” dépendant du poids relatif des deux termes. Nos résultats sont comparés à ceux existant dans la littérature

Geostatistical modelling of spatial distribution of balaenoptera physalus in the Northwestern Mediterranean Sea from sparse count data and heterogeneous observation efforts

International audienceObtaining accurate maps of relative abundance is an objective that may be difficult to achieve on the basis of spatially heterogeneous observation efforts and infrequent and sparse animal sightings. However, characterizing spatial distribution of wild animals such as fin whales is a major priority to protect these populations and to study their interactions with their environment.We have associated a geostatistical model with the Poisson distribution to model both spatial variation and discrete observation process. Assuming few weak hypotheses on the distribution of abundance, we have improved the experimental variogram estimate using weights that are derived from expected variances and proposed a bias correction that accounts for the variability added by the Poisson observation process. In the same way the kriging system was modified to interpolate directly the theoretical underlying animal abundance better than noisy observations from count data. For cumulative count data of fin whales over the summers 1993–2001, the method gave a map of the relative abundance which is informative on the spatial patterns. Kriging interpolation variances were dramatically reduced – ratio from 0.015 to 0.26 – compared to usual Ordinary Kriging on raw data. Adding the hypothesis of stationarity over time the variogram estimated on cumulative data can be then used with more sparser annual data

Geostatistical modelling of spatial distribution of Balenoptera physalus in the northwestern Mediterranean Sea from sparse count data and heterogeneous observation efforts

* INRA Documentation, Domaine St Paul, Site Agroparc, 84914 Avignon cedex 9 Diffusion du document : INRA Documentation, Domaine St Paul, Site Agroparc, 84914 Avignon cedex 9International audienc

Is cavus foot affected by midfoot flattening in rheumatoid arthritis?

International audienc