The central feature of the CMS Link alignment system is a network of Amorphous Silicon Position Detectors distributed throughout the muon spectrometer that are connected by multiple laser lines. The ...data collected during the years from 2008 to 2015 is presented confirming an outstanding performance of the photo sensors during more than seven years of operation. Details of the photo sensor readout of the laser signals are presented. The mechanical motions of the CMS detector are monitored using these photosensors and good agreement with distance sensors is obtained.
Magnet Cycles and Stability Periods of the CMS Experiment are studied with the Alignment Link System data recorded along the 2008–2013 years of operation. The motions of the mechanical structures due ...to the magnetic field forces are studied and the mechanical stability of the detector during the physics data taking periods is verified.
The hadronic part of the electron structure function F2e has been measured for the first time, using e+e− data collected by the DELPHI experiment at LEP, at centre-of-mass energies of ...s=91.2–209.5 GeV. The data analysis is simpler than that of the measurement of the photon structure function. The electron structure function F2e data are compared to predictions of phenomenological models based on the photon structure function. It is shown that the contribution of large target photon virtualities is significant. The data presented can serve as a cross-check of the photon structure function F2γ analyses and help in refining existing parameterisations.
A study of the photo-response behaviour of carbon-doped hydrogenated amorphous silicon photo-detectors over 2800h of continuous illumination with white light is presented. Both direct and inverse ...Staebler–Wronski effects are observed in the data.
This document presents an application of the new generation of amorphous silicon position detecting (ASPD) sensors to multipoint alignment. Twelve units are monitored along a 20
m long laser beam, ...where the light path is deflected by 90° using a pentaprism.
Approaching LHC data taking, the CMS experiment is deploying, commissioning and operating the building tools of its grid-based computing infrastructure. The commissioning program includes testing, ...deployment and operation of various storage solutions to support the computing workflows of the experiment. Recently, some of the Tier-1 and Tier-2 centers supporting the collaboration have started to deploy StoRM based storage systems. These are POSIX-based disk storage systems on top of which StoRM implements the Storage Resource Manager (SRM) version 2 interface allowing for a standard-based access from the Grid. In this notes we briefly describe the experience so far achieved at the CNAF Tier-1 center and at the IFCA Tier-2 center.
Different LEP experiments have measured
P
τ
, with good precision using inclusive methods, without decay identification, both in the case of single tau and correlation measurements. Each of these ...methods will reach a precision Δ
P
τ
0.015 (Δ sin
2
θ
w
0.002) at the end of LEP I in each of the four experiments.
Abstract A search for new long-lived particles decaying to leptons using proton–proton collision data produced by the CERN LHC at $$\sqrt{s}=13\,\text {Te}\text {V} $$ s = 13 Te is presented. Events ...are selected with two leptons (an electron and a muon, two electrons, or two muons) that both have transverse impact parameter values between 0.01 and 10 $$\,\text {cm}$$ cm and are not required to form a common vertex. Data used for the analysis were collected with the CMS detector in 2016, 2017, and 2018, and correspond to an integrated luminosity of 118 (113) $$\,\text {fb}^{-1}$$ fb - 1 in the $${{\mathrm{e}}_{\mathrm{}}^{\mathrm{}}} {{\mathrm{e}}_{\mathrm{}}^{\mathrm{}}} $$ e e channel ( $${{\mathrm{e}}_{\mathrm{}}^{\mathrm{}}} {\upmu } $$ e μ and $${\upmu } {\upmu } $$ μ μ channels). The search is designed to be sensitive to a wide range of models with displaced $${{\mathrm{e}}_{\mathrm{}}^{\mathrm{}}} {\upmu } $$ e μ , $${{\mathrm{e}}_{\mathrm{}}^{\mathrm{}}} {{\mathrm{e}}_{\mathrm{}}^{\mathrm{}}} $$ e e , and $${\upmu } {\upmu } $$ μ μ final states. The results constrain several well-motivated models involving new long-lived particles that decay to displaced leptons. For some areas of the available phase space, these are the most stringent constraints to date.
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