Characterization of the ATLAS Micromegas quadruplet prototype

A Micromegas [1] detector with four active layers, serving as prototype for the upgrade of the ATLAS muon spectrometer [2] , was designed and constructed in 2014 at CERN and represents the first example of a Micromegas quadruplet ever built. The detector has been realized using the resistive-strip technology and decoupling the amplification mesh from the readout structure. The four readout layers host overall 4096 strips with a pitch of 415μm ; two layers have strips running parallel ( η in the ATLAS reference system, for measuring the muon bending coordinate) and two layers have inclined strips by ±1.5° angle with respect to the η coordinate in order to provide measurement of the second coordinate

Construction and Performance Studies of Large Resistive Micromegas Quadruplets

In view of the use of Micromegas detectors for the upgrade of the ATLAS muon system, two detector quadruplets with an area of 0.3 m2 per plane serving as prototypes for future ATLAS chambers have been constructed. They are based on the resistive-strip technology and thus spark tolerant. The detectors were built in a modular way. The quadruplets consist of two double-sided readout panels and three support (or drift) panels equipped with the micromesh and the drift electrode. The panels are bolted together such that the detector can be opened and cleaned, if required. Two of the readout planes are equipped with readout strips inclined by 1.5 degree. In this talk, we present the results of detailed performance studies based on X-Ray and cosmic ray measurements as well as measurements with 855 MeV electrons at the MAMI accelerator. In particular, results on reconstruction efficiencies, track resolution and gain homogeneity is presented

Construction of two large-size four-plane micromegas detectors

We report on the construction and initial performance studies of two micromegas detector quadruplets with an area of 0.3 m2. They serve as prototypes for the planned upgrade project of the ATLAS muon system. Their design is based on the resistive-strip technology and thus renders the detectors spark tolerant. Each quadruplet comprises four detection layers with 1024 readout strips and a strip pitch of 415 \u3bcm. In two out of the four layers the strips are inclined by\ub11.5\ub0 to allow for the measurement of a second coordinate. We present the detector concept and report on the experience gained during the detector construction. In addition an evaluation of the detector performance with cosmic rays and test-beam data is given

Construction and Performance Studies of Large Resistive Micromegas Quadruplets

In view of the use of Micromegas detectors for the upgrade of the ATLAS muon system, two detector quadruplets with an area of 0.3 m2 per plane serving as prototypes for future ATLAS chambers have been constructed. They are based on the resistive-strip technology and thus spark tolerant. The detectors were built in a modular way. The quadruplets consist of two double-sided readout panels and three support (or drift) panels equipped with the micromesh and the drift electrode. The panels are bolted together such that the detector can be opened and cleaned, if required. Two of the readout planes are equipped with readout strips inclined by 1.5 degree. In this talk, we present the results of detailed performance studies based on X-Ray and cosmic ray measurements as well as measurements with 855 MeV electrons at the MAMI accelerator. In particular, results on reconstruction efficiencies, track resolution and gain homogeneity is presented

Construction and Performance Studies of Large Resistive Micromegas Quadruplets

Two resistive Micromegas quadruplet detectors with trapezoidal shape and an area of 0.5 m 2 were constructed, serving as prototypes for the future chambers of the ATLAS New Small Wheel (NSW) upgrade. Each quadruplet consists of two double-sided readout panels and three drift panels (one double face), equipped with a micromesh, the drift electrode and gas pipes. There are four detection layers each with an active area of 0.3 m 2 . Two layers have readout strips parallel to the base of the trapezoid while the other two have strips inclined by 1.5 with respect to the first ones. In this paper we present the first results for the performance of the detectors, in test-beam measurement and cosmic ray tests

The forward muon detector of L3

Contains fulltext : 29348.pdf (preprint version ) (Open Access

A drift chamber with a new type of straws for operation in vacuum

A 2150×2150 mm 2 registration area drift chamber capable of working in vacuum is presented. Thin-wall tubes (straws) of a new type are used in the chamber. A large share of these 9.80 mm diameter drift tubes are made in Dubna from metalized 36 µm Mylar film welded along the generatrix using an ultrasonic welding machine created at JINR. The main features of the chamber and some characteristics of the drift tubes are described. Four such chambers with the X, Y, U, V coordinates each, containing 7168 straws in total, are designed and produced at JINR and CERN. They are installed in the vacuum volume of the NA62 setup in order to study the ultra-rare decay K+→π+vv¯ and to search for and study rare meson decays. In autumn 2014 the chambers were used for the first time for the data taking in the experimental run of the NA62 at CERN׳s SPS

Precision measurement of the structure of the CMS inner tracking system using nuclear interactions

A search has been performed for heavy resonances decaying to ZZ or ZW in 2l2q final states, with two charged leptons (l = e, mu) produced by the decay of a Z boson, and two quarks produced by the decay of a W or Z boson. The analysis is sensitive to resonances with masses in the range from 400 to 4500 GeV. Two categories are defined based on the merged or resolved reconstruction of the hadronically decaying vector boson, optimized for high- and low-mass resonances, respectively. The search is based on data collected during 2016 by the CMS experiment at the LHC in proton-proton collisions with a center-of-mass energy of root s = 13 TeV, corresponding to an integrated luminosity of 35.9 fb(-1). No excess is observed in the data above the standard model background expectation. Upper limits on the production cross section of heavy, narrow spin-1 and spin-2 resonances are derived as a function of the resonance mass, and exclusion limits on the production of W' bosons and bulk graviton particles are calculated in the framework of the heavy vector triplet model and warped extra dimensions, respectively.A search has been performed for heavy resonances decaying to ZZ or ZW in 2l2q final states, with two charged leptons (l = e, mu) produced by the decay of a Z boson, and two quarks produced by the decay of a W or Z boson. The analysis is sensitive to resonances with masses in the range from 400 to 4500 GeV. Two categories are defined based on the merged or resolved reconstruction of the hadronically decaying vector boson, optimized for high- and low-mass resonances, respectively. The search is based on data collected during 2016 by the CMS experiment at the LHC in proton-proton collisions with a center-of-mass energy of root s = 13 TeV, corresponding to an integrated luminosity of 35.9 fb(-1). No excess is observed in the data above the standard model background expectation. Upper limits on the production cross section of heavy, narrow spin-1 and spin-2 resonances are derived as a function of the resonance mass, and exclusion limits on the production of W' bosons and bulk graviton particles are calculated in the framework of the heavy vector triplet model and warped extra dimensions, respectively.The structure of the CMS inner tracking system has been studied using nuclear interactions of hadrons striking its material. Data from proton-proton collisions at a center-of-mass energy of 13 TeV recorded in 2015 at the LHC are used to reconstruct millions of secondary vertices from these nuclear interactions. Precise positions of the beam pipe and the inner tracking system elements, such as the pixel detector support tube, and barrel pixel detector inner shield and support rails, are determined using these vertices. These measurements are important for detector simulations, detector upgrades, and to identify any changes in the positions of inactive elements.Peer reviewe