Class 12 NCERT Solutions - Mathematics Part I - Chapter 2 Inverse Trigonometric Functions - Exercise 2.1.Shortest Distance Between Two Lines in 3D Space | Class 12 Maths.Graphical Solution of Linear Programming Problems.Difference between write() and writelines() function in Python.Data Communication - Definition, Components, Types, Channels.How to Connect Python with SQL Database?.ISRO CS Syllabus for Scientist/Engineer Exam.ISRO CS Original Papers and Official Keys.GATE CS Original Papers and Official Keys.See also the full lists of ATLAS Conference Notes and ATLAS Physics Papers.Performance of the ATLAS Track Reconstruction Algorithms in Dense Environments in LHC Run 2 (arXiv: 1704.07983, see figures). The fitted contribution of the green distribution to the data corresponds to an inefficiency of the track reconstruction. A possible inefficiency of the track reconstruction is determined by fitting the green and blue distributions to the data (the result is shown as a red line). Three distinct distributions were created to extract the track reconstruction performance in the core of jets: isolated measurements (blue) merged measurements (green) and the data (black circles) which, due to specific selections, should resemble isolated measurements. Figure 3: The ionization energy loss (dE/dx) of charged particles in the ATLAS pixel detector. The obtained results confirm the excellent performance expected from studies on simulated data. The study uses the ionization energy loss (dE/dx), measured with the ATLAS pixel detector, to deduce the probability of failing to reconstruct a track. from data) the efficiency of reconstructing tracks in such an environment. The results also present, for the first time, a novel method for determining in situ (i.e. Recently published results give a general overview of the new track reconstruction algorithm, highlighting the ATLAS detector’s excellent performance in reconstructing charged particles in dense environments. This has maximised the potential for discovery, allowing for more detailed measurements of the newly opened kinematic regime. As a result, at angular separations between a jet and a charged particle below 0.02, the reconstruction efficiency for a charged particle track is still around 80% for jets with a transverse momentum of 1400 to 1600 GeV in simulated dijet events. Similar to increasing the magnification of a microscope, in preparation for Run 2, the ATLAS event reconstruction software was optimized to better resolve these close-by particles. This effect is exacerbated by a higher charged-particle multiplicity in the decay, as clearly visible for the tau-lepton’s decay into five charged particles (green circles). At higher transverse momentum, merged measurements are more abundant and therefore the efficiency drops. Figure 2: Efficiency to reconstruct a track of a charged particle from decays of a tau-lepton, rho-meson and B0-hadron as a function of these particles initial transverse momentum. This would result in poor identification of long-lived b-hadrons and hadronic tau decays, and difficulties in calibrating the energy and mass of jets. Therefore, without careful consideration, this can limit the track reconstruction efficiency in these dense environments. This easily creates confusion within the algorithms responsible for reconstructing charged particle trajectories (tracks). In these very energetic jets, the average separation of charged particles is comparable to the size of individual inner detector elements. These energetic collisions are prime hunting grounds for signs of new physics, including massive, hypothetical new particles that would decay to much lighter – and therefore highly boosted – bosons. The ATLAS experiment now frequently observes highly collimated bundles of particles (known as jets) with energies of up to multiple TeV, as well as tau-leptons and b-hadrons that pass through the innermost detector layers before decaying. A new age of exploration dawned at the start of Run 2 of the Large Hadron Collider, as protons began colliding at the unprecedented centre-of-mass energy of 13 TeV.
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