Tau reconstruction at CMS with a focus on high $ p_{T} $ taus

Mapping Intimacies ◽

10.21468/scipostphysproc.1.050 ◽

2019 ◽

Author(s):

Soham Bhattacharya

Keyword(s):

Transverse Momentum ◽

High Efficiency ◽

Reconstruction Algorithm ◽

High Transverse Momentum ◽

Track Reconstruction ◽

Work In Progress ◽

Cms Experiment ◽

Pros And Cons ◽

And Performance

We present the algorithm and performance of tau reconstruction at the CMS experiment, while highlighting a dedicated reconstruction algorithm that uses calorimeter hits instead of tracks to reconstruct taus with high transverse momentum. Describing the standard Hadrons-Plus-Strips (HPS) algorithm and its dependence on track reconstruction and shower modelling, we present the calorimetric tau (calo-tau) reconstruction that uses minimal track information for high p_{T}pT taus. The pros and cons of these algorithms are discussed along with their performance and potential uses. It is found that the calo-tau algorithm outperforms the HPS algorithm in the high efficiency region. This study is work in progress, and is an attempt to tune the reconstruction for high p_{T}pT taus. The calo-tau algorithm is not yet an official tau reconstruction algorithm for CMS.

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HIGH TRANSVERSE MOMENTUM PROCESSES

Le Journal de Physique Colloques ◽

10.1051/jphyscol:1973153 ◽

1973 ◽

Vol 34 (C1) ◽

pp. C1-385-C1-399 ◽

Cited By ~ 4

Author(s):

J. D. BJORKEN

Keyword(s):

Transverse Momentum ◽

High Transverse Momentum

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Comparison between DOA Estimation Subspace methods for incoherent and coherent signals

Journal of Communications Technology Electronics and Computer Science ◽

10.22385/jctecs.v1i0.13 ◽

2015 ◽

Vol 1 ◽

pp. 18

Author(s):

Ahmed Abdalla ◽

Suhad Mohammed ◽

Tang Bin ◽

Jumma Mary Atieno ◽

Abdelazeim Abdalla

Keyword(s):

Linear Array ◽

Doa Estimation ◽

Far Field ◽

Matlab Simulation ◽

Subspace Methods ◽

Coherent Signals ◽

Uniform Linear Array ◽

Pros And Cons ◽

Basic Concepts ◽

And Performance

This paper considers the problem of estimating the direction of arrival (DOA) for the both incoherent and coherent signals from narrowband sources, located in the far field in the case of uniform linear array sensors. Three different methods are analyzed. Specifically, these methods are Music, Root-Music and ESPRIT. The pros and cons of these methods are identified and compared in light of different viewpoints. The performance of the three methods is evaluated, analytically, when possible, and by Matlab simulation. This paper can be a roadmap for beginners in understanding the basic concepts of DOA estimation issues, properties and performance.

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On Performance of Sparse Fast Fourier Transform Algorithms Using the Aliasing Filter

Electronics ◽

10.3390/electronics10091117 ◽

2021 ◽

Vol 10 (9) ◽

pp. 1117

Author(s):

Bin Li ◽

Zhikang Jiang ◽

Jie Chen

Keyword(s):

Fourier Transform ◽

Fast Fourier Transform ◽

High Efficiency ◽

Theory And Practice ◽

Long Time ◽

And Performance ◽

Binary Tree Search ◽

The One ◽

Sparse Fast Fourier Transform ◽

L1 And L2

Computing the sparse fast Fourier transform (sFFT) has emerged as a critical topic for a long time because of its high efficiency and wide practicability. More than twenty different sFFT algorithms compute discrete Fourier transform (DFT) by their unique methods so far. In order to use them properly, the urgent topic of great concern is how to analyze and evaluate the performance of these algorithms in theory and practice. This paper mainly discusses the technology and performance of sFFT algorithms using the aliasing filter. In the first part, the paper introduces the three frameworks: the one-shot framework based on the compressed sensing (CS) solver, the peeling framework based on the bipartite graph and the iterative framework based on the binary tree search. Then, we obtain the conclusion of the performance of six corresponding algorithms: the sFFT-DT1.0, sFFT-DT2.0, sFFT-DT3.0, FFAST, R-FFAST, and DSFFT algorithms in theory. In the second part, we make two categories of experiments for computing the signals of different SNRs, different lengths, and different sparsities by a standard testing platform and record the run time, the percentage of the signal sampled, and the L0, L1, and L2 errors both in the exactly sparse case and the general sparse case. The results of these performance analyses are our guide to optimize these algorithms and use them selectively.

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Advances in coupled axial turbine and nonaxisymmetric exhaust volute aerodynamics for turbomachinery

Proceedings of the Institution of Mechanical Engineers Part G Journal of Aerospace Engineering ◽

10.1177/0954410020966454 ◽

2020 ◽

pp. 095441002096645

Author(s):

Jie Gao ◽

Chunde Tao ◽

Dongchen Huo ◽

Guojie Wang

Keyword(s):

Performance Improvement ◽

High Efficiency ◽

Three Dimensional ◽

Great Influence ◽

Aerodynamic Characteristics ◽

Turbine Engines ◽

Gas Turbine Engines ◽

Axial Turbine ◽

Flow Interactions ◽

And Performance

Marine, industrial, turboprop and turboshaft gas turbine engines use nonaxisymmetric exhaust volutes for flow diffusion and pressure recovery. These processes result in a three-dimensional complex turbulent flow in the exhaust volute. The flows in the axial turbine and nonaxisymmetric exhaust volute are closely coupled and inherently unsteady, and they have a great influence on the turbine and exhaust aerodynamic characteristics. Therefore, it is very necessary to carry out research on coupled axial turbine and nonaxisymmetric exhaust volute aerodynamics, so as to provide reference for the high-efficiency turbine-volute designs. This paper summarizes and analyzes the recent advances in the field of coupled axial turbine and nonaxisymmetric exhaust volute aerodynamics for turbomachinery. This review covers the following topics that are important for turbine and volute coupled designs: (1) flow and loss characteristics of nonaxisymmetric exhaust volutes, (2) flow interactions between axial turbine and nonaxisymmetric exhaust volute, (3) improvement of turbine and volute performance within spatial limitations and (4) research methods of coupled turbine and exhaust volute aerodynamics. The emphasis is placed on the turbine-volute interactions and performance improvement. We also present our own insights regarding the current research trends and the prospects for future developments.

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A Compact Muon Tracker for Dynamic Tomography of Density Based on a Thin Time Projection Chamber with Micromegas Readout

Particles ◽

10.3390/particles4030028 ◽

2021 ◽

Vol 4 (3) ◽

pp. 333-342

Author(s):

Ignacio Lázaro Roche

Keyword(s):

Time Projection Chamber ◽

Wide Field ◽

Track Reconstruction ◽

Long Term Stability ◽

Societal Issues ◽

Primary Signal ◽

And Performance ◽

Time Projection

Tomography based on cosmic muon absorption is a rising technique because of its versatility and its consolidation as a geophysics tool over the past decade. It allows us to address major societal issues such as long-term stability of natural and man-made large infrastructures or sustainable underwater management. Traditionally, muon trackers consist of hodoscopes or multilayer detectors. For applications with challenging available volumes or the wide field of view required, a thin time projection chamber (TPC) associated with a Micromegas readout plane can provide a good tradeoff between compactness and performance. This paper details the design of such a TPC aiming at maximizing primary signal and minimizing track reconstruction artifacts. The results of the measurements performed during a case study addressing the aforementioned applications are discussed. The current works lines and perspectives of the project are also presented.

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