Performance of the CMS Missing Transverse Momentum Reconstruction in Pp Data at $\sqrt{s}$

Performance of the CMS Missing Transverse Momentum Reconstruction in Pp Data at $\sqrt{s}$ PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 55

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Book Description
The performance of missing transverse energy reconstruction algorithms is presented by our team using√s=8 TeV proton-proton (pp) data collected with the CMS detector. Events with anomalous missing transverse energy are studied, and the performance of algorithms used to identify and remove these events is presented. The scale and resolution for missing transverse energy, including the effects of multiple pp interactions (pileup), are measured using events with an identified Z boson or isolated photon, and are found to be well described by the simulation. Novel missing transverse energy reconstruction algorithms developed specifically to mitigate the effects of large numbers of pileup interactions on the missing transverse energy resolution are presented. These algorithms significantly reduce the dependence of the missing transverse energy resolution on pileup interactions. Furthermore, an algorithm that provides an estimate of the significance of the missing transverse energy is presented, which is used to estimate the compatibility of the reconstructed missing transverse energy with a zero nominal value.

Performance of the CMS Missing Transverse Momentum Reconstruction in Pp Data at $\sqrt{s}$

Performance of the CMS Missing Transverse Momentum Reconstruction in Pp Data at $\sqrt{s}$ PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 55

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Book Description
The performance of missing transverse energy reconstruction algorithms is presented by our team using√s=8 TeV proton-proton (pp) data collected with the CMS detector. Events with anomalous missing transverse energy are studied, and the performance of algorithms used to identify and remove these events is presented. The scale and resolution for missing transverse energy, including the effects of multiple pp interactions (pileup), are measured using events with an identified Z boson or isolated photon, and are found to be well described by the simulation. Novel missing transverse energy reconstruction algorithms developed specifically to mitigate the effects of large numbers of pileup interactions on the missing transverse energy resolution are presented. These algorithms significantly reduce the dependence of the missing transverse energy resolution on pileup interactions. Furthermore, an algorithm that provides an estimate of the significance of the missing transverse energy is presented, which is used to estimate the compatibility of the reconstructed missing transverse energy with a zero nominal value.

Measurement of the Top Quark Mass in the Dileptonic Decay Channel at CMS

Measurement of the Top Quark Mass in the Dileptonic Decay Channel at CMS PDF Author: Nathan Mirman
Publisher:
ISBN:
Category :
Languages : en
Pages : 390

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Book Description
This dissertation presents a measurement of the top quark mass (Mt) in the dileptonic decay channel using data from proton-proton collisions at sqrt(s) = 8 TeV recorded by the CMS experiment at the LHC, corresponding to an integrated luminosity of 19.7 ± 0.5 fb-1. The analysis is based on three observables whose distributions are sensitive to the value of Mt. The Mbl invariant mass and MT2 'stransverse mass' observables are employed in a simultaneous fit to determine the value of Mt and an overall jet energy scale factor (JSF). In a complementary approach, the MT2-assisted on-shell reconstruction technique is used to construct an Mblv invariant mass observable that is combined with MT2 to measure Mt. The shapes of the observables, along with their evolutions in Mt and JSF, are modeled by a non-parametric Gaussian process regression technique. The sensitivity of the observables to the value of Mt is investigated using a Fisher information density function. The top quark mass is measured to be 172.22 ± 0.18 (stat) ± 0.91 (syst) GeV. This dissertation also presents a missing transverse momentum (MET) significance variable, which is used to estimate the compatibility of the reconstructed MET with a zero nominal value. This variable may be used to discriminate between events containing real MET due to undetected particles and spurious MET due to object misreconstruction, finite detector resolution, or detector noise. The MET significance variable is tuned using data-driven techniques, and its performance is evaluated using the CMS Run 1 and Run 2 datasets. ...

Looking Inside Jets

Looking Inside Jets PDF Author: Simone Marzani
Publisher: Springer
ISBN: 3030157091
Category : Science
Languages : en
Pages : 205

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Book Description
This concise primer reviews the latest developments in the field of jets. Jets are collinear sprays of hadrons produced in very high-energy collisions, e.g. at the LHC or at a future hadron collider. They are essential to and ubiquitous in experimental analyses, making their study crucial. At present LHC energies and beyond, massive particles around the electroweak scale are frequently produced with transverse momenta that are much larger than their mass, i.e., boosted. The decay products of such boosted massive objects tend to occupy only a relatively small and confined area of the detector and are observed as a single jet. Jets hence arise from many different sources and it is important to be able to distinguish the rare events with boosted resonances from the large backgrounds originating from Quantum Chromodynamics (QCD). This requires familiarity with the internal properties of jets, such as their different radiation patterns, a field broadly known as jet substructure. This set of notes begins by providing a phenomenological motivation, explaining why the study of jets and their substructure is of particular importance for the current and future program of the LHC, followed by a brief but insightful introduction to QCD and to hadron-collider phenomenology. The next section introduces jets as complex objects constructed from a sequential recombination algorithm. In this context some experimental aspects are also reviewed. Since jet substructure calculations are multi-scale problems that call for all-order treatments (resummations), the bases of such calculations are discussed for simple jet quantities. With these QCD and jet physics ingredients in hand, readers can then dig into jet substructure itself. Accordingly, these notes first highlight the main concepts behind substructure techniques and introduce a list of the main jet substructure tools that have been used over the past decade. Analytic calculations are then provided for several families of tools, the goal being to identify their key characteristics. In closing, the book provides an overview of LHC searches and measurements where jet substructure techniques are used, reviews the main take-home messages, and outlines future perspectives.

The Eightfold Way

The Eightfold Way PDF Author: Murray Gell-mann
Publisher: CRC Press
ISBN: 0429976240
Category : Science
Languages : en
Pages : 331

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Book Description
This monograph presents thirty research papers dealing with the classification of strongly interacting particles and their interaction according to the eightfold way. In each chapter the authors' commentary introduces the reprints.

Heavy Neutral Particle Decays to Tau Pairs

Heavy Neutral Particle Decays to Tau Pairs PDF Author: Michail Bachtis
Publisher: Springer Science & Business Media
ISBN: 3319032577
Category : Science
Languages : en
Pages : 161

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Book Description
The work presented in this thesis spans a wide range of experimental particle physics subjects, starting from level-1 trigger electronics to the final results of the search for Higgs boson decay and to tau lepton pairs. The thesis describes an innovative reconstruction algorithm for tau decays and details how it was instrumental in providing a measurement of Z decay to tau lepton pairs. The reliability of the analysis is fully established by this measurement before the Higgs boson decay to tau lepton pairs is considered. The work described here continues to serve as a model for analysing CMS Higgs to tau leptons measurements.

Engineering of Scintillation Materials and Radiation Technologies

Engineering of Scintillation Materials and Radiation Technologies PDF Author: Mikhail Korzhik
Publisher: Springer Nature
ISBN: 3030219704
Category : Science
Languages : en
Pages : 326

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Book Description
This proceedings book presents dual approaches to examining new theoretical models and their applicability in the search for new scintillation materials and, ultimately, the development of industrial technologies. The ISMART conferences bring together the radiation detector community, from fundamental research scientists to applied physics experts, engineers, and experts on the implementation of advanced solutions. This scientific forum builds a bridge between the different parts of the community and is the basis for multidisciplinary, cooperative research and development efforts. The main goals of the conference series are to review the latest results in scintillator development, from theory to applications, and to arrive at a deeper understanding of fundamental processes, as well as to discover components for the production of new generations of scintillation materials. The book highlights recent findings and hypotheses, key advances, as well as exotic detector designs and solutions, and includes papers on the microtheory of scintillation and the initial phase of luminescence development, applications of the various materials, as well as the development and characterization of ionizing radiation detection equipment. It also touches on the increased demand for cryogenic scintillators, the renaissance of garnet materials for scintillator applications, nano-structuring in scintillator development, trends in and applications for security, and exploration of hydrocarbons and ecological monitoring.

Encyclopedia of Solid Earth Geophysics

Encyclopedia of Solid Earth Geophysics PDF Author: Harsh Gupta
Publisher: Springer Science & Business Media
ISBN: 904818701X
Category : Science
Languages : en
Pages : 1579

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Book Description
The past few decades have witnessed the growth of the Earth Sciences in the pursuit of knowledge and understanding of the planet that we live on. This development addresses the challenging endeavor to enrich human lives with the bounties of Nature as well as to preserve the planet for the generations to come. Solid Earth Geophysics aspires to define and quantify the internal structure and processes of the Earth in terms of the principles of physics and forms the intrinsic framework, which other allied disciplines utilize for more specific investigations. The first edition of the Encyclopedia of Solid Earth Geophysics was published in 1989 by Van Nostrand Reinhold publishing company. More than two decades later, this new volume, edited by Prof. Harsh K. Gupta, represents a thoroughly revised and expanded reference work. It brings together more than 200 articles covering established and new concepts of Geophysics across the various sub-disciplines such as Gravity, Geodesy, Geomagnetism, Seismology, Seismics, Deep Earth Processes, Plate Tectonics, Thermal Domains, Computational Methods, etc. in a systematic and consistent format and standard. It is an authoritative and current reference source with extraordinary width of scope. It draws its unique strength from the expert contributions of editors and authors across the globe. It is designed to serve as a valuable and cherished source of information for current and future generations of professionals.

Handbook of Signal Processing Systems

Handbook of Signal Processing Systems PDF Author: Shuvra S. Bhattacharyya
Publisher: Springer Science & Business Media
ISBN: 1461468590
Category : Technology & Engineering
Languages : en
Pages : 1395

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Book Description
Handbook of Signal Processing Systems is organized in three parts. The first part motivates representative applications that drive and apply state-of-the art methods for design and implementation of signal processing systems; the second part discusses architectures for implementing these applications; the third part focuses on compilers and simulation tools, describes models of computation and their associated design tools and methodologies. This handbook is an essential tool for professionals in many fields and researchers of all levels.

XXII DAE High Energy Physics Symposium

XXII DAE High Energy Physics Symposium PDF Author: Md. Naimuddin
Publisher: Springer
ISBN: 3319731718
Category : Science
Languages : en
Pages : 879

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Book Description
These proceedings gather invited and contributed talks presented at the XXII DAE-BRNS High Energy Physics (HEP) Symposium, which was held at the University of Delhi, India, on 12–16 December 2016. The contributions cover a variety of topics in particle physics, astroparticle physics, cosmology and related areas from both experimental and theoretical perspectives, namely (1) Neutrino Physics, (2) Standard Model Physics (including Electroweak, Flavour Physics), (3) Beyond Standard Model Physics, (4) Heavy Ion Physics & QCD (Quantum Chromodynamics), (5) Particle Astrophysics & Cosmology, (6) Future Experiments and Detector Development, (7) Formal Theory, and (8) Societal Applications: Medical Physics, Imaging, etc. The DAE-BRNS High Energy Physics Symposium, widely considered to be one of the leading symposiums in the field of Elementary Particle Physics, is held every other year in India and supported by the Board of Research in Nuclear Sciences (BRNS), Department of Atomic Energy (DAE), India. As many as 400 physicists and researchers attended the 22nd Symposium to discuss the latest advances in the field. A poster session was also organized to highlight the work and findings of young researchers. Bringing together the essential content, the book offers a valuable resource for both beginning and advanced researchers in the field.

Heavy Flavours

Heavy Flavours PDF Author: A J Buras
Publisher: World Scientific
ISBN: 9814602825
Category :
Languages : en
Pages : 803

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Book Description
This volume is a collection of review articles on the most outstanding topics in heavy flavour physics. All the authors have made significant contributions to this field. The book reviews in detail the theoretical structure of heavy flavour physics within the Standard Model and its confrontation with existing experimental data.The physics of the top quark and of the Higgs play an important role in this volume. Beginning with radiative electroweak corrections and their impressive tests at LEP and hadron colliders, the book summarizes the present status of quark mixing, CP violation and rare decays. The dynamics of exclusive D- and B-meson decays, the τ-lepton physics and the newly discovered heavy quark symmetries are discussed in detail. The impact of strong interactions on weak decays is clearly visible in many articles. The physics of heavy flavours at LEP, HERA and hadron colliders constitutes an important part of the book. Another significant topic is the possible role of heavy flavours in the spontaneous symmetry breaking of gauge symmetries. Finally the most recent advances in lattice calculations of the properties of heavy flavours and the lattice studies of the dynamics of heavy flavours are presented.