Measurement of the Top Quark Mass in the Dilepton Final State Using the Matrix Element Method

Measurement of the Top Quark Mass in the Dilepton Final State Using the Matrix Element Method PDF Author: Alexander Grohsjean
Publisher: Springer Science & Business Media
ISBN: 364214070X
Category : Science
Languages : en
Pages : 155

Book Description
The main pacemakers of scienti?c research are curiosity, ingenuity, and a pinch of persistence. Equipped with these characteristics a young researcher will be s- cessful in pushing scienti?c discoveries. And there is still a lot to discover and to understand. In the course of understanding the origin and structure of matter it is now known that all matter is made up of six types of quarks. Each of these carry a different mass. But neither are the particular mass values understood nor is it known why elementary particles carry mass at all. One could perhaps accept some small generic mass value for every quark, but nature has decided differently. Two quarks are extremely light, three more have a somewhat typical mass value, but one quark is extremely massive. It is the top quark, the heaviest quark and even the heaviest elementary particle that we know, carrying a mass as large as the mass of three iron nuclei. Even though there exists no explanation of why different particle types carry certain masses, the internal consistency of the currently best theory—the standard model of particle physics—yields a relation between the masses of the top quark, the so-called W boson, and the yet unobserved Higgs particle. Therefore, when one assumes validity of the model, it is even possible to take precise measurements of the top quark mass to predict the mass of the Higgs (and potentially other yet unobserved) particles.

First Measurement of the Running of the Top Quark Mass

First Measurement of the Running of the Top Quark Mass PDF Author: Matteo M. Defranchis
Publisher: Springer Nature
ISBN: 3030903761
Category : Science
Languages : en
Pages : 170

Book Description
In this thesis, the first measurement of the running of the top quark mass is presented. This is a fundamental quantum effect that had never been studied before. Any deviation from the expected behaviour can be interpreted as a hint of the presence of physics beyond the Standard Model. All relevant aspects of the analysis are extensively described and documented. This thesis also describes a simultaneous measurement of the inclusive top quark-antiquark production cross section and the top quark mass in the simulation. The measured cross section is also used to precisely determine the values of the top quark mass and the strong coupling constant by comparing to state-of-the-art theoretical predictions. All the theoretical and experimental aspects relevant to the results presented in this thesis are discussed in the initial chapters in a concise but complete way, which makes the material accessible to a wider audience.

Measurement of the Top Quark Mass

Measurement of the Top Quark Mass PDF Author: Tzu-Chung Frank Hsieh
Publisher:
ISBN:
Category :
Languages : en
Pages : 292

Book Description


Physics at the Large Hadron Collider

Physics at the Large Hadron Collider PDF Author: Amitava Datta
Publisher: Springer Science & Business Media
ISBN: 8184892950
Category : Science
Languages : en
Pages : 260

Book Description
In an epoch when particle physics is awaiting a major step forward, the Large Hydron Collider (LHC) at CERN, Geneva will soon be operational. It will collide a beam of high energy protons with another similar beam circulation in the same 27 km tunnel but in the opposite direction, resulting in the production of many elementary particles some never created in the laboratory before. It is widely expected that the LHC will discover the Higgs boson, the particle which supposedly lends masses to all other fundamental particles. In addition, the question as to whether there is some new law of physics at such high energy is likely to be answered through this experiment. The present volume contains a collection of articles written by international experts, both theoreticians and experimentalists, from India and abroad, which aims to acquaint a non-specialist with some basic issues related to the LHC. At the same time, it is expected to be a useful, rudimentary companion of introductory exposition and technical expertise alike, and it is hoped to become unique in its kind. The fact that there is substantial Indian involvement in the entire LHC endeavour, at all levels including fabrication, physics analysis procedures as well as theoretical studies, is also amply brought out in the collection.

The Large Hadron Collider

The Large Hadron Collider PDF Author: Thomas Schörner-Sadenius
Publisher: Springer
ISBN: 3319150014
Category : Science
Languages : en
Pages : 554

Book Description
This comprehensive volume summarizes and structures the multitude of results obtained at the LHC in its first running period and draws the grand picture of today’s physics at a hadron collider. Topics covered are Standard Model measurements, Higgs and top-quark physics, flavour physics, heavy-ion physics, and searches for supersymmetry and other extensions of the Standard Model. Emphasis is placed on overview and presentation of the lessons learned. Chapters on detectors and the LHC machine and a thorough outlook into the future complement the book. The individual chapters are written by teams of expert authors working at the forefront of LHC research.

Top Quark Physics at Hadron Colliders

Top Quark Physics at Hadron Colliders PDF Author: Arnulf Quadt
Publisher: Springer Science & Business Media
ISBN: 3540710604
Category : Science
Languages : en
Pages : 166

Book Description
This will be a required acquisition text for academic libraries. More than ten years after its discovery, still relatively little is known about the top quark, the heaviest known elementary particle. This extensive survey summarizes and reviews top-quark physics based on the precision measurements at the Fermilab Tevatron Collider, as well as examining in detail the sensitivity of these experiments to new physics. Finally, the author provides an overview of top quark physics at the Large Hadron Collider.

A Measurement of the Top Quark Mass in 1.96 TeV Proton-antiproton Collisions Using a Novel Matrix Element Method

A Measurement of the Top Quark Mass in 1.96 TeV Proton-antiproton Collisions Using a Novel Matrix Element Method PDF Author: John Freeman
Publisher:
ISBN:
Category :
Languages : en
Pages : 384

Book Description


CMS Pixel Detector Upgrade and Top Quark Pole Mass Determination

CMS Pixel Detector Upgrade and Top Quark Pole Mass Determination PDF Author: Simon Spannagel
Publisher: Springer
ISBN: 331958880X
Category : Science
Languages : en
Pages : 286

Book Description
This thesis addresses two different topics, both vital for implementing modern high-energy physics experiments: detector development and data analysis. Providing a concise introduction to both the standard model of particle physics and the basic principles of semiconductor tracking detectors, it presents the first measurement of the top quark pole mass from the differential cross-section of tt+J events in the dileptonic tt decay channel. The first part focuses on the development and characterization of silicon pixel detectors. To account for the expected increase in luminosity of the Large Hadron Collider (LHC), the pixel detector of the compact muon solenoid (CMS) experiment is replaced by an upgraded detector with new front-end electronics. It presents comprehensive test beam studies conducted to verify the design and quantify the performance of the new front-end in terms of tracking efficiency and spatial resolution. Furthermore, it proposes a new cluster interpolation method, which utilizes the third central moment of the cluster charge distribution to improve the position resolution. The second part of the thesis introduces an alternative measurement of the top quark mass from the normalized differential production cross-sections of dileptonic top quark pair events with an additional jet. The energy measurement is 8TeV. Using theoretical predictions at next-to-leading order in perturbative Quantum Chromodynamics (QCD), the top quark pole mass is determined using a template fit method.

Spin Correlations in tt Events from pp Collisions

Spin Correlations in tt Events from pp Collisions PDF Author: Boris Lemmer
Publisher: Springer
ISBN: 3319189328
Category : Science
Languages : en
Pages : 246

Book Description
This thesis introduces readers to the Standard Model, the top quark and its properties, before explaining the concept of spin correlation measurement. The first measurement of top quark spin correlations at the LHC in the lepton+jets decay channel is presented. As the heaviest elementary particle, the top quark plays an essential role in the Standard Model of elementary particle physics. In the case of top quarks being produced in pairs at hadron colliders, the Standard Model predicts their spins to be correlated. The degree of correlation depends on both the production mechanism and properties of the top quark. Any deviation from the Standard Model prediction can be an indicator for new physics phenomena. The thesis employs an advanced top quark reconstruction algorithm including dedicated identification of the up- and down-type quarks from the W boson decay.

Proceedings Of The 29th International Conference On High Energy Physics: Ichep '98 (In 2 Volumes)

Proceedings Of The 29th International Conference On High Energy Physics: Ichep '98 (In 2 Volumes) PDF Author: Alan Astbury
Publisher: World Scientific
ISBN: 9814644919
Category : Science
Languages : en
Pages : 1899

Book Description
These proceedings consist of plenary rapporteur talks covering topics of major interest to the high energy physics community and parallel sessions papers which describe recent research results and future plans.