Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download D-Zero Top Quark Mass Analysis PDF full book. Access full book title D-Zero Top Quark Mass Analysis by . Download full books in PDF and EPUB format.
Author: Publisher: ISBN: Category : Languages : en Pages :
Book Description
I report on D[null]'s preliminary analyses of the top quark mass[ital m[sub t]] based on an exposure at[radical]s= 1.8 TeV with integrated luminosity[approx]100 pb[sup -1] at the Fermilab Tevatron[ital p][ital[anti p]] collider. From three[ital e]+[mu]+[>=] 2 jet events (with background 0.36[+-] 0.09), using partly original methods, we obtain[ital m[sub t]]= 158[+-] 24(stat)[+-] 10(syst) GeV/c[sup 2]. From 30[ital e] or[mu]+[+-]4 jets events (with background 17.4[+-]2.2), we find[ital m[sub t]]= 170[+-] 15(stat)[+-] 10(syst) GeV/c[sup 2]. Recently, using multivariate methods based on particular kinematic variables, we have learned how to improve the background suppression in the latter sample without unduly distorting the reconstructed top mass spectra. Applying these methods should improve considerably the accuracy of our top quark mass determination.
Author: Publisher: ISBN: Category : Languages : en Pages :
Book Description
I report on D[null]'s preliminary analyses of the top quark mass[ital m[sub t]] based on an exposure at[radical]s= 1.8 TeV with integrated luminosity[approx]100 pb[sup -1] at the Fermilab Tevatron[ital p][ital[anti p]] collider. From three[ital e]+[mu]+[>=] 2 jet events (with background 0.36[+-] 0.09), using partly original methods, we obtain[ital m[sub t]]= 158[+-] 24(stat)[+-] 10(syst) GeV/c[sup 2]. From 30[ital e] or[mu]+[+-]4 jets events (with background 17.4[+-]2.2), we find[ital m[sub t]]= 170[+-] 15(stat)[+-] 10(syst) GeV/c[sup 2]. Recently, using multivariate methods based on particular kinematic variables, we have learned how to improve the background suppression in the latter sample without unduly distorting the reconstructed top mass spectra. Applying these methods should improve considerably the accuracy of our top quark mass determination.
Author: Kent W. Staley Publisher: Cambridge University Press ISBN: 9780521827102 Category : Philosophy Languages : en Pages : 366
Book Description
The Evidence for the Top Quark offers both a historical and philosophical perspective on an important recent discovery in particle physics: the first evidence for the elementary particle known as the top quark. Drawing on published reports, oral histories, and internal documents from the large collaboration that performed the experiment, Kent Staley explores in detail the controversies and politics that surrounded this major scientific result.At the same time the book seeks to defend an objective theory of scientific evidence based on error probabilities.
Author: Publisher: ISBN: Category : Languages : en Pages : 8
Book Description
Recent results on top quark physics with the D0 experiment in {anti p}p collisions at √s = 1.8 TeV for an integrated luminosity of 125 pb−1 are reported. The direct measurement of the top quark mass uses single lepton events, giving the result m{sub top} = 173.3 ± 5.6(stat) ± 6.2(syst) GeV=c2. The measurement of the t{anti t} production cross section includes analyses from 8 top decay channels: dilepton (t{anti t} → e[mu], ee, and [mu][mu]), electron and neutrino (t{anti t} → e[nu]), and single leptons (t{anti t} → e + jets and t{anti t} → [mu] + jets) with and without b tagging. We measure the t{anti t} production cross section to be 5.5 ± 1.8 pb at m{sub top} = 173.3 GeV/c2.
Author: Publisher: ISBN: Category : Languages : en Pages : 5
Book Description
The authors describe three recent results from D0 related to the top quark: a preliminary measurement of the t{bar t} spin correlation in top quark pair production, a search for top quark decays into charged Higgs bosons, and an improved cross section analysis in the t{bar t} → e[mu] channel using neural networks.
Author: Publisher: ISBN: Category : Languages : en Pages : 214
Book Description
The top quark is a very special fundamental particle in the Standard Model (SM) mainly due to its heavy mass. The top quark has extremely short lifetime and decays before hadronization. This reduces the complexity for the measurement of its mass. The top quark couples very strongly to the Higgs boson since the fermion-Higgs Yukawa coupling linearly depends on the fermion's mass. Therefore, the top quark is also heavily involved in Higgs production and related study. A precise measurement of the top quark mass is very important, as it allows for self-consistency check of the SM, and also gives a insight about the stability of our universe in the SM context. This dissertation presents my work on the measurement of the top quark mass in dilepton final states of t$\bar{t}$ events in p$\bar{p}$ collisions at √s = 1.96 TeV, using the full DØ Run II data corresponding to an integrated luminosity of 9.7 fb-1 at the Fermilab Tevatron. I extracted the top quark mass by reconstructing event kinematics, and integrating over expected neutrino rapidity distributions to obtain solutions over a scanned range of top quark mass hypotheses. The analysis features a comprehensive optimization that I made to minimize the expected statistical uncertainty. I also improve the calibration of jets in dilepton events by using the calibration determined in t$\bar{t}$ → lepton+jets events, which reduces the otherwise limiting systematic uncertainty from the jet energy scale. The measured mass is 173.11 ± 1.34(stat)+0.83 -0.72(sys) GeV .
Author: Publisher: ISBN: Category : Languages : en Pages :
Book Description
CDF and D0 have published or submitted for publication eleven papers [1-11] that include direct experimental measurements of the top quark mass. Each experiment has found that the lepton+jets channel [1,5,6,9,10,11,12] gives the most precise result. However, CDF and D0 have also measured the top quark mass in other decay topologies. Both D0 [2,6] and CDF [3,4] have published additional results in the dilepton channels, while CDF [8] has published a result in the all-hadronic channel. Our aim in this note is to reduce the overall uncertainty on the top quark mass measurement by combining the most recent and final of these measurements [1,2,3,7,8]. This note combines the mass from the five separate measurements taking into account the statistical and systematic uncertainties as well as the correlations in the systematic uncertainties. The final Tevatron top mass based on Run 1 data is m{sub t} = 174.3 " 3.2(stat) " 4.0(syst) GeV/c2. Combining the statistical and systematic uncertainties, the top mass is m{sub t} = 174.3 " 5.1 GeV/c2.
Author: Publisher: ISBN: Category : Languages : en Pages :
Book Description
I summarize recent top quark physics results from the Fermilab Tevatron experiments. Since the observation of the top quark by CDF and D[null] in 1995, the experimental focus has shifted to a detailed study of the top quark's properties. This article describes recent measurements of the top quark production cross section, mass, kinematic properties, branching ratios, V[sub[ital tb]], and the[ital W] polarization in top decays.
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.
Author: 
Author: 
Author: Kent W. Staley
Author: 
Author: 
Author: 
Author: 
Author: 
Author: 
Author: Alexander Grohsjean
Author: