Download or read book Jet Physics and QCD Tests at the Tevatron Collider written by Robert Plunkett and published by . This book was released on 1994 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Jet Physics and QCD Tests at the Tevatron Collider written by and published by . This book was released on 1994 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: Results are presented detailing the status of tests of perturbative QCD in hard parton-parton collisions generated by high energy collisions of protons and antiprotons at the Fermilab Collider. Recent data fro the CDF and DO experiments are compared to Next-to-Leading Order QCD calculations in hadronic jet production, prompt photon production, jet production in events with W bosons, and b-quark production.
Download or read book High P sub T Jet Physics at the Tevatron Collider written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We present results on high[ital p[sub T]] jet physics from the CDF and D[null] experiments at the Fermilab Tevatron Collider. Recent results on the inclusive jet cross-section at[radical][ital s]= 1.8 TeV will be presented and compared with QCD. We will also present results on the dijet angular distribution. Limits on quark compositeness are presented from the CDF dijet angular distribution. Finally we will discuss the results on the inclusive jet cross section at[radical][ital s]= 0.63 TeV and tests of scaling.
Download or read book Test of QCD in Multijet Final States at the Tevatron written by and published by . This book was released on 2011 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this contribution, some of the recent QCD results on jet production from the CDF and D0 experiments in Run II of the Tevatron are discussed. In particular, results include cross section measurements for dijet and trijet production, study of jet substructure and measurements of W/Z+jets cross sections. The measurements are compared with the theoretical predictions. The QCD program at the Tevatron proton-antiproton collider revolves around the jet physics. Jets are collimated sprays of hadrons generated by the fragmentation of partons originating from the hard scattering. The measurements of jets production cross section at the Tevatron provide stringent test of perturbative QCD predictions, information on the strong coupling constant, [alpha]s, and constraints on proton parton distribution functions, PDFs. The deviations from the pQCD predictions could translate into a hint of new physics. In addition, these processes form sizable backgrounds to both, the Standard Model (SM) and beyond SM physics processes. Therefore, good understanding of jets production is essential to perform precise physics measurements or searches for new physics phenomena. In this contribution, a review of some recent QCD results from the CDF [1] and D0 [2] experiments is presented. Various analyses use proton-antiproton collision data from the Fermilab Tevatron at the center of mass energy √s = 1.96 TeV corresponding to integrated luminosities of 0.7 fb−1 to 8 fb−1. The results are corrected for the experimental effects and presented at the 'particle level'. The theory predictions are corrected for the hadronization and underlying effects which are obtained from the parton shower Monte Carlo (MC) simulations.
Download or read book QCD Tests and New Physics Search with Jets at CDF written by and published by . This book was released on 1993 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: The dijet invariant mass spectrum at a center of mass energy √s = 1.8 TeV measured at the Tevatron Collider by CDF in the 1988--1989 run is presented. Comparison with leading order and next-to-leading order QCD theoretical calculation is performed. A search for a possible quark compositeness and for axigluons, while not showing evidence for new physics, allows one to put limits on the compositeness mass scale [Kappa]{sub c} and on the axigulon mass M{sub a}. Preliminary results for the inclusive jet and the total transverse energy cross section from the high statistics data collected in the present run are shown.
Download or read book H lfsb chlein f r Pflege Vereine bei Armen und Kranken written by and published by . This book was released on 1853 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Jet Physics at CDF written by and published by . This book was released on 1997 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: We present high E{sub T} jet measurements from CDF at the Fermilab Tevatron Collider. The incfilusive jet cross section at √s = 1800 GeV with - 5 times more data is compared to the published CDF results, preliminary D0 results, and next-to-leading order QCD predictions. The ∑E{sub T} cross section is also compared to QCD predictions and the dijet angular distribution is used to place a limit on quark compositeness. The inclusive jet cross section at √s = 630 GeV is compared with that at 1800 GeV to test the QCD predictions for the scaling of jet cross sections with √s. Finally, we present momentum distributions of charged particles in jets and compare them to Modified Leading Log Approximation predictions.
Download or read book QCD Results from the Fermilab Tevatron Proton antiproton Collider written by and published by . This book was released on 2010 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: Selected recent quantum chromodynamics (QCD) measurements are reviewed for Fermilab Run II Tevatron proton-antiproton collisions studied by the Collider Detector at Fermilab (CDF) and D0 Collaborations at a centre-of-mass energy of √s = 1.96 TeV. Tantamount to Rutherford scattering studies at the TeV scale, inclusive jet and dijet production cross-section measurements are used to seek and constrain new particle physics phenomena, test perturbative QCD calculations, inform parton distribution function (PDF) determinations, and extract a precise value of the strong coupling constant, a{sub s}(m{sub Z}) = 0.1161{sub -0.0048}{sup +0.0041}. Inclusive photon production cross-section measurements reveal an inability of next-to-leading-order (NLO) perturbative QCD (pQCD) calculations to describe low-energy photons arising directly in the hard scatter. Events with [gamma] + 3-jet configurations are used to measure the increasingly important double parton scattering (DPS) phenomenon, with an obtained effective interaction cross section of [sigma]{sub eff} = 16.4 ± 2.3 mb. Observations of central exclusive particle production demonstrate the viability of observing the Standard Model Higgs boson using similar techniques at the Large Hadron Collider (LHC). Three areas of inquiry into lower energy QCD, crucial to understanding high-energy collider phenomena, are discussed: the examination of intra-jet track kinematics to infer that jet formation is dominated by pQCD, and not hadronization, effects; detailed studies of the underlying event and its universality; and inclusive minimum-bias charged-particle momentum and multiplicity measurements, which are shown to challenge the Monte Carlo generators.
Download or read book A Measurement of Inclusive Jet Production at Tevatron written by Olga Norniella and published by . This book was released on 2008-09-01 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt: Quantum Chromodynamics (QCD) is the gauge theory that governs the strong interactions between quarks and gluons inside hadrons like, for example, protons and neutrons. At the Tevatron at Fermilab, protons and antiprotons collide at very high energy. In those collisions, collimated jets of hadrons are produced along the direction of struck quarks and gluons in the final state. The measurement of the inclusive jet production cross section for central jets constitutes one of the cornerstones of the jet physics program since it provides a stringent test of pQCD predictions over almost nine orders of magnitude. This Doctoral Thesis presents a measurement of the inclusive jet production cross section using the data collected by the CDF experiment in Run II. The longitudinally invariant Kt algorithm, infrared safe to all orders in pQCD, has been used in order to search for jets in the final state. This measurement is compared to pQCD NLO calculations where non-perturbative effects from the underlying event and the fragmentation of partons into jets of hadrons have been taken into account.
Download or read book Jet Physics at the Tevatron written by and published by . This book was released on 2010 with total page 29 pages. Available in PDF, EPUB and Kindle. Book excerpt: Jets have been used to verify the theory of quantum chromodynamics (QCD), measure the structure of the proton and to search for the physics beyond the Standard Model. In this article, we review the current status of jet physics at the Tevatron, a (square root)s = 1.96 TeV p{bar p} collider at the Fermi National Accelerator Laboratory. We report on recent measurements of the inclusive jet production cross section and the results of searches for physics beyond the Standard Model using jets. Dijet production measurements are also reported.
Download or read book Tevatron for LHC Report of the QCD Working Group written by R. Field and published by . This book was released on 2006 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt: The experiments at Run 2 of the Tevatron have each accumulated over 1 fb{sup -1} of high-transverse momentum data. Such a dataset allows for the first precision (i.e. comparisons between theory and experiment at the few percent level) tests of QCD at a hadron collider. While the Large Hadron Collider has been designed as a discovery machine, basic QCD analyses will still need to be performed to understand the working environment. The Tevatron-for-LHC workshop was conceived as a communication link to pass on the expertise of the Tevatron and to test new analysis ideas coming from the LHC community. The TeV4LHC QCD Working Group focused on important aspects of QCD at hadron colliders: jet definitions, extraction and use of Parton Distribution Functions, the underlying event, Monte Carlo tunes, and diffractive physics. This report summarizes some of the results achieved during this workshop.
Download or read book QCD Tests at CDF written by and published by . This book was released on 1991 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent analysis of jet data taken at the Fermilab Tevatron Collider at √S = 1.8 Tev are presented. Inclusive jet, dijet, trijet and direct photon measurements are compared to QCD parton level calculations, at orders [alpha]{sub s}3 or [alpha]{sub s}2. The large total transverse energy events are well described by the Herwig shower Montecarlo. 19 refs., 20 figs., 1 tab.
Download or read book Physics in Collision 13 written by Eike-Erik Kluge and published by Atlantica Séguier Frontières. This book was released on 1994 with total page 514 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book QCD Physics at CDF written by and published by . This book was released on 1992 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: We present measurements of jet production and isolated prompt photon production in p{bar p} collisions at √s = 1.8 TeV from the 1988--89 run of the Collider Detector at Fermilab (CDF). To test QCD with jets, the inclusive jet cross section (p{bar p} → J + X) and two jet angular distributions (p{bar P} → JJ + X) are compared to QCD predictions and are used to search for composite quarks. The ratio of the scaled jet cross sections at two Tevatron collision energies (√s= 546 and 1800 GeV) is compared to QCD predictions for X{sub T} scaling violations. Also, we present the first evidence for QCD interference effects (color coherence) in third jet production (p{bar p} → JJJ + X). To test QCD with photons, we present measurements of the transverse momentum spectrum of single isolated prompt photon production (p{bar p} → [gamma] + X), double isolated prompt photon production (p{bar p} → [gamma][gamma] + X), and the angular distribution of photon-jet events (p{bar p} → [gamma] J + X). We have also measured the isolated production ratio of [eta] and [pi]° mesons (p{bar p} → [eta] + X)/(p{bar p} → [pi]° + X) = 1.02 ± .15(stat) ± .23(sys).
Download or read book QCD Results from the Tevatron written by and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Tevatron hadron collider provides the unique opportunity to study Quantum Chromodynamics, QCD, at the highest energies. The results summarized in this talk, although representing different experimental objects, as hadronic jets and electromagnetic clusters, serve to determine the fundamental input ingredients of QCD as well as to search for new physics. The authors present results from QCD studies at the Tevatron from Run 1 data, including jet and direct photon production, and a measurement of the strong coupling constant.
Download or read book Study of Jet Properties at the Tevatron written by Mario Martinez and published by . This book was released on 2005 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Run II at the Tevatron will define a new level of precision for QCD studies in hadron collisions. Both collider experiments, CDF and D0, expect to collect up to 8 fb{sup -1} of data in this new run period. The increase in instantaneous luminosity, center-of-mass energy (from 1.8 TeV to 2 TeV) and the improved acceptance of the detectors will allow stringent tests of the Standard Model (SM) predictions in extended regions of jet transverse momentum, P{sub T}{sup jet}, and jet rapidity, Y{sup jet}. The hadronic final states in hadron-hadron collisions are characterized by the presence of soft contributions (the so-called underlying event) from initial-state gluon radiation and multiple parton interactions between remnants, in addition to the jets of hadrons originated by the hard interaction. A proper comparison with pQCD predictions at the parton level requires an adequate modeling of these soft contributions which become important at low P{sub T}{sup jet}. In this letter, a review of some of the most important QCD results from Run II is presented.
Download or read book Measurement of p bar p T bar t in the Jets Channel by the D0 Experiment at Run II of the Tevatron Collider written by and published by . This book was released on 2008 with total page 135 pages. Available in PDF, EPUB and Kindle. Book excerpt: The top quark is the heaviest and most mysterious of the known elementary particles. Therefore, careful study of its production rate and other properties is of utmost importance for modern particle physics. The Tevatron is the only facility currently capable of studying top quark properties by on-shell production. Measurement of the top quark pair production cross section is one of the major goals of the Tevatron Run II physics program. It provides an excellent test of QCD at energies exceeding 100 GeV. We report on a new measurement of p$ar{p}$ → t$ar{t}$ production at √s = 1.96 TeV using 350 pb-1 of data collected with the D0 detector between 2002 and 2005. We focus on the final state where a W boson from one of the top quarks decays into a ? lepton and its associated neutrino, while the other decays into a quark-antiquark pair. We aim to select those events in which the ? lepton subsequently decays to one or three charged hadrons, zero or more neutral hadrons and a tau neutrino (the charge conjugate processes are implied in all of the above). The observable signature thus consists of a narrow calorimeter shower with associated track(s) characteristic of a hadronic tau decay, four or more jets, of which two are initiated by b quarks accompanying the W's in the top quark decays, and a large net missing momentum in the transverse plane due to the energetic neutrino-antineutrino pair that leave no trace in the detector media. The preliminary result for the measured cross section is: ?(t$ar{t}$) = 5.1$+4.3top{-3.5}$(stat) $+0.7top{-0.7}$(syst) ± 0.3 (lumi.) pb.
