Download or read book Study of Double Parton Interactions in Diphoton Dijet Events in p bar p Collisions at sqrt s written by and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Double Parton Interactions in Photon 3 Jet Events in Ppbar Collisions Sqrt s written by and published by . This book was released on 2009 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt: We have used a sample of photon+3 jets events collected by the D0 experiment with an integrated luminosity of about 1 fb−1 to determine the fraction of events with double parton scattering (f{sub DP}) in a single ppbar collision at √s = 1.96 TeV. The DP fraction and effective cross section (sigma{sub eff}), a process-independent scale parameter related to the parton density inside the nucleon, are measured in three intervals of the second (ordered in p{sub T}) jet transverse momentum pT{sub jet2} within the range 15
Download or read book D0 Results on Diphoton Direct Production and Double Parton Interactions in Photon 3 Jet Events written by and published by . This book was released on 2010 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: We report the measurement of differential diphoton direct production cross sections and a study of photon + 3-jet events with double parton (DP) interactions, based on data taken with the D0 experiment at the Fermilab Tevatron proton-antiproton collider. We measure single differential cross sections as a function of the diphoton mass, the transverse momentum of the diphoton system, the azimuthal angle between the photons, and the polar scattering angle of the photons. In addition, we measure double differential cross sections considering the last three kinematic variables in three diphoton mass bins. The results are compared with different perturbative QCD predictions and event generators. We have used a sample of photon + 3-jet events collected by the D0 experiment with an integrated luminosity of about 1 fb−1 to determine the fraction of events with double parton scattering (f{sub DP}) in a single p{bar p} collision at √s = 1.96 TeV. The DP fraction and effective cross section ([sigma]{sub eff}), a process-independent scale parameter related to the parton density inside the nucleon, are measured in three intervals of the second (ordered in p{sub T}) jet transverse momentum p{sub T}{sup jet2} within the range 15
Download or read book Double Parton Scattering in p bar P Interactions at sqrt s written by and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We present the observation of doubly produced $J / \psi$ mesons as an example of processes containing a substantial fraction of double parton scattering. Measurements of the production cross sections for singly and doubly-produced $J/\psi$ mesons were done with the D0 detector at Fermilab in $p\bar{p}$ collisions at $\sqrt{s}$ = 1.96 TeV with an integrated luminosity of 8.1 fb$^{-1}$. For the first time, the double $J / \psi$ production cross section is separated into two parts: contributions from both single and double parton scattering. Lastly, this separation allowed us to determine the effective cross section [sigma]eff, a parameter related to the parton spatial density inside the hadron.
Download or read book A Study of Parton Distribution Functions with the Use of Photon Jet Event Kinematics in P bar P Collisions at radical written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We have measured the leading jet pseudorapidity distribution in photon + jet events selected from the inclusive direct photon event sample. The data are from p[bar p] collisions at [radical]s = 1.8 TeV recorded with CDF in the 1992--1993 run. This measurement has been used to study the behavior of current parton distribution sets in selected kinematic regions. The parton distribution sets CTEQ2M and MRSD0 are currently favored by this measurement.
Download or read book Study of Double Parton Scattering Using W 2 jet Events in Proton proton Collisions at sqrt s written by and published by . This book was released on 2014 with total page 45 pages. Available in PDF, EPUB and Kindle. Book excerpt: Double parton scattering is investigated in proton-proton collisions at √s = 7 TeV where the final state includes a W boson, which decays into a muon and a neutrino, and two jets. The data sample corresponds to an integrated luminosity of 5 fb-1, collected with the CMS detector at the LHC. Observables sensitive to double parton scattering are investigated after being corrected for detector effects and selection efficiencies. The fraction of W + 2-jet events due to double parton scattering is measured to be 0.055 +/- 0.002 (stat.) +/- 0.014 (syst.). Finally, the effective cross section, [sigma]eff, characterizing the effective transverse area of hard partonic interactions in collisions between protons is measured to be 20.7 +/- 0.8 (stat.) +/- 6.6 (syst.) mb.
Download or read book Multiple Parton Interactions in Ppbar Collisions in D0 Experiment at the Tevatron Collider written by and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The thesis is devoted to the study of processes with multiple parton interactions (MPI) in a ppbar collision collected by D0 detector at the Fermilab Tevatron collider at sqrt(s) = 1.96 TeV. The study includes measurements of MPI event fraction and effective cross section, a process-independent parameter related to the effective interaction region inside the nucleon. The measurements are done using events with a photon and three hadronic jets in the final state. The measured effective cross section is used to estimate background from MPI for WH production at the Tevatron energy.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 702 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Diphoton Production Rate in bar P p Collisions at square Root s written by and published by . This book was released on 1994 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: A measurement of the rate of prompt diphoton production in {bar p}p collisions at (square root)s = 1800 GeV using the CDF detector is presented. The background from non-prompt sources is estimated using a sample of single photon candidate events. The results are compared to a next-to-leading order calculation by Bailey, et al. Both background and signal take on particular significance as an indicator of our ability to estimate the backgrounds affecting LHC low mass Higgs to diphoton searches.
Download or read book Properties of Events Containing a Photon and Several Jets Seen in P bar P Collisions at square Root s written by and published by . This book was released on 1993 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt: The CDF detector is used to investigate the properties of events containing a photon and two jets. The rate of photon +2 jet production is higher than the theoretical calculation, but the shape of the events agrees with QCD predictions.
Download or read book Soft and Hard Interactions in P bar P Collisions at square Root s written by and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Proton-antiproton events collected with the CDF minimum-bias trigger at (square root)(s) = 1800 and 630 GeV are studied splitting the full event sample in a soft subsample of events with no energy clusters above 1.1 GeV and in the subsample of the remaining events. Detailed and precise analyses of the multiplicity and transverse momentum distributions as well as of the correlation of the average pt and of its dispersion with the multiplicity are performed for the two samples. Comparisons of the results and of their dependence from the center of mass energy show clear differences in their behaviors. The results support important and unexpected scaling properties of the soft sample.
Download or read book Study of Double Parton Scattering in Photon 3 Jets Final State written by You-Hao Chang and published by Springer. This book was released on 2017-01-20 with total page 107 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book mainly focuses on the study of photon + 3 jets final state in Proton-Proton Collisions at √s = 7TeV, searching for patterns of two (or more) distinct hard scatterings in the same collision, i.e the so-called Double Parton Scattering (DPS). A new method by using Monte Carlo generators was performed and provides higher order corrections to the description of the Single Parton Scattering (SPS) background. Further it is investigated whether additional contributions from DPS can improve the agreement between the measured data and the Monte Carlo predictions. The current theoretical uncertainties related to the SPS background are found to be larger than expectation. At the same time a rich set of DPS-sensitive measurements is reported for possible further interpretation.
Download or read book Multiple Parton Interaction Studies at D written by and published by . This book was released on 2016 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: Here, we present the results of studies of multiparton interactions done by the DØ collaboration using the Fermilab Tevatron at a center of mass energy of 1.96 TeV. We also present three analyses, involving three distinct final signatures: (a) a photon with at least 3 jets ([gamma] + 3jets), (b) a photon with a bottom or charm quark tagged jet and at least 2 other jets ([gamma] + b/c + 2jets), and (c) two J/ [psi] mesons. The fraction of photon + jet events initiated by double parton scattering is about 20%, while the fraction for events in which two J/ [psi] mesons were produced is 30 ± 10. While the two measurements are statistically compatible, the difference might indicate differences in the quark and gluon distribution within a nucleon. Finally, this speculation originates from the fact that photon + jet events are created by collisions with quarks in the initial states, while J/ [psi] events are produced preferentially by a gluonic initial state.
Download or read book Study of Hard Double Parton Scattering in Four jet Events in P P Collisions at s written by Orel Gueta and published by . This book was released on 2015 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Study of Parton Distribution Functions with the Use of Photon Jet Event Kinematics in Pbar P Collisions at Radicals written by 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 Searches for New Physics in Diphoton Events in p bar p Collisions at sqrt s written by and published by . This book was released on 1998 with total page 57 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Soft and Hard Interactions in P Pbar Collisions at square Root s written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Soft proton-antiproton interactions are selected from events collected with the CDF minimum-bias trigger at (square root)(s) = 1800 and 630 GeV. The analysis of their properties compared at the two energies reveals important and unexpected invariances. This paper describes an attempt to address the problem and the study of the properties of genuine soft interactions. These are identified as a subsample of proton antiproton interactions collected with the CDF minimum bias trigger. In the analysis a splitting procedure of the full minimum bias sample in two subsamples, one highly enriched in soft interactions and the other enriched in hard interactions, is applied. The two subsamples are analyzed separately through the compared measures of some inclusive distributions and final state correlations at different c.m.s. energies. The results evidence some interesting unobserved properties of the isolated soft sample and, in particular, a remarkably unpredicted invariance of some of the measured correlations and spectra between 630 and 1800 GeV.
