Download or read book Measurement of the Prompt Double J psi Production Cross Section in Pp Collisions at Sqrt s written by Andrew David York and published by . This book was released on 2013 with total page 205 pages. Available in PDF, EPUB and Kindle. Book excerpt: The simultaneous production of two J/psi mesons has been significantly observed in proton-proton collisions at a center-of-mass energy of 7 TeV with the CMS detector. The two J/psi mesons are fully reconstructed in their decay to muons. The signal yield is extracted with an extended maximum likelihood fit based on four event variables. A method was developed to correct for detector acceptances and efficiencies based on the measured momenta of the J/psi and their decay muons to maintain the least model dependence possible. The measurement is performed in an acceptance region defined by the individual J/psi transverse momentum and rapidity. From the measured signal yield of 446 events corresponding to an integrated luminosity of 4:7 inverse femtobarn. The total cross section is found to be 1:49 nanobarn, with 0:07 statistical and 0:13 nb systematic error, and unpolarizaed production was assumed. Most predictions for particle production at the LHC assume dominance of single parton interaction for proton-proton collisions, which can be tested with the final state measured in this analysis. The differential cross section is measured in bins of the double J/psi invariant mass, the double J/psi transverse momentum, and the absolute difference in rapidity of the two J/psi. The reconstruction of the four charged muon trajectories heavily relies on the Pixel subdetector located close to the beampipe. Systematic studies with cosmic muons and tracks from collision events are presented. The development of the Pixel RawToDigi package, data quality monitoring packages, commissioning studies of Pixel data and tracks in first collisions, and realistic simulations of decay signals in the pixel subdetector were all performed as a part of this dissertation work.
Download or read book Double J J psi production written by S. P. Baranov and published by . This book was released on 1993 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Double J psi production written by Sergej P. Baranov and published by . This book was released on 1993 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Observation and Studies of Double J psi Production at the Tevatron written by and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We present the observation of doubly-produced $J/\psi$ mesons with the D0 detector at Fermilab in $p\bar{p}$ collisions at $\sqrt{s}=1.96$ TeV. The production cross section for both singly and doubly-produced $J/\psi$ mesons is measured using a sample with an integrated luminosity of 8.1fb$^{-1}$. For the first time, the double $J/\psi$ production cross section is separated into contributions due to single and double parton scatterings. Using these measurements, we determine the effective cross section $\sigma_{eff}$, a parameter characterizing an effective spatial area of the parton-parton interactions and related to the parton spatial density inside the nucleon.
Download or read book Double J y63 J psi production written by Sergej P. Baranov and published by . This book was released on 1993 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Double spin Asymmetry of J psi Production in Polarized Pp collisions at HERA N written by O. V. Terjaev and published by . This book was released on 1996 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Measurement of the Prompt J Psi Pair Production Cross Section in Pp Collisions at Sqrt s written by Grant Valentine Riley and published by . This book was released on 2017 with total page 141 pages. Available in PDF, EPUB and Kindle. Book excerpt: The cross section for the prompt production of [J/Psi] meson pairs in proton-proton collisions at √ s[sqrt(s)] = 8 TeV at the LHC from a sample corresponding to an integrated luminosity of 20.2±0.5 fb−1 [inverse femtobarns] has been measured with the CMS detector. It provides unique insight into particle production and proton structure in proton-proton (pp) collisions. The two [J/Psi] mesons are fully reconstructed in their [mu+ mu-] decay. An acceptance region is defined by the individual [J/Psi] transverse momentum p [J/Psi pT] and rapidity y [J/Psi Rapidity]. The total fiducial cross section assuming unpolarized prompt [J/Psi] pair production is found to be [sigma_fid] = 195.7 ± 11.1 (stat) ± 22.1 (syst) ± 5.1 (lumi) ± 2.3 (BF) pb. The differential cross sections for prompt [J/Psi] pair production within this acceptance region are measured in eight event variables. Most predictions for particle production in pp collisions at the LHC assume dominance of single parton (gluon, quark) interactions (SPS) at the leading order perturbation theory. This assumption is tested with the final state measured in this analysis. Significant contributions from next-to-leading order processes and double parton scattering (DPS) are observed. In addition, the single [J/Psi] production cross section is estimated from theory and measured with pp collision data. Single [J/Psi] production is compared to the pair production via DPS and quantified via an effective cross section. This quantity is further compared to several particle pair production processes. In particular, the [J/Psi] pair production probes the contributions of gluons. All particle production measurements with CMS depend on the precise knowledge of the LHC luminosity. A detector, the Pixel Luminosity Telescope, based on solid state technology is used to count charged particle tracks from pp collisions, a measure of the instantaneous luminosity. The measurement is provided online for every crossing of the LHC beams. Tests of sensors and the development work for the detector are presented.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 380 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
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 Measurement of the J J psi Cross Section and Double Spin Asymmetries in Vector Meson Production in Polarised Lepton Nucleon Scattering at HERMES written by Falk Meißner and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Measurement of the J y63 J psi Cross Section and Double Spin Asymmetries in Vector Meson Production in Polarised Lepton Nucleon Scattering at HERMES written by Falk Meißner and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Study of Double Parton Scattering Using Four Jet Scenarios written by Paolo Gunnellini and published by Springer. This book was released on 2015-08-24 with total page 290 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis addresses in a very new and elegant way several measurements and the extraction of so-called double parton scattering. The new and elegant way lies in the combination of measurements and a very smart extraction of double parton scattering results, which is easy to apply and overcomes many of the technical difficulties of older methods. Many new phenomena in particle physics can be observed when particles are collided at the highest energies; one of the highlights in recent years was the discovery of the Higgs boson at the Large Hadron Collider at CERN. Understanding the production mechanism of the Higgs boson at the LHC requires detailed knowledge of the physics of proton-proton collisions. When the density of partons in the protons becomes large, there is a non-negligible probability that more than one parton participates in the interaction and the so-called double parton scattering becomes important. In some cases very particular final state signatures can be observed, which can be regarded as an indication of such double partonic scattering and where the different interactions can be separated. Such multiple partonic interactions play an important role when precise predictions from known processes are required.
Download or read book Measurement of the J y63 J psi Cross Section and Double Spin Asymmetries in Vector Meson Production in Polarised Lepton Nucleon Scattering at HERMES written by Falk Meißner and published by . This book was released on 2000 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Government Reports Announcements Index written by and published by . This book was released on 1995 with total page 938 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Multiple Parton Interactions at the LHC written by Paolo Bartalini and published by World Scientific Publishing. This book was released on 2018-11-08 with total page 472 pages. Available in PDF, EPUB and Kindle. Book excerpt: Many high-energy collider experiments (including the current Large Hadron Collider at CERN) involve the collision of hadrons. Hadrons are composite particles consisting of partons (quarks and gluons), and this means that in any hadron–hadron collision there will typically be multiple collisions of the constituents — i.e. multiple parton interactions (MPI). Understanding the nature of the MPI is important in terms of searching for new physics in the products of the scatters, and also in its own right to gain a greater understanding of hadron structure. This book aims at providing a pedagogical introduction and a comprehensive review of different research lines linked by an involvement of MPI phenomena. It is written by pioneers as well as young leading scientists, and reviews both experimental findings and theoretical developments, discussing also the remaining open issues.
Download or read book High Energy Physics Index written by and published by . This book was released on 1993 with total page 600 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Government Reports Annual Index written by and published by . This book was released on 1994 with total page 1688 pages. Available in PDF, EPUB and Kindle. Book excerpt:
