DSpace Collection:
http://hdl.handle.net/2440/12354
Thu, 10 Aug 2017 05:40:01 GMT2017-08-10T05:40:01ZPINGU: a vision for neutrino and particle physics at the South Pole
http://hdl.handle.net/2440/106771
Title: PINGU: a vision for neutrino and particle physics at the South Pole
Author: Aartsen, M.; Abraham, K.; Ackermann, M.; Adams, J.; Aguilar, J.; Ahlers, M.; Ahrens, M.; Altmann, D.; Andeen, K.; Anderson, T.; Ansseau, I.; Anton, G.; Archinger, M.; Arguelles, C.; Arlen, T.; Auffenberg, J.; Axani, S.; Bai, X.; Bartos, I.; Barwick, S.; et al.
Abstract: The Precision IceCube Next Generation Upgrade (PINGU) is a proposed low-energy in-fill extension to the IceCube Neutrino Observatory. With detection technology modeled closely on the successful IceCube example, PINGU will provide a 6 Mton effective mass for neutrino detection with an energy threshold of a few GeV. With an unprecedented sample of over 60 000 atmospheric neutrinos per year in this energy range, PINGU will make highly competitive measurements of neutrino oscillation parameters in an energy range over an order of magnitude higher than long-baseline neutrino beam experiments. PINGU will measure the mixing parameters ${\theta }_{23}$ and ${\rm{\Delta }}{m}_{32}^{2}$, including the octant of ${\theta }_{23}$ for a wide range of values, and determine the neutrino mass ordering at $3\sigma $ median significance within five years of operation. PINGU's high precision measurement of the rate of ${\nu }_{\tau }$ appearance will provide essential tests of the unitarity of the 3 × 3 PMNS neutrino mixing matrix. PINGU will also improve the sensitivity of searches for low mass dark matter in the Sun, use neutrino tomography to directly probe the composition of the Earth's core, and improve IceCube's sensitivity to neutrinos from Galactic supernovae. Reoptimization of the PINGU design has permitted substantial reduction in both cost and logistical requirements while delivering performance nearly identical to configurations previously studied.Sun, 01 Jan 2017 00:00:00 GMThttp://hdl.handle.net/2440/1067712017-01-01T00:00:00ZMeasurement of top quark pair differential cross sections in the dilepton channel in pp collisions at √s=7and 8 TeV with ATLAS
http://hdl.handle.net/2440/106770
Title: Measurement of top quark pair differential cross sections in the dilepton channel in pp collisions at √s=7and 8 TeV with ATLAS
Author: Aaboud, M.; ATLAS Collaboration; Aad, G.; Abbott, B.; Abdallah, J.; Abdinov, O.; Abeloos, B.; Aben, R.; Abouzeid, O.; Abraham, N.; Abramowicz, H.; Abreu, H.; Abreu, R.; Abulaiti, Y.; Acharya, B.; Adamczyk, L.; Adams, D.; Adelman, J.; Adomeit, S.; Adye, T.; et al.
Abstract: Measurements of normalized differential cross sections of top quark pair (t¯t) production are presented as a function of the mass, the transverse momentum and the rapidity of the t¯t system in proton-proton collisions at center-of-mass energies of √s=7 and 8 TeV. The data set corresponds to an integrated luminosity of 4.6 fb−1 at 7 TeV and 20.2 fb−1 at 8 TeV, recorded with the ATLAS detector at the Large Hadron Collider. Events with top quark pair signatures are selected in the dilepton final state, requiring exactly two charged leptons and at least two jets with at least one of the jets identified as likely to contain a b hadron. The measured distributions are corrected for detector effects and selection efficiency to cross sections at the parton level. The differential cross sections are compared with different Monte Carlo generators and theoretical calculations of t¯t production. The results are consistent with the majority of predictions in a wide kinematic range.
Description: Published 11 November 2016Fri, 01 Jan 2016 00:00:00 GMThttp://hdl.handle.net/2440/1067702016-01-01T00:00:00ZNucleon structure functions from operator product expansion on the lattice
http://hdl.handle.net/2440/106769
Title: Nucleon structure functions from operator product expansion on the lattice
Author: Chambers, A.; Horsley, R.; Nakamura, Y.; Perlt, H.; Rakow, P.; Schierholz, G.; Schiller, A.; Somfleth, K.; Young, R.; Zanotti, J.
Abstract: Deep-inelastic scattering, in the laboratory and on the lattice, is most instructive for understanding how the nucleon is built from quarks and gluons. The long-term goal is to compute the associated structure functions from first principles. So far this has been limited to model calculations. In this Letter we propose a new method to compute the structure functions directly from the virtual, all-encompassing Compton amplitude, utilizing the operator product expansion. This overcomes issues of renormalization and operator mixing, which so far have hindered lattice calculations of power corrections and higher moments.Sun, 01 Jan 2017 00:00:00 GMThttp://hdl.handle.net/2440/1067692017-01-01T00:00:00ZNucleon resonance structure in the finite volume of lattice QCD
http://hdl.handle.net/2440/106768
Title: Nucleon resonance structure in the finite volume of lattice QCD
Author: Wu, J.; Kamano, H.; Lee, T.; Leinweber, D.; Thomas, A.
Abstract: An approach for relating the nucleon resonances extracted from πN reaction data to lattice QCD calculations has been developed by using the finite-volume Hamiltonian method. Within models of πN reactions, bare states are introduced to parametrize the intrinsic excitations of the nucleon. We show that the resonance can be related to the probability PN∗(E) of finding the bare state, N∗, in the πN scattering states in infinite volume. We further demonstrate that the probability PVN∗(E) of finding the same bare states in the eigenfunctions of the underlying Hamiltonian in finite volume approaches PN∗(E) as the volume increases. Our findings suggest that the comparison of PN∗(E) and PVN∗(E) can be used to examine whether the nucleon resonances extracted from the πN reaction data within the dynamical models are consistent with lattice QCD calculation. We also discuss the measurement of PVN∗(E) directly from lattice QCD. The practical differences between our approach and the approach using the Lüscher formalism to relate LQCD calculations to the nucleon resonance poles embedded in the data are also discussed.Sun, 01 Jan 2017 00:00:00 GMThttp://hdl.handle.net/2440/1067682017-01-01T00:00:00Z