Nonperturbative-transverse-momentum effects and evolution in dihadron and direct photon-hadron angular correlations in p+p collisions at s =510 GeV

Research output: Contribution to journalArticle

Abstract

Dihadron and isolated direct photon-hadron angular correlations are measured in p+p collisions at s=510 GeV. Correlations of charged hadrons of 0.7<pT<10 GeV/c with π0 mesons of 4<pT<15 GeV/c or isolated direct photons of 7<pT<15 GeV/c are used to study nonperturbative effects generated by initial-state partonic transverse momentum and final-state transverse momentum from fragmentation. The nonperturbative behavior is characterized by measuring the out-of-plane transverse momentum component pout perpendicular to the axis of the trigger particle, which is the high-pT direct photon or π0. Nonperturbative evolution effects are extracted from Gaussian fits to the away-side inclusive-charged-hadron yields for different trigger-particle transverse momenta (pTtrig). The Gaussian widths and root mean square of pout are reported as a function of the interaction hard scale pTtrig to investigate possible transverse-momentum-dependent evolution differences between the π0-h± and direct photon-h± correlations and factorization breaking effects. The widths are found to decrease with pTtrig, which indicates that the Collins-Soper-Sterman soft factor is not driving the evolution with the hard scale in nearly back-to-back dihadron and direct photon-hadron production in p+p collisions. This behavior is in contrast to Drell-Yan and semi-inclusive deep-inelastic scattering measurements.

Details

Authors
  • A Adare
  • C. Aidala
  • N. N. Ajitanand
  • Y. Akiba
  • R. Akimoto
  • J J Alexander
  • M. Alfred
  • V. Andrieux
  • K. Aoki
  • N Apadula
  • Y Aramaki
  • H. Asano
  • E. T. Atomssa
  • T. C. Awes
  • Carmen Ayuso
  • B. Azmoun
  • V. Babintsev
  • M Bai
  • X. Bai
  • N. S. Bandara
  • B Bannier
  • K N Barish
  • S Bathe
  • V. Baublis
  • C. Baumann
  • S. Baumgart
  • A Bazilevsky
  • M. Beaumier
  • S. Beckman
  • R Belmont
  • A Berdnikov
  • Y. Berdnikov
  • D Black
  • D. S. Blau
  • M. Boer
  • J S Bok
  • K Boyle
  • M L Brooks
  • J. Bryslawskyj
  • H Buesching
  • V. Bumazhnov
  • Christopher C. Butler
  • S. Butsyk
  • S. Campbell
  • V. Canoa Roman
  • R. Cervantes
  • P. Christiansen
  • A. Oskarsson
  • D. Silvermyr
  • E. Stenlund
  • PHENIX Collaboration
Organisations
External organisations
  • Howard University
  • University of Colorado
  • Los Alamos National Laboratory
  • University of Michigan
  • Stony Brook University
  • RIKEN Nishina Center for Accelerator-Based Science
  • Riken BNL Research Center
  • University of Tokyo
  • High Energy Accelerator Research Organization, Tsukuba
  • Iowa State University
  • Kyoto University
  • Oak Ridge National Laboratory
  • Brookhaven National Laboratory
  • Institute for High Energy Physics, Russia
  • China Institute of Atomic Energy
  • University of Massachusetts
  • University of California, Riverside
  • Baruch College
  • Petersburg Nuclear Physics Institute (PNPI)
  • Vanderbilt University
  • St. Petersburg State Polytechnical University
  • Russian Research Center 'Kurchatov Institute'
  • New Mexico State University
  • Georgia State University
  • University of New Mexico
  • Columbia University
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Subatomic Physics
Original languageEnglish
Article number072002
JournalPhysical Review D - Particles, Fields, Gravitation and Cosmology
Volume95
Issue number7
Publication statusPublished - 2017 Apr 1
Publication categoryResearch
Peer-reviewedYes