Breakdown of QCD factorization at large Feynman x

Abstract

Recent measurements by the BRAHMS collaboration of high-pT hadron production at forward rapidities at RHIC found the relative production rate(d-Au)/(p-p) to be suppressed, rather than enhanced. Examining other known reactions (forward production of light hadrons, the Drell-Yan process, heavy flavor production, etc.), one notes that all of these display a similar property, namely, their cross sections in nuclei are suppressed at large xF. Since this is the region where x2 is minimal, it is tempting to interpret this as a manifestation of coherence, or of a color glass condensate, whereas it is actually a simple consequence of energy conservation and takes place even at low energies. We demonstrate that in all these reactions there is a common suppression mechanism that can be viewed, alternatively, as a consequence of a reduced survival probability for large rapidity gap processes in nuclei, Sudakov suppression, an enhanced resolution of higher Fock states by nuclei, or an effective energy loss that rises linearly with energy. Our calculations agree with data.

12 pages Latex, 8 figures (only technical corrections in the replacement)

References in corpus (40)

• New Generation of Parton Distributions with Uncertainties from Global QCD Analysis
• Computing Quark and Gluon Distribution Functions for Very Large Nuclei
• Gluon Distribution Functions for Very Large Nuclei at Small Transverse Momentum
• Radiative energy loss and $p_{\perp }$-broadening of high energy partons in nuclei
• Saturation Effects in Deep Inelastic Scattering at low $Q^2$ and its Implications on Diffraction
• Radiative energy loss of high energy quarks and gluons in a finite volume quark-gluon plasma
• Gluon production in current-nucleus and nucleon-nucleus collisions in a quasi-classical approximation
• Evolution of the nuclear modification factors with rapidity and centrality in d+Au collisions at $\sqrt{s_{NN}} = 200 GeV
• Nuclear parton distributions at next to leading order
• Measurement of Differences Between J/Psi and Psi' Suppression in p-A Collisions
• Nuclear Modification Factor in d+Au Collisions: Onset of Suppression in the Color Glass Condensate
• Field strength correlators in full QCD
• Nonperturbative Effects in Gluon Radiation and Photoproduction of Quark Pairs
• Bremsstrahlung of a Quark Propagating through a Nucleus
• Parton energy loss limits and shadowing in Drell-Yan dimuon production
• Cronin Effect in Hadron Production off Nuclei
• Coherence Phenomena in Charmonium Production off Nuclei at the Energies of RHIC and LHC
• Nuclear Hadronization: Within or Without?
• A Bound on the Energy Loss of Partons in Nuclei
• Gluon Shadowing and Heavy Flavor Production off Nuclei
• The Drell-Yan Process and Factorization in Impact Parameter Space
• Nuclear effects in the Drell-Yan process at very high energies
• Nuclear Shadowing and Coherence Length for Longitudinal and Transverse Photons
• Broadening of Transverse Momentum of Partons Propagating through a Medium
• Saturation and shadowing in high-energy proton-nucleus dilepton production
• The color dipole picture of the Drell-Yan process
• Fragmentation functions from semi-inclusive DIS pion production and implications for the polarized parton densities
• Transparent Nuclei and Deuteron-Gold Collisions at RHIC
• Energy Loss versus Shadowing in the Drell-Yan Reaction on Nuclei
• Nonperturbative Gluon Radiation and Energy Dependence of Elastic Scattering
• The survival probability of large rapidity gaps in a three channel model
• Soft QCD Dynamics of Elastic Scattering in Impact Parameter Representation
• Energy loss of fast quarks in nuclei
• Understanding the Non-Perturbative Deep-Inelastic Scattering: Instanton-induced Inelastic Dipole-Dipole Cross Section
• General Issues in Small-x and Diffractive Physics
• Electroproduction of Charmonia off Nuclei
• $J/\psi$ production and nuclear effects for d+Au and p+p collisions in PHENIX
• Small Gluonic Spots in the Nucleon: Searching for Signatures in Data
• Electroproduction of vector mesons off nuclei at ELFE: exact solution for color transparency
• Scanning the Quark-Gluon Plasma with Charmonium

Cited by in corpus (84)

• A Large Hadron Electron Collider at CERN: Report on the Physics and Design Concepts for Machine and Detector
• Saturation Physics and Deuteron--Gold Collisions at RHIC
• Thermal Dileptons at LHC
• Heavy-Quark Kinetics in the QGP at LHC
• The Color Glass Condensate and hadron production in the forward region
• Heavy Ion Collisions at the LHC - Last Call for Predictions
• Inclusive Hadron Productions in pA Collisions
• Distribution Functions of the Nucleon and Pion in the Valence Region
• Heavy-quarkonium suppression in p-A collisions from parton energy loss in cold QCD matter
• Azimuthal correlations of forward di-hadrons in d+Au collisions at RHIC in the Color Glass Condensate
• CGC predictions for p+Pb collisions at the LHC
• Electron Ion Collider: The Next QCD Frontier - Understanding the glue that binds us all
• Single Inclusive Hadron Production at RHIC and the LHC from the Color Glass Condensate
• Forward Neutral Pion Production in p+p and d+Au Collisions at sqrt(s_NN)=200 GeV
• Non-Abelian energy loss in cold nuclear matter
• Centrality and rapidity dependence of inclusive jet production in $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV proton-lead collisions with the ATLAS detector
• Phenomenological Review on Quark-Gluon Plasma: Concepts vs. Observations
• Mining for Gluon Saturation at Colliders
• J/psi Production and Nuclear Effects for d+Au and p+p Collisions at sqrt(s_NN) = 200 GeV
• J/psi suppression in p-A collisions from parton energy loss in cold QCD matter
• High Gluon Densities in Heavy Ions Collisions
• Revisiting scaling properties of medium-induced gluon radiation
• A possible determination of the quark radiation length in cold nuclear matter
• Forward di-hadron back-to-back correlations in $\mathbf{pA}$ collisions from rcBK evolution
• Hadron production in pA collisions at the LHC from the Color Glass Condensate
• Diffractive Higgs Production from Intrinsic Heavy Flavors in the Proton
• Open charm tomography of cold nuclear matter
• Quarkonium Physics at a Fixed-Target Experiment using the LHC Beams
• Single Spin Asymmetry Scaling in the Forward Rapidity Region at RHIC
• Drell-Yan production and Lam-Tung relation in the Color Glass Condensate formalism
• Initial-state cold nuclear matter energy loss effects on inclusive jet production in p+A collisions at RHIC and LHC
• Quarkonium production in high energy proton-proton and proton-nucleus collisions
• Scaling properties of high p_T inclusive hadron production
• The initial state of heavy-ion collisions
• Could saturation effects be visible in a future electron-ion collider?
• Hadrons and direct photon in pp and pA collisions at LHC and saturation effects
• Quenching of high-pT hadrons: Energy Loss vs Color Transparency
• Centrality, Rapidity and Transverse-Momentum Dependence of Cold Nuclear Matter Effects on J/Psi Production in d+Au, Cu+Cu and Au+Au Collisions at sqrt(s_NN)=200 GeV
• Direct photons at forward rapidities in high-energy pp collisions
• Inclusive heavy flavor jet production with semi-inclusive jet functions: from proton to heavy-ion collisions
• Looking for intrinsic charm in the forward region at BNL RHIC and CERN LHC
• Heavy flavor production in high-energy $pp$ collisions: color dipole description
• Parton energy loss in high energy hard forward processes in proton-nucleus collisions
• Diffractive Excitation of Heavy Flavors: Leading Twist Mechanisms
• Impact of fully coherent energy loss on heavy meson production in pA collisions
• Mapping the dominant regions of the phase space associated with $c\bar{c}$ production relevant for the Prompt Atmospheric Neutrino Flux
• Study of Nuclear Suppression at Large Forward Rapidities in d-Au Collisions at Relativistic and Ultrarelativistic Energies
• Charged Pion Production in p+C Collisions at 158 GeV/c Beam Momentum: Discussion
• Suppression vs enhancement of heavy quarkonia in pA collisions
• Consequences of high-$x$ proton size fluctuations in small collision systems at RHIC
• Heavy quarkonium production: Nontrivial transition from pA to AA collisions
• RHIC Results on J/Psi
• Nuclear effects in Drell-Yan pair production in high-energy $pA$ collisions
• Puzzles of J/Psi production off nuclei
• Final state interactions and hadron quenching in cold nuclear matter
• Fully coherent energy loss effects on light hadron production in pA collisions
• Gluon Shadowing in DIS off Nuclei
• Cronin effect for protons and pions in pA collisions
• Quantum-mechanical description of in-medium fragmentation
• Unitarity bound for gluon shadowing
• Initial-state splitting kernels in cold nuclear matter
• Cronin effect in the Drell-Yan reaction
• Hard hadronic diffraction is not hard
• CGC and initial state effects in Heavy Ion Collisions
• Diffractive Bremsstrahlung in Hadronic Collisions
• Single and double inclusive particle production in d+Au collisions at RHIC, leading twist and beyond
• Initial State: Theory Status
• Drell-Yan process in $pA$ collisions: the exact treatment of coherence effects
• A heuristic description of high-pT hadron production in heavy ion collisions
• Proton and anti-proton production in the forward region of d+Au collisions at RHIC from the color glass condensate
• Estimations for the Single Diffractive production of the Higgs boson at the Tevatron and the LHC
• Breakdown of kT-factorization and J/Psi production in dA collisions
• Quarkonia production at RHIC
• Strangeness production in high-multiplicity events
• $J/\psi$ production in PHENIX
• Review of Forward Physics at RHIC
• Physics with Nuclei at an Electron Ion Collider
• Heavy Flavor and Jets at RHIC
• Physics of Large-x Nuclear Suppression
• Quenching of high-pT hadrons: a non-energy-loss scenario
• Nuclear Suppression of Dileptons at Large xF
• Testing the CGC in proton-lead collisions at the LHC
• Nuclear suppression of dileptons at forward rapidities
• Energy dependence of nuclear effects in hadron-nucleus collisions