Revealing proton shape fluctuations with incoherent diffraction at high energy

Abstract

The differential cross section of exclusive diffractive vector meson production in electron proton collisions carries important information on the geometric structure of the proton. More specifically, the coherent cross section as a function of the transferred transverse momentum is sensitive to the size of the proton, while the incoherent, or proton dissociative cross section is sensitive to fluctuations of the gluon distribution in coordinate space. We show that at high energies the experimentally measured coherent and incoherent cross sections for the production of $J/\Psi$ mesons are very well reproduced within the color glass condensate framework when strong geometric fluctuations of the gluon distribution in the proton are included. For $\rho$ meson production we also find reasonable agreement. We study in detail the dependence of our results on various model parameters, including the average proton shape, analyze the effect of saturation scale and color charge fluctuations and constrain the degree of geometric fluctuations.

16 pages, 17 figures. v2: new references and clarifications, published in PRD

References in corpus (19)

• The Color Glass Condensate
• High-precision determination of the electric and magnetic form factors of the proton
• Event-by-event gluon multiplicity, energy density and eccentricities at RHIC and LHC
• Analysis of combined HERA data in the Impact-Parameter dependent Saturation model
• Azimuthal correlations of forward di-hadrons in d+Au collisions at RHIC in the Color Glass Condensate
• Eccentric protons? Sensitivity of flow to system size and shape in p+p, p+Pb and Pb+Pb collisions
• Comprehensive description of $J/\psi$ production in proton-proton collisions at collider energies
• Wilson line correlator in the MV model: relating the glasma to deep inelastic scattering
• Exclusive J/$\psi$ photoproduction off protons in ultra-peripheral p-Pb collisions at $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV
• The RMS Charge Radius of the Proton and Zemach Moments
• J/Psi production in ultraperipheral Pb+Pb and p+Pb collisions at energies available at the CERN Large Hadron Collider
• Forward dihadron correlations in deuteron-gold collisions with a Gaussian approximation of JIMWLK
• Exclusive diffractive processes in electron-ion collisions
• Nuclear enhancement and suppression of diffractive structure functions at high energies
• Forward $J/\psi$ production in proton-nucleus collisions at high energy
• The shape of the proton at high energies
• Evidence for color fluctuations in the nucleon in high-energy scattering
• Ballistic protons in incoherent exclusive vector meson production as a measure of rare parton fluctuations at an Electron-Ion Collider
• On parton number fluctuations at various stages of the rapidity evolution

Cited by in corpus (17)

• Imprints of fluctuating proton shapes on flow in proton-lead collisions at the LHC
• Mining for Gluon Saturation at Colliders
• Collectivity and electromagnetic radiation in small systems
• Energy dependence of dissociative $J/\psi$ photoproduction as a signature of gluon saturation at the LHC
• Diffractive Dijet Production and Wigner Distributions from the Color Glass Condensate
• Investigating saturation effects in ultraperipheral collisions at the LHC with the color dipole model
• Accessing the gluonic structure of light nuclei at the Electron Ion Collider
• Ballistic diffusion of heavy quarks in the early stage of relativistic heavy ion collisions at RHIC and LHC
• Quark and gluon entanglement in the proton on the light cone at intermediate $x$
• Coherent and incoherent vector meson electroproduction in the future electron-ion colliders: the hot-spot predictions
• Diffractive excitation in $pp$ and $pA$ collisions at high energies
• Exclusive processes in $ep$ collisions at the EIC and LHeC: A closer look on the predictions of saturation models
• Collective flow and hydrodynamics in large and small systems at the LHC
• Initial conditions of bulk matter in ultrarelativistic nuclear collisions
• New opportunities at the photon energy frontier
• Evolution of eccentricities induced by geometrical and quantum fluctuations in proton-nucleus collisions
• Proton structure fluctuations: constraints from HERA and applications to p+A collisions