The origin of thermal component in the transverse momentum spectra in high energy hadronic processes

Abstract

The transverse momentum spectra of hadrons produced in high energy collisions can be decomposed into two components: the exponential ("thermal") and the power ("hard") ones. Recently, the H1 Collaboration has discovered that the relative strength of these two components in Deep Inelastic Scattering depends drastically upon the global structure of the event - namely, the exponential component is absent in the diffractive events characterized by a rapidity gap. We discuss the possible origin of this effect, and speculate that it is linked to confinement. Specifically, we argue that the thermal component is due to the effective event horizon introduced by the confining string, in analogy to the Hawking-Unruh effect. In diffractive events, the $t$-channel exchange is color-singlet and there is no fragmenting string -- so the thermal component is absent. The slope of the soft component of the hadron spectrum in this picture is determined by the saturation momentum that drives the deceleration in the color field, and thus the Hawking-Unruh temperature. We analyze the data on non-diffractive $pp$ collisions and find that the slope of the thermal component of the hadron spectrum is indeed proportional to the saturation momentum.

References in corpus (10)

• Conformal collider physics: Energy and charge correlations
• Thermal Hadronization and Hawking-Unruh Radiation in QCD
• Entropy production in collisions of gravitational shock waves and of heavy ions
• The Thermal Production of Strange and Non-Strange Hadrons in e+e- Collisions
• Multi-particle Production and Thermalization in High-Energy QCD
• Production of Mesons and Baryons at High Rapidity and High Pt in Proton-Proton Collisions at sqrt(s) = 200 GeV
• Saturation and Scaling of Multiplicity, Mean p_T and p_T Distributions from 200 GeV < sqrt{s} < 7 TeV - Addendum
• Toward the AdS/CFT gravity dual for High Energy Collisions: I.Falling into the AdS
• Thermal hadron spectrum in $e^{+}{e}^{-}$ annihilation from gauge/string duality
• Role of quarks in hadroproduction in high energy collisions

Cited by in corpus (9)

• Predictions on the transverse momentum spectra for charged particle production at LHC-energies from a two component model
• Quantum Entanglement and Thermal Behavior in Charged-Current Weak Interactions
• Thermal and hard scales in transverse momentum distributions, fluctuations and entanglement
• Deconfinement and degrees of freedom in $pp$ and $A-A$ collisions at LHC energies
• Thermal radiation and inclusive production in the CGC/saturation approach at high energies
• Soft and hard scales of the transverse momentum distribution in the Color String Percolation Model
• Entropy and Heat Capacity of the transverse momentum distribution for pp collisions at RHIC and LHC energies
• Quantum Entanglement in Top Quark Pair Production
• Thermal radiation and inclusive production in the running coupling $k_T$ -- factorization approach