ZYAM and ${\mathbf{v}}_2$: Underestimating jet yields from dihadron azimuth correlations

Abstract

Dihadron azimuth correlations can provide combinatoric access to jet structure in nuclear collisions. To isolate true jet yields a background must be subtracted, including a constant offset and a contribution from "elliptic flow" (azimuth quadrupole measured by $v_2^2$). The principle of "zero yield at minimum" (ZYAM) has been introduced to determine the constant offset. Independent measurements determine $v_2^2$. This analysis demonstrates that the ZYAM concept is invalid (offset typically overestimated) and $v_2^2$ is also overestimated by conventional measurements. Jet yields are thus substantially underestimated in more-central A-A collisions, and the "away-side" azimuth peak (back-to-back jet correlations) is strongly distorted, leading to incorrect inference of "Mach shocks."

14 pages, 11 figures

References in corpus (8)

• Dihadron azimuthal correlations in Au+Au collisions at sqrt(s_NN)=200 GeV
• Core-Corona Separation in Ultra-Relativistic Heavy Ion Collisions
• Indications of Conical Emission of Charged Hadrons at the BNL Relativistic Heavy Ion Collider
• Evolution of minimum-bias parton fragmentation in nuclear collisions
• Universal Centrality and Collision Energy Trends for $v_2$ Measurements From 2D Angular Correlations
• Azimuth quadrupole component spectra on transverse rapidity ${\mathbf{y}}_{\mathbf{t}}$ for identified hadrons from Au-Au collisions at $\sqrt{s_{NN}}=$ 200 GeV
• The RHIC azimuth quadrupole: "perfect liquid" or gluonic radiation?
• The azimuth structure of nuclear collisions -- I

Cited by in corpus (23)

• Particle-yield modification in jet-like azimuthal di-hadron correlations in Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 2.76 TeV
• Azimuthal di-hadron correlations in d+Au and Au+Au collisions at $\sqrt{s_{NN}}=200$ GeV from STAR
• Anomalous centrality evolution of two-particle angular correlations from Au-Au collisions at $\sqrt{s_{\mathrm{NN}}}$ = 62 and 200 GeV
• Parton fragment yields derived from minimum-bias jet angular correlations
• System size and energy dependence of near-side di-hadron correlations
• Is hydrodynamics relevant to RHIC collisions?
• CCharge-multiplicity dependence of single-particle transverse-rapidity ${\mathbf{y}}_{\mathbf{t}}$ and pseudorapidity $\eta$ densities and 2D angular correlations from 200 GeV $p$-$p$ collisions
• A critical review of RHIC experimental results
• Comparing the same-side "ridge" in CMS p-p angular correlations to RHIC p-p data
• Dijet production, collision centrality and backgrounds in high-energy p-p collisions
• On the presence of nonjet "higher harmonic" components in 2D angular correlations from high energy heavy ion collisions
• Gluon correlations from a Glasma flux-tube model compared to measured hadron correlations on transverse momentum $({\mathbf{p}}_{\mathbf{t}},{\mathbf{p}}_{\mathbf{t}})$ and angular differences $({\eta }_{\mathbf{\Delta }},{\varphi }_{\mathbf{\Delta }})$
• K${}_{\mathrm{S}}^0$- and (anti-)$\Lambda$-hadron correlations in pp collisions at $\sqrt{s}=13$ TeV
• Measurement of Two-Particle Correlations of Hadrons in $e^{+}{e}^{-}$ Collisions at Belle
• Two-component model of 2D trigger-associated hadron correlations on rapidity space ${\mathbf{y}}_{\mathbf{ta}}\times {\mathbf{y}}_{\mathbf{tt}}$ derived from 1D ${\mathbf{p}}_{\mathbf{t}}$ spectra for p-p collisions at $\sqrt{\mathbf{s}}=200$ GeV
• Correction methods for finite-acceptance effects in two-particle correlation analyses
• Two-particle transverse momentum correlations in pp and p-Pb collisions at energies available at the CERN Large Hadron Collider
• Optimal modeling of 1D azimuth correlations in the context of Bayesian inference
• Jet-like correlations with respect to K${}_{\mathrm{S}}^0$ and $\Lambda$ ($\bar{\Lambda }$) in pp and central Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 5.02 TeV
• Comparing the PYTHIA Monte Carlo to a two-component (soft + hard) model of hadron production in high-energy p-p collisions
• Energy Dependance of Azimuthal Correlations (and more) in Nucleus-Nucleus Collisions at the CERN SPS
• Investigating Sources of Angular Correlations at High pT in Nucleon-Nucleon and Nucleus-Nucleus Collisions at the CERN SPS
• The "soft ridge" - is it initial-state geometry or modified jets?