From R via correlations to jets – the long road to tomography

2009/06/30 by Thorsten Renk
Physics and Astronomy · #Hadron #High-Energy Particle Collisions Research #Jet (fluid) #Mechanics #Observable #Optics #Particle physics #Particle physics theoretical and experimental studies #Parton #Physics #Quantum Chromodynamics and Particle Interactions #Quantum mechanics #Statistical physics #Tomography #hep-ph

paper · pdf · doi:10.1016/j.nuclphysa.2009.10.013

published as Nucl.Phys.A830:123c-130c,2009 · 8 pages, 3 figures- To appear in the conference proceedings for Quark Matter 2009, March 30 - April 4, Knoxville, Tennessee

arxiv created 2009/09/11 · openalex publication_date 2009/11/01 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05

Abstract

The main motivation to investigate hard probes in heavy ion collisions is to do tomography, i.e. to infer medium properties from the in-medium modification of hard processes. Yet while the suppression of high P_T hadrons has been measured for some time, solid tomographic information is slow to emerge. This can be traced back to theoretical uncertainties and ambiguities in modelling both medium evolution and parton-medium interaction. Ways to overcome these difficulties are to constrain models better and to focus on more differential observables. Correlations of high P_T hadrons offer non-trivial information beyond what can be deduced from single hadron suppression. They reflect not only the hard reaction being modified by the medium, but also the back reaction of the medium to the hard probe. Models for hard back-to-back correlations are now very well constrained by a wealth of data and allow insights into the nature of the parton-medium interaction as well as first true tomographic results. Models of full in-medium jet evolution are being actively developed, but have yet to make substantial contact with data. Progress is slower in the understanding of low P_T correlations, the ridge and the cone, although a qualitative understanding of the nature of the physics behind these correlations starts to emerge.

Citations

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