Abstract
We examine the origins of azimuthal correlations observed in high energy proton-nucleus collisions by considering the simple example of the scattering of uncorrelated partons off color fields in a large nucleus. We demonstrate how the physics of fluctuating color fields in the color glass condensate (CGC) effective theory generates these azimuthal multiparticle correlations and compute the corresponding Fourier coefficients v n within different CGC approximation schemes. We discuss in detail the qualitative and quantitative differences between the different schemes. We will show how a recently introduced color field domain model that captures key features of the observed azimuthal correlations can be understood in the CGC effective theory as a model of non-Gaussian correlations in the target nucleus.
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Lappi, T., Schenke, B., Schlichting, S. et al. Tracing the origin of azimuthal gluon correlations in the color glass condensate. J. High Energ. Phys. 2016, 61 (2016). https://doi.org/10.1007/JHEP01(2016)061
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DOI: https://doi.org/10.1007/JHEP01(2016)061