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arXiv · 1407.0326

Angular structure of the in-medium QCD cascade

Jean-Paul Blaizot·Yacine Mehtar-Tani·Marcus A. C. Torres
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Abstract

We study the angular broadening of a medium-induced QCD cascade. We derive the equation that governs the evolution of the average transverse momentum squared of the gluons in the cascade as a function of the medium length, and we solve this equation analytically. Two regimes are identified. For a medium of a not too large size, and for not too soft gluons, the transverse momentum grows with the size of the medium according to standard momentum broadening. The other regime, visible for a medium of a sufficiently large size and very soft gluons, is a regime dominated by multiple branchings: there, the average transverse momentum saturates to a value that is independent of the size of the medium. This structure of the in-medium QCD cascade is, at least qualitatively, compatible with the recent data on dijet asymmetry.

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Jean-Paul Blaizot, Yacine Mehtar-Tani, Marcus A. C. Torres. 2014-07-01. Angular structure of the in-medium QCD cascade. https://doi.org/10.1103/physrevlett.114.222002

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