Constraining energy loss from high-pt azimuthal asymmetries
C. Andres,* N. Armesto, H. Niemi, R. Paatelainen, C. Salgado
*corresponding author
Pre-published on:
2019 February 20
Published on:
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Abstract
The nuclear modification factor $R_{\rm AA}$ has been satisfactorily described by various jet quenching models. Nonetheless, all these formalisms, until very recently, underpredicted the high-$p_{\rm T}$ (> 10 GeV) elliptic flow $v_2$. We find that the simultaneous description of these observables requires to strongly suppress the quenching for the first $\sim 0.6$ fm after the collision. This shows the potential of jet quenching observables to constrain the dynamics of the initial stages of the evolution.