Sprecher
Beschreibung
The apparent tension between the absence of jet quenching in small systems and the observation of azimuthal anisotropy in the distribution of high-$p_\perp$ particles pushes for the development of new observables capable of probing different aspects of the medium formed in such collisions. With that purpose we study the formation time of jets ($\tau_f$) as a probe for early medium effects in small systems due to the loss of colour coherence (arXiv: 2510.11914). We found that jet formation time allows us to disentangle energy loss from coherence breaking, even in cases where both mechanisms would individually produce the same signal in $R_{AA}$. Furthermore, we extend this analysis by introducing the possibility of decoherence not only in the first but also in the second splitting during the parton shower development. This decoherence, present in the form of breaking of angular ordering, is also allowed to happen in a dynamical manner depending on the mean free path encountered by the parton propagating in a medium. We also study the effects of coherent scatterings on other observables such as $R_{AA}$ and $v_2$ in OO collisions and find that coherence also plays an important role there.