Abstract
We argue that contemporary jet substructure techniques might facilitate a more direct measurement of hard medium-induced gluon bremsstrahlung in heavy-ion collisions, and focus specifically on the “soft drop declustering” procedure that singles out the two leading jet substructures. Assuming coherent jet energy loss, we find an enhancement of the distribution of the energy fractions shared by the two substructures at small subjet energy caused by hard medium-induced gluon radiation. Departures from this approximation are discussed, in particular, the effects of colour decoherence and the contamination of the grooming procedure by soft background. Finally, we propose a complementary observable, that is the ratio of the two-pronged probability in Pb-Pb to proton-proton collisions and discuss its sensitivity to various energy loss mechanisms.
Highlights
Caused by medium-induced radiation, or dominated by direct energy injection into the thermal bath via non-perturbative drag? to what extent does the medium response to the jet propagation and fragmentation affect jet observables?
We argue that contemporary jet substructure techniques might facilitate a more direct measurement of hard medium-induced gluon bremsstrahlung in heavy-ion collisions, and focus on the “soft drop declustering” procedure that singles out the two leading jet substructures
Assuming coherent jet energy loss, we find an enhancement of the distribution of the energy fractions shared by the two substructures at small subjet energy caused by hard medium-induced gluon radiation
Summary
The splitting probability of the longitudinal energy fraction zg of a groomed jet in the vacuum [20], see [19], reads. The probability of observing a groomed jet with a single constituent given a resolution angle R0 is P1prong = ∆(R, R0), so that P1prong + P2prong = 1. These considerations are quite general and do not depend on the specific features of the grooming procedure. This is, e.g., reflected in the suppression of the inclusive jet yield and is well understood as arising mainly from large-angle multiple soft emissions This turns generally out to be a complicated task, since the probability explicitly relies on multiple emissions through the grooming procedure.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
