Speaker
Description
Measurements of hard probes in $e^{+}e^{-}$ collision data are essential components of parallel studies of hard probes in proton-proton and heavy-ion collisions as $e^{+}e^{-}$ collisions offer a true reference for such systems free from any hadronic initial state effects. Recently, one class of hard-probe observables that has seen a resurgence of interest for studying vacuum QCD are the projected N-point energy correlation function (ENCs) of particles within jets. This is primarily due to a clear separation of scales these observables provide, which is useful for studying both perturbative and non-perturbative QCD in the collinear limit. An analogous class of observables can be used to study QCD in the back-to-back (Sudakov) limit, but in hadronic collisions, such studies have additional experimental difficulties. In this talk, we will discuss recent ENC measurements from Archived ALEPH $e^{+}e^{-}$ data taken at LEP at $\sqrt{s} = 91.2$ GeV spanning, for the first time, both the collinear to the back-to-back limit of QCD as well as the transition between these two regimes. These results can be used to extract a value of the strong coupling constant ($\alpha_{\rm s}$) in addition to performing precision tests of pQCD with generators. The ENCs prove to be highly discriminative observable when compared to models, with the different generators showing a large spread in their predictions.
| Category | Experiment |
|---|---|
| Collaboration | ALEPH |
