4–10 Apr 2022
Auditorium Maximum UJ
Europe/Warsaw timezone
Proceedings submission deadline extended to September 11, 2022

Searching for the gluon saturation scale at $x \sim 10^-5$ with the LHCb detector using direct photons

6 Apr 2022, 18:46
4m
Poster Correlations and fluctuations Poster Session 2 T07_2

Speaker

Cesar Luiz Da Silva (Los Alamos National Laboratory (US))

Description

Because of the increasing gluon density towards small-$x$, a regime where these densities reach a saturation ($Q_{\rm sat}$) is expected. The observation of this gluon saturated matter has several consequences to particle production and is a matter of an entire effective field theory, the Color Glass Condensate. The Large Hadron Collider beauty (LHCb) experiment has a privileged geometry for the search of the gluon saturation achieving an unprecedent small-$x$ coverage. The most direct measurement of gluon densities and kinematics in hadronic collisions is the inverse Compton process $(q+g\rightarrow \gamma+q)$. The LHCb experiment measured pairs of isolated photons correlated with hadrons from the quark fragmentation in pPb and Pbp collisions at 8.16 TeV probing a Bjorken-$x$ between $10^{-5}<x<10^{-1}$ with a scale down to 5 GeV$^2$, well below the expected lower-limit $Q_{\rm sat}$ in Pb nucleus. This poster will detail the measurement and discuss it in the scope of the gluon saturation and competing effects such as partonic shadowing. A discussion on future LHCb upgrades towards the extension of the gluon saturation search will also be presented.

Author

Sebastian Neubert (University of Bonn (DE))

Presentation materials