Quarkonium production in the TMD framework

Marston Copeland (LANL, Los Alamos)

Aug 25. 2026, 11:30 — 12:10

I discuss recent advances using vNRQCD and SCET to study $J/\psi$ production in the transverse momentum dependent (TMD) framework. After introducing the different energy scales and hierarchies for quarkononium production in NRQCD, I consider the TMD factorization of production cross sections for $P_{T,\psi} \sim M_\psi \ll Q$ and $P_{T,\psi} \ll M_\psi \ll Q$. In the regime where  $P_{T,\psi} \sim M_\psi \ll Q$ I show that the cross sections can still be matched onto the traditional LDMEs, which are used in the collinear factorization framework and I discuss recent results in this hierarchy. When $P_{T,\psi} \ll M_\psi \ll Q$, I show that soft gluon radiation (gluons with momentum on the order of mv $\sim$ 750 MeV) plays a critical role. In this region, the cross sections should be matched onto a new class of production operators, the TMD soft transition functions. I argue that these operators lead in the velocity powercounting and are critical for a correct description of production at low $P_T$. Finally, I present applications of this work for $J/\psi$ production at the upcoming EIC.

Further Information
Venue:
ESI Schrödinger Lecture Hall
Associated Event:
New Paradigms for Harnessing Quantum Field Theory at Colliders (Thematic Programme)
Organizer(s):
Alessandro Broggio (U of Vienna)
André H. Hoang (U of Vienna)
Bianka Meçaj (LANL, Los Alamos)
Simon Plätzer (U of Graz)
Massimiliano Procura (U of Vienna)
Rudi Rahn (U of Vienna)
Malin Sjödahl (Lund U)
Iain W. Stewart (MIT, Cambridge)