System Size Dependence of Particle Production at the SPS

TL;DR

This paper investigates how particle production varies with system size at CERN SPS, analyzing yields and properties like transverse momentum, and discusses implications for the QCD critical point search, highlighting the core corona model's successes and limitations.

Contribution

It provides a detailed analysis of system size effects on particle yields and properties, testing the core corona model against various observables at CERN SPS.

Findings

Yields and transverse momenta depend on the number of participants, consistent with the core corona model.

Antiproton yields and net-protons at forward rapidities do not follow the model predictions.

Event-by-event fluctuations in core-corona contributions can affect fluctuation observables.

Abstract

Recent results on the system size dependence of net-baryon and hyperon production as measured at the CERN SPS are discussed. The observed Npart dependences of yields, but also of dynamical properties, such as average transverse momenta, can be described in the context of the core corona approach. Other observables, such as antiproton yields and net-protons at forward rapidities, do not follow the predictions of this model. Possible implications for a search for a critical point in the QCD phase diagram are discussed. Event-by-event fluctuations of the relative core to corona source contributions might influence fluctuation observables (e.g. multiplicity fluctuations). The magnitude of this effect is investigated.