Scaling behaviours of the $p_{T}$ spectra for identified hadrons in $pp$ collisions

TL;DR

This paper demonstrates a universal scaling behavior in the transverse momentum spectra of identified hadrons in proton-proton collisions across different energies, explained by the color string percolation model.

Contribution

It extends the scaling analysis to identified hadrons and introduces a new method to determine the scaling parameter without assuming a specific functional form.

Findings

Scaling behavior observed for pions, kaons, and protons across energies

The scaling parameter depends on collision energy

Results support the color string percolation model

Abstract

We extend the scaling behaviour observed in the inclusive charged hadron transverse momentum ($p_{T}$) distributions to the $p_{T}$ spectra of pions, kaons and protons produced in proton-proton ($pp$) collisions with center of mass energies ($\sqrt{s}$ ) at 0.9, 2.76 and 7 TeV. This scaling behaviour arises when a linear transformation, $p_{T} \rightarrow p_{T}/K$, is applied on the pion, kaon or proton $p_{T}$ spectra. The scaling parameter $K$ depends on $\sqrt{s}$ and is determined by a new method, the quality factor method, which does not rely on the shape of the scaling function. We argue that the pions, kaons and protons originate from different distributions of clusters which are formed by strings overlapping, and the scaling behaviours of these identified particles $p_{T}$ spectra could be understood with the colour string percolation model in a quantitative way simultaneously.