A comparative study of hadron-hadron and heavy-ion collision using the $q$-Weibull distribution function

TL;DR

This study probes whether Quark-Gluon Plasma (QGP)-like signatures appear in high-multiplicity $pp$ collisions by analyzing charged-hadron $p_T$ spectra across $pp$, $pPb$, and $PbPb$ systems with the $q$-Weibull distribution. The approach fits spectra over wide $p_T$ ranges using the Tsallis-extended $q$-Weibull form, extracting parameters $q$, $k$, and $λ$ to quantify non-equilibrium effects, hard scattering contributions, and collective expansion. Key results show that $k$ increases with the $p_T$ range, and that $q$ trends differ between small and large systems: heavy-ion data display a centrality-dependent decrease at low $p_T$ with a reversal at high $p_T$, while high-multiplicity $pp$ data exhibit lower $q$ values even at high $p_T$, suggesting distinct production mechanisms and the influence of multi-partonic interactions (MPI). The findings highlight different thermodynamic trajectories in small versus large collision systems and call for further theoretical work to interpret $q$ in terms of equilibration and QGP signatures.

Abstract

Recent results on multiplicity dependent transverse momentum spectra data in different high multiplicity $pp$ collision have opened a window to search for QGP like medium in hadron-hadron collision. In this work we have performed a comparative study of charged hadron spectra in $pp$, $pPb$ and $PbPb$ collision using the $q$ parameter obtained from the $q$-Weibull distribution function. We observed a disparity in the trend of $q$ parameter in high $p_T$ range.

Figures (7)

• Figure 1: Transverse momentum spectra of charged hadron produced in $pp$ collision at 5.02 TeV Acharya:2019mzb fitted with $q$-Weibull distribution function for different $p_T$ range.
• Figure 2: Transverse momentum spectra of charged hadron produced in $pp$ collision at 7 TeV Acharya:2018orn fitted with $q$-Weibull distribution function for different $p_T$ range.
• Figure 3: Transverse momentum spectra of charged hadron produced in $pp$ collision at 13 TeV Acharya:2019mzb fitted with $q$-Weibull distribution function for different $p_T$ range.
• Figure 4: Transverse momentum spectra of charged hadron produced in $PbPb$ collision at 2.76 TeV Abelev:2012hxa fitted with $q$-Weibull distribution function for different $p_T$ range.
• Figure 5: Variation of $k$ parameter with varying $p_T$ range obtained by fitting most central/highest multiplicity data of charged hadron spectra produced $pp$Acharya:2018ornAcharya:2019mzb, $pPb$Adam:2016dau and $PbPb$Abelev:2012hxa collision at different energies.