Transverse-velocity scaling of femtoscopy in $\sqrt{s}=7$ TeV proton-proton collisions

TL;DR

This paper demonstrates that femtoscopic radii in high-energy proton-proton collisions scale with transverse velocity rather than transverse mass, revealing a new scaling behavior at 7 TeV energies.

Contribution

It introduces the concept of transverse velocity scaling for femtoscopic radii in proton-proton collisions and shows a semi-classical model can qualitatively reproduce this behavior.

Findings

Scaling with transverse velocity observed at 7 TeV

Semi-classical model reproduces the velocity scaling

Transverse-mass scaling fails at high energies

Abstract

Although transverse-mass scaling of femtoscopic radii is found to hold to a good approximation in heavy-ion collision experiments, it is seen to fail for high-energy proton-proton collisions. It is shown that if invariant radius parameters are plotted versus the transverse velocity instead, scaling with the transverse velocity is seen in $\sqrt{s}=7$ TeV proton-proton experiments. A simple semi-classical model is shown to qualitatively reproduce this transverse velocity scaling.