Pith. sign in

REVIEW 4 cited by

Accessing the speed of sound in relativistic ultracentral nucleus-nucleus collisions using the mean transverse momentum

Not yet reviewed by Pith; the record is open.

This paper has not been read by Pith yet. Machine review is queued; the pith claim, tier, and objections will appear here once it completes.

SPECIMEN: schema-true, not a live event

T0 review · schema-true

One-sentence machine reading of the paper's core claim.

pith:XXXXXXXX · record.json · timestamp

arxiv 2403.06052 v2 pith:NFWG4D5Q submitted 2024-03-10 nucl-th hep-phnucl-ex

Accessing the speed of sound in relativistic ultracentral nucleus-nucleus collisions using the mean transverse momentum

classification nucl-th hep-phnucl-ex
keywords soundspeedcollisionscorrespondenceidealmeanmomentumseveral
verification ladder T0 review T1 audit T2 compute T3 formal T4 reserved
0 comments
Share X Bluesky LinkedIn Reddit HN
read the original abstract

It has been argued that the speed of sound of the strong interaction at high temperature can be measured using the variation of the mean transverse momentum with the particle multiplicity in ultracentral heavy-ion collisions. We test this correspondence by running hydrodynamic simulations at zero impact parameter with several equations of state, at several colliding energies from 0.2 TeV to 15 TeV per nucleon pair. The correspondence is found to be precise and robust for a smooth, boost-invariant fluid and an ideal detector. We discuss the differences between this ideal setup and an actual experiment. We conclude that the extraction of the speed of sound from data is reliable, and that the main uncertainty comes from our poor knowledge of the distribution of density fluctuations at the early stages of the collision.

discussion (0)

Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.

Forward citations

Cited by 4 Pith papers

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score.

  1. Extracting the speed of sound of QCD from transverse momentum fluctuations

    hep-ph 2026-03 conditional novelty 7.0

    From ATLAS data on transverse-momentum fluctuations in ultra-central Pb+Pb collisions, the QGP speed of sound is extracted as 0.496 ± 0.008 at 221 ± 13 MeV, matching lattice QCD.

  2. High-order fluctuations of temperature in hot QCD matter

    hep-ph 2025-04 unverdicted novelty 7.0

    Introduces a new thermodynamic state function enabling computation of high-order temperature fluctuations in hot QCD matter from heavy-ion collision data, predicting strong suppression and negative skewness in the QGP phase.

  3. The size of the quark-gluon plasma in ultracentral collisions: impact of initial density fluctuations on the average transverse momentum

    nucl-th 2025-11 unverdicted novelty 5.0

    Volume variation with multiplicity in ultracentral collisions is small when total entropy scales with nuclear mass number, as shown by relating it to initial density fluctuation profiles.

  4. Revisiting the soft-hard separation in the transverse momentum spectra of $pp$ collisions

    hep-ph 2025-10 conditional novelty 4.0

    A Boltzmann fit to the low-pT ALICE spectra leaves a hard fragmentation residual with multiplicity-independent mean transverse momenta, supporting a two-component soft+hard description of pp collisions.