Scaling of transverse energies and multiplicities with atomic number and energy in ultrarelativistic nuclear collisions

K.J. Eskola; K. Kajantie; K. Tuominen; P.V. Ruuskanen

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Scaling of transverse energies and multiplicities with atomic number and energy in ultrarelativistic nuclear collisions

K.J. Eskola, K. Kajantie, P.V. Ruuskanen, K. Tuominen

High Energy Physics - Phenomenology · Submitted 21 Sep 1999

abstract compiled · 2026-09-23 · no language-model review

The authors' main claim The main emphasis of the study is at LHC and RHIC energies but it is observed that even at SPS energies this approach leads to results which are not unreasonable: what is usually described as a completely soft nonperturbative process can also be described in terms of gluons and quarks.

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arXiv IDhep-ph/9909456 (version 1)

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CitationK.J. Eskola, K. Kajantie, K. Tuominen, P.V. Ruuskanen. "Scaling of transverse energies and multiplicities with atomic number and energy in ultrarelativistic nuclear collisions." arXiv:hep-ph/9909456 (1999). https://pith.science/paper/V4WY5AWZ

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What the abstract itself states, as probabilities: claims first 0.03 · states limitation 0.54 · human participants 0.01 · controlled comparison 0.03 · randomized assignment 0.01 · states quantitative result 0.06 · compares with prior results 0.23 · mentions code or data availability 0.02.

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We compute how the initial energy density and produced gluon, quark and antiquark numbers scale with atomic number and beam energy in ultrarelativistic heavy ion collisions. The computation is based on the argument that the effect of all momentum scales can be estimated by performing the computation at one transverse momentum scale, the saturation momentum. The initial numbers are converted to final ones by assuming kinetic thermalisation and adiabatic expansion. The main emphasis of the study is at LHC and RHIC energies but it is observed that even at SPS energies this approach leads to results which are not unreasonable: what is usually described as a completely soft nonperturbative process can also be described in terms of gluons and quarks. The key element is the use of the saturation scale.

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What the classifier reports for each sentence. The number is the probability it gave the label.
#	sentence	role	the authors' own work	states the main conclusion	strength
s0	We compute how the initial energy density and produced gluon, quark and antiquark numbers scale with atomic number and beam energy in ultrarelativistic heavy ion collisions.	contribution 1.00	0.95	0.13	asserted 0.99
s1	The computation is based on the argument that the effect of all momentum scales can be estimated by performing the computation at one transverse momentum scale, the saturation momentum.	method 1.00	0.68	0.08	asserted 0.96
s2	The initial numbers are converted to final ones by assuming kinetic thermalisation and adiabatic expansion.	method 1.00	0.75	0.05	asserted 0.95
s3	The main emphasis of the study is at LHC and RHIC energies but it is observed that even at SPS energies this approach leads to results which are not unreasonable: what is usually described as a completely soft nonperturbative process can also be described in terms of gluons and quarks.	result 0.62	0.85	0.26	asserted 0.72
s4	The key element is the use of the saturation scale.	contribution 0.48	0.51	0.21	asserted 1.00

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Original abstract

We compute how the initial energy density and produced gluon, quark and antiquark numbers scale with atomic number and beam energy in ultrarelativistic heavy ion collisions. The computation is based on the argument that the effect of all momentum scales can be estimated by performing the computation at one transverse momentum scale, the saturation momentum. The initial numbers are converted to final ones by assuming kinetic thermalisation and adiabatic expansion. The main emphasis of the study is at LHC and RHIC energies but it is observed that even at SPS energies this approach leads to results which are not unreasonable: what is usually described as a completely soft nonperturbative process can also be described in terms of gluons and quarks. The key element is the use of the saturation scale.

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References

Forward citations

Cited by 13 Pith papers

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How the literature uses it

30 arXiv papers cite this in 50 sentences

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Papers citing it · 33 sentences without a confident label

Uses its method or tool 7 papers

We obtain the primary partonic transverse energy production and the formation time in central AA collisions from the EKRT model [ref] .

Elliptic flow from pQCD + saturation + hydro model · Introduction · 0.80
The saturation scale is determined as $p_0=p_sat$ from a saturation condition [ref] $N_AA(p_0, √(s))·π/p_0^2 = c ·πR_A^2,$ where $N_AA(p_0, √(s))$ is the average number of partons produced at $|y|≤0.5$ and $p_T≥p_0$.

Hadron multiplicities, pT-spectra and net-baryon number in central Pb+Pb collisions at the LHC · Introduction · 0.92
Our reference baseline is central collisions, for which we obtain the initial densities from the EKRT minijet (final state) saturation model [ref] .

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A similar scaling is also noticed in the EKRT initial condition model based on pQCD particle production and saturation physics [ref] .

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Works into this direction include the developments of the IP-Sat+MUSIC (Impact parameter dependent saturation + MUScl for Ion Collisions) model [ref] , the EKRT (Eskola-Kajantie-Ruuskanen-Tuominen) model [ref] , the EPOS (Energy conservation + Parallel scattering + factOrization + Saturation) model [ref] , the AMPT (A Multi-Phase Transport) model [ref] , and the Dynamical Core-Corona Initialization model [ref] with initial state generated by Pythia Angantyr [ref] , as well as initial state models such as in Refs. [ref] .

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So far initial state models based on saturation physics, such as IP-Glasma [ref] , EKRT [ref] or MC-KLN [ref] have primarily been designed to describe the initial state around mid-rapidity in 2+1D hydro simulations.

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