In this manuscript we examine the high energy channeling radiation datasets from the CERN-NA63 experiment using ultrarelativistic synchrotron emission. To incorporate recoil, we examine the standard quasiclassical formalism as well as develop a formalism that includes the Unruh effect by utilizing a hyperbolic recoil acceleration, based on conservation of momentum, in the classical synchrotron trajectory. We also perform an asymptotic radiation timescale analysis that predicts a photon energy threshold, beyond which the Unruh effect dominates. We then compare the classical, quasiclassical, and Unruh synchrotron theories to the data. We find that above threshold, the Unruh effect saturates the spectrum of all datasets.

Germany

Morgan H. Lynch

Hyperbolic recoil and the Unruh effect at CERN-NA63

We present the implementation of the NNLO QCD corrections to double Higgs boson production at hadron colliders in G , matched to the parton shower. We include top-quark mass effects and the resummation of large logarithms of the zero-jettiness $$ {\mathcal{T}}_0 $$ , up to NNLL accuracy. This work extends our previous study, which was performed in the $\textit{m}$ → ∞ infinite top-quark mass approximation, providing a more realistic simulation framework for Higgs boson pair production. We validate our approach against NNLO predictions by M and assess the importance of mass effects comparing with our $\textit{m}$ → ∞ previous implementation.

Italy

Simone Alioli

Giulia Marinelli

Davide Napoletano

NNLO+PS double Higgs boson production with top-quark mass corrections in GENEVA

For the present work, we have used the <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mi>HYDJET</mi><mo>+</mo><mo>+</mo></mrow></math> model to explore the production of pure multi-strange hadrons in <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mi>Pb</mi><mo>+</mo><mi>Pb</mi></mrow></math> collisions at <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msqrt><msub><mi>s</mi><mrow><mi>N</mi><mi>N</mi></mrow></msub></msqrt><mo>=</mo><mn>2.76</mn></mrow></math> TeV and <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msqrt><msub><mi>s</mi><mrow><mi>N</mi><mi>N</mi></mrow></msub></msqrt><mo>=</mo><mn>5.02</mn></mrow></math> TeV collision energies, respectively. We have performed simulations to investigate transverse momentum (<math xmlns="http://www.w3.org/1998/Math/MathML"><msub><mi>p</mi><mi>T</mi></msub></math>) spectra and elliptic flow (<math xmlns="http://www.w3.org/1998/Math/MathML"><msub><mi>v</mi><mn>2</mn></msub></math>) for <math xmlns="http://www.w3.org/1998/Math/MathML"><mi>ϕ</mi></math> mesons and <math xmlns="http://www.w3.org/1998/Math/MathML"><mi mathvariant="normal">Ω</mi></math> baryons, and compared the results both with the ALICE experimental data and available model predictions for selected central classes. Furthermore, we have calculated the nuclear modification factors (<math xmlns="http://www.w3.org/1998/Math/MathML"><msub><mi>R</mi><mrow><mi>A</mi><mi>A</mi></mrow></msub></math> and <math xmlns="http://www.w3.org/1998/Math/MathML"><msub><mi>R</mi><mrow><mi>C</mi><mi>P</mi></mrow></msub></math>), which provide a perception of jet quenching phenomena. Hence, our findings enable the study of the energy and system dependence of <math xmlns="http://www.w3.org/1998/Math/MathML"><mi>ϕ</mi></math> and <math xmlns="http://www.w3.org/1998/Math/MathML"><mi mathvariant="normal">Ω</mi></math> hadrons production over a wide range of ultrarelativistic collision energies. We also present the particle ratios (<math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mi mathvariant="normal">Ω</mi><mo>/</mo><mi>ϕ</mi></mrow></math>, <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msup><mover><mi mathvariant="normal">Ω</mi><mo>¯</mo></mover><mo>+</mo></msup><mo>/</mo><msup><mi mathvariant="normal">Ω</mi><mo>−</mo></msup></mrow></math>, <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mi mathvariant="normal">Ω</mi><mo>/</mo><mi>π</mi></mrow></math>, and <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mi>ϕ</mi><mo>/</mo><mi>π</mi></mrow></math>), offering insights into the strangeness enhancement and chemical properties of the medium at both CERN Large Hadron Collider collision energies. Additionally, we also explore the predictions for the <math xmlns="http://www.w3.org/1998/Math/MathML"><mi mathvariant="normal">Ω</mi></math> baryon in <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mi>Pb</mi><mo>+</mo><mi>Pb</mi></mrow></math> collisions at <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msqrt><msub><mi>s</mi><mrow><mi>N</mi><mi>N</mi></mrow></msub></msqrt><mo>=</mo><mn>5.02</mn></mrow></math> TeV, focusing on <math xmlns="http://www.w3.org/1998/Math/MathML"><msub><mi>R</mi><mrow><mi>A</mi><mi>A</mi></mrow></msub></math>, <math xmlns="http://www.w3.org/1998/Math/MathML"><msub><mi>R</mi><mrow><mi>C</mi><mi>P</mi></mrow></msub></math>, and particle ratios within the <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mi>HYDJET</mi><mo>+</mo><mo>+</mo></mrow></math> framework, offering insights into future measurements and particle dynamics in high-energy heavy-ion collisions.

India

Gauri Devi

B.K. Singh

Production of multistrange hadrons in <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mi>Pb</mi><mo>+</mo><mi>Pb</mi></mrow></math> collisions at energies available at the CERN Large Hadron Collider using the <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mi>HYDJET</mi><mo>+</mo><mo>+</mo></mrow></math> model

In the present work, O-O collisions at <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msqrt><msub><mi>s</mi><mrow><mi>N</mi><mi>N</mi></mrow></msub></msqrt><mo>=</mo><mn>7</mn><mspace width="0.16em"></mspace><mi>TeV</mi></mrow></math> and <math xmlns="http://www.w3.org/1998/Math/MathML"><mi>p</mi></math>-O collisions at <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msqrt><msub><mi>s</mi><mrow><mi>N</mi><mi>N</mi></mrow></msub></msqrt><mo>=</mo><mn>9.9</mn><mspace width="0.16em"></mspace><mi>TeV</mi></mrow></math> are studied using the <math xmlns="http://www.w3.org/1998/Math/MathML"><mi mathvariant="normal" mathsize="small">PYTHIA8</mi></math>/Angantyr model for heavy-ion collisions. The theoretically predicted <math xmlns="http://www.w3.org/1998/Math/MathML"><mi>α</mi></math>-cluster structure of oxygen nucleus is implemented in the model to investigate the effect of the initial configuration of the oxygen nucleus on final state observables. The results obtained from the <math xmlns="http://www.w3.org/1998/Math/MathML"><mi>α</mi></math>-cluster structure are compared with those obtained from Woods-Saxon nuclear charge density distribution. The Angantyr model simulation showed that the radial distribution of the oxygen nucleus in <math xmlns="http://www.w3.org/1998/Math/MathML"><mi>α</mi></math>-cluster configuration is more compact in comparison to the Woods-Saxon distribution. The results on charged and identified particle pseudorapidity distribution are obtained in the two initial state configurations of the oxygen nucleus. The results demonstrated that the effect of initial geometrical configuration is more distinct in the noncentral collisions in comparison to the central collisions for both O-O and <math xmlns="http://www.w3.org/1998/Math/MathML"><mi>p</mi></math>-O collisions.

Deependra Sharma

Arpit Singh

Md. Samsul Islam

Basanta Nandi

Sadhana Dash

Effect of <math xmlns="http://www.w3.org/1998/Math/MathML"><mi>α</mi></math> clusters on particle production in O-O and <math xmlns="http://www.w3.org/1998/Math/MathML"><mi>p</mi></math>-O collisions at energies available at the CERN Large Hadron Collider

The effect of electron-electron interaction on positron emission in supercritical collisions of highly charged ions is studied within the monopole approximation using the time-dependent density functional theory and time-dependent Hartree–Fock–Slater methods. Positron production probabilities and energy spectra are calculated for U–U, U–Cm, and Cm–Cm collision systems, considering both bare nuclei and highly charged ions with partially filled electron shells. The results indicate that the screening of the nuclear potential by electrons as well as Pauli blocking substantially reduce positron production and suppress the characteristic signatures of spontaneous vacuum decay, previously found in collisions of bare nuclei.

Russia

N.K. Dulaev

D.A. Telnov

R.V. Popov

V.M. Shabaev

Y.S. Kozhedub

China

X. Ma

I.A. Maltsev

A.D. Mironov

I.I. Tupitsyn

Effect of electron–electron interaction on pair production in supercritical collisions of highly charged ions * The calculations within the TDDFT approach were supported by the Russian Science Foundation (22-62-00004, https://rscf.ru/project/22-62-00004/). The calculations performed using the TDHFS method were supported by the Theoretical Physics and Mathematics Advancement Foundation 'BASIS' (23-1-1-54-3). The computations were conducted based on the HybriLIT heterogeneous computing platform (LIT, JINR)

This paper presents results on multiplicity fluctuations of positively and negatively charged hadrons as well as net-electric charge fluctuations measured in central Ar+Sc interactions at beam momenta 13$\textit{A}$, 19$\textit{A}$, 30$\textit{A}$, 40$\textit{A}$, 75$\textit{A}$, and 150 $$A\,\hbox {GeV}\!/\!c$$ . The fluctuation analysis is one of the tools to search for the predicted critical point of strongly interacting matter. Results are corrected for the experimental biases and quantified using cumulant ratios. In most instances, multiplicity and net-charge distributions appear narrower than the corresponding Poisson or Skellam distributions. Cumulant ratios are compared with the model predictions, which provide a qualitative description that aligns with observations for positively and negatively charged particles. The obtained results are also compared to earlier NA61/SHINE results from inelastic $\textit{p+p}$ interactions in the same analysis acceptance.

Poland

H. Adhikary

P. Adrich

United States

K. Allison

N. Amin

E. Andronov

Norway

I.C. Arsene

M. Bajda

Y. Balkova

D. Battaglia

A. Bazgir

S. Bhosale

M. Bielewicz

France

A. Blondel

Bulgaria

M. Bogomilov

Y. Bondar

W. Bryliński

J. Brzychczyk

M. Buryakov

A. Camino

Y. Chandak

Serbia

M. Ćirković

Hungary

M. Csanád

J. Cybowska

T. Czopowicz

C. Dalmazzone

N. Davis

A. Dmitriev

P. Doetinchem

W. Dominik

J. Dumarchez

R. Engel

G. Feofilov

L. Fields

Z. Fodor

Japan

M. Friend

M. Gaździcki

K. Gollwitzer

O. Golosov

V. Golovatyuk

M. Golubeva

K. Grebieszkow

F. Guber

P. Hurh

S. Ilieva

A. Ivashkin

N. Karpushkin

M. Kiełbowicz

V. Kireyeu

R. Kolesnikov

D. Kolev

Y. Koshio

S. Kowalski

B. Kozłowski

A. Krasnoperov

W. Kucewicz

M. Kuchowicz

M. Kuich

A. László

M. Lewicki

G. Lykasov

J. Lyon

V. Lyubushkin

M. Maćkowiak-Pawłowska

B. Maksiak

A. Malakhov

A. Marcinek

A. Marino

H.J. Mathes

T. Matulewicz

V. Matveev

G. Melkumov

A. Merzlaya

Ł.. Mik

S. Morozov

Y. Nagai

T. Nakadaira

S. Nishimori

A. Olivier

V. Ozvenchuk

O. Panova

V. Paolone

I. Pidhurskyi

R. Płaneta

P. Podlaski

B. Popov

B. Pórfy

D. Prokhorova

D. Pszczel

S. Puławski

L. Ren

V. Ortiz

D. Röhrich

M. Roth

Ł.. Rozpłochowski

M. Rumyantsev

Azerbaijan

A. Rustamov

M. Rybczynski

A. Rybicki

D. Rybka

K. Sakashita

Multiplicity and net-electric charge fluctuations in central Ar+Sc interactions at 13$\textit{A}$, 19$\textit{A}$, 30$\textit{A}$, 40$\textit{A}$, 75$\textit{A}$, and 150 $$A\,\hbox {GeV}\!/\!c$$ beam momenta measured by NA61/SHINE at the CERN SPS

Using the recombination model extended to the heavy flavor scenario, we investigate the production of charmed mesons, i.e., <math xmlns="http://www.w3.org/1998/Math/MathML"><msup><mi>D</mi><mn>0</mn></msup><mo>,</mo><mo> </mo><msubsup><mi>D</mi><mi>s</mi><mo>+</mo></msubsup></math>, and <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mi>J</mi><mo>/</mo><mi>ψ</mi></mrow></math>, in <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mi>Pb</mi><mo>+</mo><mi>Pb</mi></mrow></math> collisions at <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msqrt><msub><mi>s</mi><mrow><mi>N</mi><mi>N</mi></mrow></msub></msqrt><mo>=</mo><mn>2.76</mn></mrow></math> and 5.02 TeV at the CERN Large Hadron Collider including the heavy flavor energy loss inside the hot and dense medium. Soft, semihard, and hard partons all play important roles in our model and are uniformly treated for all mesons produced. The resulting transverse momentum spectra and the second azimuthal harmonic <math xmlns="http://www.w3.org/1998/Math/MathML"><msub><mi>v</mi><mn>2</mn></msub></math> for these mesons are presented and compared with the available experimental data. The good agreement provides strong support again that the quark recombination mechanism is an effective model for hadronization in relativistic heavy-ion collisions.

Jingzong Zhang

Huanjing Gong

Hua Zheng

Wei Dai

Lilin Zhu

Spectra and azimuthal harmonic of charmed mesons in <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mi>Pb</mi><mo>+</mo><mi>Pb</mi></mrow></math> collisions at energies available at the CERN Large Hadron Collider

The energy dependence of the cross section of the ( <italic>n,p</italic>) and ( <italic>n,d</italic>) reactions on natC has been studied for the first time at the n_TOF facility at CERN, from the particle detection threshold up to 25 MeV. The measurement was performed with two telescopes made of position-sensitive silicon &#916; <italic>E</italic>- <italic>E</italic> detectors, covering the angular range from 20 &#8728; to 140 &#8728;. A detector efficiency has been determined by means of Monte Carlo simulations of the experimental setup. Various assumptions on the angular distributions and branching ratios of the excited levels of the residual 11B, 12B, 13B nuclei were considered. In particular, theoretical calculations based on the TALYS-2.0 code were used and the systematic uncertainties in the analysis results were determined from the variations in these distributions. The n_TOF data on the ( <italic>n,p</italic>) and ( <italic>n,d</italic>) reaction on carbon are characterized by a higher accuracy and wider energy range than currently available in literature. A comparison with current evaluations from different libraries reveals a rather significant disagreement with the n_TOF results, while a remarkable agreement is observed with the prediction of TALYS-2.0 for this light element.

Croatia

P. Žugec

N. Colonna

Switzerland

D. Rochman

M. Barbagallo

J. Andrzejewski

J. Perkowski

A. Ventura

D. Bosnar

A. Gawlik-Ramięga

Spain

M. Sabaté-Gilarte

Austria

M. Bacak

F. Mingrone

United Kingdom

E. Chiaveri

O. Aberle

V. Alcayne

S. Amaducci

L. Audouin

V. Babiano-Suarez

S. Bennett

E. Berthoumieux

J. Billowes

A. Brown

M. Busso

M. Caamaño

L. Caballero-Ontanaya

F. Calviño

M. Calviani

D. Cano-Ott

A. Casanovas

F. Cerutti

G. Cortés

M.A. Cortés-Giraldo

L. Cosentino

S. Cristallo

L.A. Damone

P.J. Davies

Greece

M. Diakaki

M. Dietz

C. Domingo-Pardo

R. Dressler

Q. Ducasse

Measurement of the natC( <italic>n,p</italic>) and natC( <italic>n,d</italic>) reactions from n_TOF at CERN