Measurement of inclusive pair production cross section in collisions at TeV
Physical Review C
Published On 2023/10/23
The production cross section of inclusive J/ψ pairs in p p collisions at a center-of-mass energy s= 13 TeV is measured with ALICE. The measurement is performed for J/ψ in the rapidity interval 2.5< y< 4.0 and for transverse momentum p T> 0. The production cross section of inclusive J/ψ pairs is reported to be 10.3±2.3 (stat.)±1.3 (syst.) nb in this kinematic interval. The contribution from nonprompt J/ψ (ie, originated from beauty-hadron decays) to the inclusive sample is evaluated. The effective double-parton scattering cross section is computed, neglecting the single-parton scattering contribution.
Journal
Physical Review C
Published On
2023/10/23
Volume
108
Issue
4
Page
045203
Authors
DongHee Kim
Kyungpook National University
Position
Professor in Physics
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284
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150
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0
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0
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0
Research Interests
Particle Physics
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Sergei A. Voloshin
Wayne State University
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192
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119
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High Energy Physics
Nuclear Physics
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Alexandre Alarcon do Passo Suaide
Universidade de São Paulo
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Professor de Física
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180
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111
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física nuclear
física de partículas
tecnologia da informação
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Venelin Kozhuharov
Sofia University St. Kliment Ohridski
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79
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Particle physics
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Rene Bellwied
University of Houston
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Professor Of Physics
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174
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115
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Nuclear Physics
Relativistic Heavy Ion
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Claude Pruneau
Wayne State University
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105
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Kenta Shigaki
Hiroshima University
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Professor of Physics
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High Energy Nuclear Physics
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Marta Verweij
Universiteit Utrecht
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particle physics
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Physical Review C
resonance production in Pb-Pb collisions at TeV
The production of K*(892)±meson resonance is measured at midrapidity (| y|< 0.5) in Pb− Pb collisions at s N N= 5.02 TeV using the ALICE detector at the CERN Large Hadron Collider. The resonance is reconstructed via its hadronic decay channel K*(892)±→ K S 0 π±. The transverse momentum distributions are obtained for various centrality intervals in the p T range of 0.4− 16 GeV/c. Measurements of integrated yields, mean transverse momenta, and particle yield ratios are reported and found to be consistent with previous ALICE measurements for K*(892) 0 within uncertainties. The p T-integrated yield ratio 2 K*(892)±/(K++ K−) in central Pb− Pb collisions shows a significant suppression at a level of 9.3 σ relative to p p collisions. Thermal model calculations result in an overprediction of the particle yield ratio. Although both hadron resonance gas in partial chemical equilibrium (HRG-PCE) and music+ smash …
2024/4/3
Article DetailsShuzhe Shi
McGill University
Physical Review C
Rapidity scan approach for net-baryon cumulants with a statistical thermal model
Utilizing rapidity-dependent measurements to map the QCD phase diagram provides a complementary approach to traditional beam-energy-dependent measurements around midrapidity. The changing nature of thermodynamic properties of QCD matter along the beam axis in heavy-ion collisions at low collision energies both motivates and poses challenges for this method. In this study, we derive the analytical cumulant-generating function for subsystems within distinct rapidity windows, while accounting for global net-baryon charge conservation of the full system. Rapidity-dependent net-baryon cumulants are then calculated for a system exhibiting inhomogeneity along the beam axis, and their sensitivity to finite acceptances through changing rapidity bin widths is explored. We highlight the nontrivial behaviors exhibited by these cumulants, underscoring their importance in establishing a noncritical baseline for …
2024/3/11
Article DetailsDr. Vimlesh Kumar Ray
Gautam Buddha University
Physical Review C
Spectroscopic study of
High spin states of K 40 populated through the Al 27 (F 19, α n p) K 40 reaction at 68 MeV beam energy were studied using the Indian National Gamma Array (INGA) facility. Six new levels and fourteen new transitions were added to the existing level scheme. The spins and parities of most of the levels were assigned, modified, or confirmed from R DCO, R ADO, and linear polarization measurements. The multipole mixing ratios (δ) for most of the transitions were measured. Large-basis shell-model calculations were performed to understand the microscopic origin of the levels. Different particle restrictions in s d and p f shell orbitals were used to explain the experimental results.
2024/2/15
Article DetailsGiuseppe Mandaglio
Università degli Studi di Messina
Physical Review C
resonance production in Pb-Pb collisions at TeV
The production of K*(892)±meson resonance is measured at midrapidity (| y|< 0.5) in Pb− Pb collisions at s N N= 5.02 TeV using the ALICE detector at the CERN Large Hadron Collider. The resonance is reconstructed via its hadronic decay channel K*(892)±→ K S 0 π±. The transverse momentum distributions are obtained for various centrality intervals in the p T range of 0.4− 16 GeV/c. Measurements of integrated yields, mean transverse momenta, and particle yield ratios are reported and found to be consistent with previous ALICE measurements for K*(892) 0 within uncertainties. The p T-integrated yield ratio 2 K*(892)±/(K++ K−) in central Pb− Pb collisions shows a significant suppression at a level of 9.3 σ relative to p p collisions. Thermal model calculations result in an overprediction of the particle yield ratio. Although both hadron resonance gas in partial chemical equilibrium (HRG-PCE) and music+ smash …
2024/4/3
Article DetailsMiodrag Krmar
Univerzitet u Novom Sadu
Physical Review C
Photoactivation of the 391.69 keV isomer state of by the () reaction
Natural indium targets were exposed to high-energy bremsstrahlung radiation, from 9 MeV to 23 MeV. Using the measured γ spectra, the yield ratio of In 113 m and In 115 m was determined. It was checked to what extent the measured values of the yield ratio can be reproduced using the existing experimental data of cross sections of relevant photonuclear reactions, as well as cross sections obtained by talys calculations. The measured reaction yield ratio was used to reconstruct the energy differential cross section of In 115 (γ, 2 n) In 113 m using the unfolding procedure.
2024/3/12
Article DetailsTommaso Diotalevi
Università degli Studi di Bologna
Physical Review C
Two-particle Bose-Einstein correlations and their Lévy parameters in PbPb collisions at TeV
Two-particle Bose–Einstein momentum correlation functions are studied for charged-hadron pairs in lead-lead collisions at a center-of-mass energy per nucleon pair of s NN= 5.02 TeV. The data sample, containing 4.27× 10 9 minimum bias events corresponding to an integrated luminosity of 0.607 nb− 1, was collected by the CMS experiment in 2018. The experimental results are discussed in terms of a Lévy-type source distribution. The parameters of this distribution are extracted as functions of particle pair average transverse mass and collision centrality. These parameters include the Lévy index or shape parameter α, the Lévy scale parameter R, and the correlation strength parameter λ. The source shape, characterized by α, is found to be neither Cauchy nor Gaussian, implying the need for a full Lévy analysis. Similarly to what was previously found for systems characterized by Gaussian source radii, a …
2024/2/23
Article DetailsMasaaki Kitaguchi
Nagoya University
Physical Review C
High sensitivity of a future search for effects of -odd/-odd interactions on the 0.75 eV -wave resonance in forward transmission determined using a …
Neutron transmission experiments can offer a new type of highly sensitive search for time-reversal invariance violating (TRIV) effects in nucleon-nucleon interactions via the same enhancement mechanism observed for large parity violating (PV) effects in neutron-induced compound nuclear processes. In these compound processes, the TRIV cross section is given as the product of the PV cross section, a spin factor κ, and a ratio of TRIV and PV matrix elements. We determined κ to be 0.59±0.05 for La 139+ n using both (n, γ) spectroscopy and (n ⃗+ 139 La ⃗) transmission. This result quantifies for the first time the high sensitivity of the La 139 0.75-eV p-wave resonance in a future search for effects of P-odd/T-odd interactions in (n ⃗+ 139 La ⃗) forward transmission.
2024/4/10
Article DetailsJody K Wilson
University of New Hampshire
Physical Review C
Two-particle Bose-Einstein correlations and their Lévy parameters in PbPb collisions at TeV
Two-particle Bose–Einstein momentum correlation functions are studied for charged-hadron pairs in lead-lead collisions at a center-of-mass energy per nucleon pair of s NN= 5.02 TeV. The data sample, containing 4.27× 10 9 minimum bias events corresponding to an integrated luminosity of 0.607 nb− 1, was collected by the CMS experiment in 2018. The experimental results are discussed in terms of a Lévy-type source distribution. The parameters of this distribution are extracted as functions of particle pair average transverse mass and collision centrality. These parameters include the Lévy index or shape parameter α, the Lévy scale parameter R, and the correlation strength parameter λ. The source shape, characterized by α, is found to be neither Cauchy nor Gaussian, implying the need for a full Lévy analysis. Similarly to what was previously found for systems characterized by Gaussian source radii, a …
2024/2/23
Article DetailsJohn McDonaugh
University of Notre Dame
Physical Review C
Filtering contaminants from a -sum spectrum: Measurement of the cross section
A measurement of the Mo 94 (p, γ) Tc 95 cross section was performed. The cross section was measured in the energy range E c. m.= 1.5–4.5 MeV, spanning essentially the entirety of the Gamow window relevant to the astrophysical γ process. The γ-summing technique was used to analyze the data. At lower energies the sum peak overlapped with peaks from the reaction F 19 (p, α γ) O 16, so a new analysis method was developed to filter out the contamination from the this reaction. The measured cross section values were compared to the non-smoker database. The measured cross sections show enhanced resonancelike features at low energies, which are not predicted in the non-smoker code. The effects of this new measurement on the reaction rate were examined. It was found that there is a significant enhancement at lower temperatures in the (p, γ) reaction rate due to the enhancements found in the cross …
2024/3/20
Article DetailsMd. S. R. Laskar
Tata Institute of Fundamental Research
Physical Review C
Fusion of with at near-barrier energies
The complete and incomplete fusion cross sections for the Li 7+ Tl 205 reaction were measured at near barrier energies by the online characteristic γ-ray detection technique. The complete fusion (CF) cross sections at energies above the Coulomb barrier were found to be suppressed by∼ 26% compared to the coupled channel calculations. Reduced fusion cross sections for the present system at energies normalized to the Coulomb barrier were also found to be systematically lower than those with strongly bound projectiles forming a similar compound nucleus. The suppression observed in CF cross sections is found to be commensurate with the measured total incomplete fusion (ICF) cross sections. In the ICF cross sections, t-capture is found to be dominant than α-capture at all the measured energies. The systematic study of available CF, ICF, and total fusion data with the Li 7 projectile is performed.
2024/1/11
Article DetailsKarsten M. Heeger
Yale University
Physical Review C
Cyclotron radiation emission spectroscopy of electrons from tritium decay and 83mKr internal conversion
Project 8 has developed a novel technique, cyclotron radiation emission spectroscopy (CRES), for direct neutrino mass measurements. A CRES-based experiment on the beta spectrum of tritium has been carried out in a small-volume apparatus. We provide a detailed account of the experiment, focusing on systematic effects and analysis techniques. In a Bayesian (frequentist) analysis, we measure the tritium endpoint as 18 553− 19+ 18 (18 548− 19+ 19) eV and set upper limits of 155 (152) eV (90% CL) on the neutrino mass. No background events are observed beyond the endpoint in 82 days of running. We also demonstrate an energy resolution of 1.66±0.19 eV in a resolution-optimized magnetic trap configuration by measuring Kr 83 m 17.8-keV internal-conversion electrons. These measurements establish CRES as a low-background, high-resolution technique with the potential to advance neutrino mass …
2024/3/25
Article Details