Nuclear Theory·nucl-th

Tuesday·November 9, 2021

14 papers—6 primary·8 cross-listed

07
[Submitted on 5 Nov 2021] (cross-list from hep-ph)
Transverse momentum dependent distributions in dijet and heavy hadron pair production at EIC
Rafael F. del Castillo🇪🇸 · Miguel G. Echevarria🇪🇸 · Yiannis Makris🇮🇹 · Ignazio Scimemi🇪🇸
We discuss the measurement of gluon transverse momentum distribution (TMD) in dijet and heavy hadron pair (HHP) production in semi-inclusive deep inelastic scattering. The factorization of these processes in impact parameter space shows the appearance of a specific new soft factor matrix element on top of angular a complex valued anomalous dimensions. We show in detail how these features can be treated consistently and we discuss a scale prescription for the evolution kernel of the dijet soft function. As a result we obtain phenomenological predictions for unpolarized and angular modulated cross-sections for the electron-ion collider (EIC) using current available information on unpolarized TMD.
Comments:
29 pages, 7 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2111.03703 [pdf]
JHEP(2022)·30 citations
08
[Submitted on 6 Nov 2021] (cross-list from hep-ph)
Thermal production of sexaquarks in heavy-ion collisions
D. Blaschke (1 and 2 and 3)🇵🇱 · Larissa Bravina (4)🇳🇴 · Kyrill Bugaev (5 and 6)🇺🇦 · Glennys R. Farrar (7)🇺🇸 · Boris Grinyuk (5)🇺🇦 · Oleksii Ivanytskyi (1 and 5)🇵🇱 · Sonia Kabana (8)🇨🇱 · Sergey V. Kuleshov (9 and 10)🇨🇱 · Irina K. Potashnikova (11)🇨🇱 · Violetta Sagun (12 and 5)🇺🇦 · Arkadiy Taranenko (3)🇷🇺 · Oleksandr V. Vitiuk (6)🇺🇦 and 3 other authors
We present new results on the thermal production yield of a hypothetical state made of six quarks $uu dd ss$ assuming its production in heavy-ion collisions at the CERN LHC. A state with this quark content and mass low enough to be stable against decay in timescales of the order of the age of the Universe, has been hypothesized by one of us (G.F.) and has been discussed as a possible dark matter candidate. In this work we address for the first time the thermal production rate that can be expected for this state in heavy-ion collisions at colliders. For this estimate we use a thermal model which has been shown to describe accurately the production of hadrons and nuclei in heavy-ion collisions at LHC energy. This estimate is of great relevance for sexaquark searches at colliders as well as for its consideration as a dark matter candidate and for the composition of neutron stars.
Comments:
11 pages, 2 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2111.03770 [pdf]
Int.J.Mod.Phys.A(2021)·6 citations
09
[Submitted on 6 Nov 2021] (cross-list from nucl-ex)
Perspectives in Small Systems : Heavy Quarks and HBT Radii
Debasish Das🇮🇳
Recent observations of QGP-like phenomena in small collision systems like p+p and p+A collisions have questioned our understanding of the basic paradigms of high energy heavy-ion physics. A brief discussion of these new aspects in small systems which in turn influence our understanding of hard probes like heavy quarks has been provided. Furthermore, a closer observation of the two-particle Hanbury-Brown Twiss (HBT) interferometry measurements provide new insights in our understanding of medium-like phenomena in small systems. An outlook of future goals and measurements is also made.
Comments:
Published in Nuclear Physics, Section A, 2021
Subjects:
Nuclear Experiment (nucl-ex); High Energy Physics — Experiment (hep-ex); High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2111.03926 [pdf]
NPA(2021)·4 citations
10
[Submitted on 8 Nov 2021] (cross-list from astro-ph.HE)
The effect of the energy functional on the pasta-phase properties of catalysed neutron stars
H. Dinh Thi🇫🇷 · A. F. Fantina🇫🇷 · F. Gulminelli🇫🇷
Nuclear pasta, that is an inhomogeneous distribution of nuclear matter characterised by non-spherical clustered structures, is expected to occur in a narrow spatial region at the bottom of the inner crust of neutron stars, but the width of the pasta layer is strongly model dependent. In the framework of a compressible liquid-drop model, we use Bayesian inference to analyse the constraints on the sub-saturation energy functional and surface tension imposed by both ab-initio chiral perturbation theory calculations and experimental measurements of nuclear masses. The posterior models are used to obtain general predictions for the crust-pasta and pasta-core transition with controlled uncertainties. A correlation study allows extracting the most influential parameters for the calculation of the pasta phases. The important role of high-order empirical parameters and the surface tension is underlined.
Comments:
15 pages, 11 figures. Contribution to the EPJ A topical issue "CompOSE: a repository for Neutron Star Equations of State and Transport Properties"
Subjects:
High Energy Astrophysical Phenomena (astro-ph.HE); Nuclear Theory (nucl-th)
arXiv:
2111.04374 [pdf]
EPJA(2021)·27 citations
11
[Submitted on 8 Nov 2021] (cross-list from hep-ph)
Initial-state temperature of light meson emission source from squared momentum transfer spectra in high-energy collisions
Qi Wang🇨🇳 · Fu-Hu Liu🇨🇳 · Khusniddin K. Olimov🇺🇿
The squared momentum transfer spectra of light mesons, $π^{0}$ , $π^{+}$ , $η$ , and $ρ^{0}$ , produced in high-energy virtual photon-proton ( $γ^{*} p$ ) $\to meson + nucleon$ process in electron-proton ( $e p$ ) collisions measured by the CLAS Collaboration are analyzed by the Monte Carlo calculations, where the transfer undergoes from the incident $γ^{*}$ to emitted meson or equivalently from the target proton to emitted nucleon. In the calculations, the Erlang distribution from a multi-source thermal model is used to describe the transverse momentum spectra of emitted particles. Our results show that the average transverse momentum ( $⟨ p_{T} ⟩$ ) and the initial-state temperature ( $T_{i}$ ) increase from lower squared photon virtuality ( $Q^{2}$ ) and Bjorken variable ( $x_{B}$ ) to higher one. This renders that the excitation degree of emission source, which is described by $⟨ p_{T} ⟩$ and $T_{i}$ , increases with increasing of $Q^{2}$ and $x_{B}$ .
Comments:
17 pages, 6 figures. Frontiers in Physics, accepted
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2111.04486 [pdf]
Front.in Phys.(2021)·13 citations
12
[Submitted on 8 Nov 2021] (cross-list from hep-ph)
New hadron configuration: The double-gluon hybrid state
Hua-Xing Chen🇨🇳 · Wei Chen🇨🇳 · Shi-Lin Zhu🇨🇳
This is the first study on the double-gluon hybrid, which consists of one valence quark and one valence antiquark together with two valence gluons. We concentrate on the one with the exotic quantum number $J^{P C} = 2^{+-}$ that conventional $q ˉ q$ mesons can not reach. We apply QCD sum rule method to evaluate its mass to be $2.2 6_{- 0.25}^{+ 0.20}$ GeV, and study its possible decay patterns. Especially, its three-meson decay patterns are generally not suppressed severely compared to two-meson decay patterns, so the $S$ -wave three-meson decay channels $f_{1} ω π / f_{1} ρ π$ can be useful in identifying its nature, which is of particular importance to the direct test of QCD in the low energy sector.
Comments:
5 pages, 3 figures, 1 table, revised version to be published in PRD
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); High Energy Physics — Lattice (hep-lat); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2111.04514 [pdf]
PRD(2022)·16 citations
13
[Submitted on 8 Nov 2021] (cross-list from hep-ph)
Explaining the Cabibbo Angle Anomaly
Claudio Andrea Manzari🇨🇭
The Cabibbo-Cobayashi-Maskawa (CKM) matrix parametrizes the misalignement between the up- and down-quark mass basis in the Standard Model (SM). The observation of first row CKM unitarity violation has recently emerged as a new anomaly of the SM, known as the "Cabibbo Angle Anomaly" (CAA). With current measurements, comparing the elements $V_{u d}$ and $V_{u s}$ extracted from beta and kaon decays respectively, the tension with the SM prediction amounts to $\sim$ $3 σ$ . Recently, it has been pointed out that this anomaly can also be seen as a discrepancy in the determination of the Fermi constant from muon decay vs $β$ and K decays, once CKM unitarity is assumed. In fact, possible explanations in terms on New Physics fall under two broad classes: contributions to $β$ decay and/or to $μ$ decay. In this proceedings, we discuss these solutions in terms of gauge invariant dimension 6 operators in SMEFT and simplified extensions of the Standard Model. The latter could introduce correlations with other anomalies in the SM, pointing to new and interesting directions for model building.
Comments:
7 pages, 1 figure, contribution to The European Physical Society Conference on High Energy Physics 2021 (EPS-HEP2021)
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); Nuclear Theory (nucl-th)
arXiv:
2111.04519 [pdf]
PoS(2022)·3 citations
14
[Submitted on 8 Nov 2021] (cross-list from hep-lat)
Overview of lattice calculations of the $x$ -dependence of PDFs, GPDs and TMDs
Krzysztof Cichy🇵🇱
For a long time, lattice QCD was unable to address the $x$ -dependence of partonic distributions, direct access to which is impossible in Euclidean spacetime. Recent years have brought a breakthrough for such calculations when it was realized that partonic light-cone correlations can be accessed through spatial correlations computable on the lattice. Appropriately devised observables can be factorized into physical PDFs via a perturbative procedure called matching, analogous to the standard factorization of experimental cross sections. In this short review, aimed at a broader high-energy and nuclear physics community, we discuss the recent highlights of this research program. Key concepts are outlined, followed by a case study illustrating the typical stage of current lattice extractions and by a brief review of the most recent explorations. We finalize with a number of messages for the prospects of lattice determinations of partonic structure.
Comments:
12 pages, 2 figures; invited plenary talk at the Virtual Tribute to Quark Confinement and the Hadron Spectrum 2021, August 2-6, 2021
Subjects:
High Energy Physics — Lattice (hep-lat); High Energy Physics — Experiment (hep-ex); High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2111.04552 [pdf]
EPJ Web Conf.(2022)·40 citations

Affiliations

first authorsco-authorsvia INSPIRE