Nuclear Theory·nucl-th

Tuesday·February 13, 2024

16 papers—9 primary·7 cross-listed

10
[Submitted on 9 Feb 2024] (cross-list from hep-lat)
Determination of the Collins-Soper kernel from Lattice QCD
Artur Avkhadiev🇺🇸 · Phiala E. Shanahan🇺🇸 · Michael L. Wagman🇺🇸 · Yong Zhao🇺🇸
This work presents a determination of the quark Collins-Soper kernel, which relates transverse-momentum-dependent parton distributions (TMDs) at different rapidity scales, using lattice quantum chromodynamics (QCD). This is the first such determination with systematic control of quark mass, operator mixing, and discretization effects. Next-to-next-to-leading logarithmic matching is used to match lattice-calculable distributions to the corresponding TMDs. The continuum-extrapolated lattice QCD results are consistent with several recent phenomenological parameterizations of the Collins-Soper kernel and are precise enough to disfavor other parameterizations.
Subjects:
High Energy Physics — Lattice (hep-lat); High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2402.06725 [pdf]
PRL(2024)·66 citations
11
[Submitted on 9 Feb 2024] (cross-list from hep-ph)
Flavor Factorization at Two-Loops
Andrew J. Larkoski🇺🇸
Recently, a factorization theorem was proposed for partonic flavor evolution as defined by the net flavor of the Winner-Take-All axis of a jet. We validate the factorization theorem through explicit calculation at two-loop order, and in the process extract all anomalous dimensions and renormalization factors for any ultraviolet-to-infrared flavor transition at this order. These results can then be used to extract the renormalized hard function for flavored jet production at next-to-next-to-leading order for any process of interest.
Comments:
24 pages + appendices, no figures; v2: minor changes, EPJC version
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2402.06735 [pdf]
EPJC(2024)·2 citations
12
[Submitted on 12 Feb 2024] (cross-list from hep-ph)
Study on the $ϕ$ -meson photoproduction off the proton target with the pentaquark-like $K^{*} Σ$ bound state $P_{s}$
Sang in Shim🇯🇵 · Yongsun Kim🇰🇷 · Seung-il Nam🇰🇷
We utilize the effective Lagrangian method within the tree-level Born approximation to explore $ϕ$ -meson photoproduction, i.e., $γ p \to ϕp$ . Our analysis encompasses contributions from various sources, including the Pomeron, $f_{1}$ -Regge, pseudoscalar particles ( $π$ , $η$ ), scalar particles ( $a_{0}$ , $f_{0}$ ), protons, and three-nucleon resonance states. In addition, we consider a possible pentaquark-like $K^{*} Σ$ -bound state $P_{s}$ . The findings indicate that, apart from the region near the threshold, contributions other than the Pomeron generally have a limited impact on the total cross section. However, at specific angles, alternative contributions become crucial, particularly at smaller values of $cos θ$ . The incorporation of $P_{s}$ and other nucleon resonances proves essential to elucidate the bump observed near $W \sim 2.15$ GeV at very forward angles and behaviors within the range of $W = (2.0 - 2.3)$ GeV. Furthermore, in the region with $W \geq 2.5$ GeV, where nucleon resonances become negligible, contributions from the t-channel mesons become pivotal. Our calculations for spin density matrix components, examined in various frames, exhibit improvement when considering all contributions. This comprehensive approach successfully reproduces the observed bump by including $P_{s}$ . We also briefly estimate the $P_{s}$ production via $ϕ$ -meson photoproduction in the future Electron-Ion Collider (EIC), resulting in the luminosity of 10 fb $^{- 1}$ per month.
Comments:
12 pages, 6 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2402.07392 [pdf]
Mod.Phys.Lett.A(2024)·4 citations
13
[Submitted on 12 Feb 2024] (cross-list from hep-th)
Pearcey integrals, Stokes lines and exact baryonic layers in the low energy limit of QCD
Sergio L. Cacciatori🇮🇹 · Fabrizio Canfora🇨🇱 · Federica Muscolino🇨🇱
The first analytic solutions representing baryonic layers living at finite baryon density within a constant magnetic field in the gauged Skyrme model are constructed. A remarkable feature of these configurations is that, if the Skyrme term is neglected, then these baryonic layers in the constant magnetic background cannot be found analytically and their energies grow very fast with the magnetic field. On the other hand, if the Skyrme term is taken into account, the field equations can be solved analytically and the corresponding solutions have a smooth limit for large magnetic fields. Thus, the Skyrme term discloses the universal character of these configurations living at finite Baryon density in a constant magnetic field. The classical gran-canonical partition function of these configurations can be expressed explicitly in terms of the Pearcey integral. This fact allows us to determine analytically the Stokes lines of the partition function and the corresponding dependence on the baryonic chemical potential as well as on the external magnetic field. In this way, we can determine various critical curves in the ( $μ_{B} - B_{e x t}$ ) plane which separates different physical behaviors. These families of inhomogeneous baryonic condensates can be also dressed with chiral conformal excitations of the solutions representing modulations of the layers themselves. Some physical consequences are analyzed.
Comments:
31 pages, 8 figures
Subjects:
High Energy Physics — Theory (hep-th); High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2402.07551 [pdf]
NPB(2024)·7 citations
14
[Submitted on 12 Feb 2024] (cross-list from hep-ph)
Nucleon electric and magnetic polarizabilities in Holographic QCD
Federico Castellani🇮🇹
We analyze the resonance contributions to the generalized Baldin sum rule, namely the sum of the generalized electric and magnetic nucleon polarizabilities $α_{E} (Q^{2})$ and $β_{M} (Q^{2})$ , within the Holographic QCD model by Witten, Sakai, and Sugimoto (WSS). In particular, we account for the contributions from the first low-lying nucleon resonances with spin 1/2 and 3/2 and both parities. After having extrapolated the WSS model parameters to fit experimental data on baryonic observables, we compare our findings with alternative predictions in literature, finding a qualitative agreement with all of them. Moreover, at least for the proton case, where data are available, our results are in qualitative accordance with resonance contributions extracted from experimental nucleon-resonance helicity amplitudes.
Comments:
11 pages, 6 figures, comments and references added, figure 6 updated
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Theory (hep-th); Nuclear Theory (nucl-th)
arXiv:
2402.07553 [pdf]
PRD(2024)·3 citations
15
[Submitted on 12 Feb 2024] (cross-list from hep-ph)
Quarkonia dissociation at finite magnetic field in the presence of momentum anisotropy
Indrani Nilima🇮🇳 · Mujeeb Hasan🇮🇳 · B. K. Singh🇮🇳 · Mohammad Yousuf Jamal🇮🇳
In this study, we investigate the potential of heavy quarkonia within a magnetized hot QGP medium having finite momentum anisotropy. The phenomenon of inverse magnetic catalysis is introduced into the system, influencing the magnetic field-modified Debye mass and thereby altering the effective quark masses. Concurrently, the impact of momentum anisotropy in the medium is considered that influence the particle distribution in the medium. The thermal decay width and dissociation temperature of quarkonium states, specifically the 1S and 2S states of charmonium and bottomonium, are computed. Our results reveal that both momentum anisotropy and the inverse magnetic catalysis effects play a significant role in modifying the thermal decay width and dissociation temperature of these heavy quarkonia states.
Comments:
14 pages, 10 figures, 2 tables
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2402.07848 [pdf]
EPJC(2024)·8 citations
16
[Submitted on 12 Feb 2024] (cross-list from hep-ph)
Jet Suppression and Azimuthal Anisotropy from RHIC to LHC
Yacine Mehtar-Tani🇺🇸 · Daniel Pablos🇪🇸 · Konrad Tywoniuk🇳🇴
Azimuthal anisotropies of high- $p_{T}$ particles produced in heavy-ion collisions are understood as an effect of a geometrical selection bias. Particles oriented in the direction in which the QCD medium formed in these collisions is shorter, suffer less energy loss, and thus, are over-represented in the final ensemble compared to those oriented in the direction in which the medium is longer. In this work we present the first semi-analytical predictions, including propagation through a realistic, hydrodynamical background, of the azimuthal anisotropies for jets, obtaining a quantitative agreement with available experimental data as function of the jet $p_{T}$ , its cone size $R$ and the collisions centrality. Jets are multi-partonic, extended objects and their energy loss is sensitive to substructure fluctuations. This is determined by the physics of color coherence that relates to the ability of the medium to resolve those partonic fluctuations. Namely, color dipoles whose angle is smaller than a critical angle, $θ_{c}$ , are not resolved by the medium and they effectively act as a coherent source of energy loss. We find that jet azimuthal anisotropies have a specially strong dependence on coherence physics due to the marked length-dependence of $θ_{c}$ . By combining our predictions for the collision systems and center of mass energies studied at RHIC and the LHC, covering a wide range of typical values of $θ_{c}$ , we show that the relative size of jet azimuthal anisotropies for jets with different cone-sizes $R$ follow a universal trend that indicates a transition from a coherent regime of jet quenching to a decoherent regime. These results suggest a way forward to reveal the role played by the physics of jet color decoherence in probing deconfined QCD matter.
Comments:
24 pages, 13 figures, published version
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2402.07869 [pdf]
PRD(2024)·39 citations

Affiliations

first authorsco-authorsvia INSPIRE

Determination of the Collins-Soper kernel from Lattice QCD

Flavor Factorization at Two-Loops

Study on the ϕ-meson photoproduction off the proton target with the pentaquark-like K∗Σ bound state Ps​

Pearcey integrals, Stokes lines and exact baryonic layers in the low energy limit of QCD

Nucleon electric and magnetic polarizabilities in Holographic QCD

Quarkonia dissociation at finite magnetic field in the presence of momentum anisotropy

Jet Suppression and Azimuthal Anisotropy from RHIC to LHC

Affiliations

Study on the $ϕ$ -meson photoproduction off the proton target with the pentaquark-like $K^{*} Σ$ bound state $P_{s}$