Nuclear Theory·nucl-th

Friday·July 17, 2026

15 papers—8 primary·7 cross-listed

09
Production Effects and Final-state Interactions in $π_{1} \to 3 π$
D. Winney🇲🇽 · S. Gonzàlez-Solís🇪🇸 · M. Mikhasenko🇩🇪 · Ł. Bibrzycki🇵🇱 · C. Fernández-Ramírez🇪🇸 · V. Mathieu🇪🇸 · G. Montaña🇪🇸 · A. Pilloni🇮🇹 · L. Qiu🇺🇸 · A. Rodas🇺🇸 · A. P. Szczepaniak🇺🇸
We investigate the $π_{1} (1600)$ signal channel of $3 π$ in the $J^{P C} = 1^{-+} [π π]_{1^{--}} π P$ -wave. This channel has recently been analyzed by the COMPASS collaboration using the ``freed-isobar" technique which provides direct experimental access to the lineshape modifications of the $P$ -wave $π π$ sub-channel arising from both final state interactions and production processes such as the Deck mechanism. We motivate a unified formalism combining production effects and final state interactions using the Khuri-Treiman formalism, which is consistent with low-energy unitarity, analyticity, and crossing symmetry, seeded by an initial production amplitude. We demonstrate that the precise lineshape of the $π π$ mass spectrum can be used to determine the relative strength and complex phase of different production mechanisms contributing to the $3 π$ final state. We conduct a global fit of the $π_{1}$ freed-isobar data set, yielding a multi-dimensional parameterization of the $π_{1} \to 3 π$ decay amplitude at COMPASS as a function of both decay and production variables. We identify the contributions from short-range production and the Deck mechanism and extract the total $3 π$ invariant mass dependence which will be important for a future extraction of the $π_{1}$ pole position in the $ρ π$ channel.
↳ hep-phhep-exnucl-th0 citations
10
Exotic states with charm and/or strangeness
A. Martínez Torres🇧🇷 · Breno Agatão🇧🇷 · Pedro Brandão🇧🇷 · K. P. Khemchandani🇧🇷 · Luciano M. Abreu🇧🇷 · E. Oset🇪🇸
In this talk, I will discuss the properties of several exotic states with charm and/or strangeness. These states can be interpreted either as being generated from two- or three-hadron dynamics. In particular, I will focus on $D_{1} (2420)$ and some predictions of three-body states obtained from $n\bar
↳ hep-phnucl-th0 citations
11
A self-consistent Higgs-portal framework for dark matter--admixed neutron stars: Collider-motivated benchmarks meet multimessenger constraints
Adamu Issifu🇵🇹
We investigate dark matter (DM)-admixed neutron stars (NSs) within a self-consistent single-fluid relativistic mean-field framework by extending the Higgs-portal model with a massive $Z^{'}$ vector mediator. The resulting density-dependent repulsive interaction dynamically couples the baryonic matter (BM) and DM sectors, allowing the DM content to be characterized by the global particle fraction, $F_{χ} = N_{χ} / N_{B}$ , with the local DM density determined self-consistently as $n_{χ} = F_{χ} n_{B}$ , thereby eliminating the need for the externally prescribed DM Fermi momentum adopted in previous single-fluid models. Using the NL3 $ω ρ$ , DD2, and FSU2R EOSs, we show that increasing $F_{χ}$ systematically softens the nuclear equation of state (EOS), reduces the maximum NS mass by up to $\sim 29%$ , increases stellar compactness, and modifies the thermodynamic response of dense matter. We further derive exact analytical expressions for the adiabatic speed of sound, its density derivative, and the adiabatic index, providing a rigorous benchmark for assessing the causality and thermodynamic stability of DM-admixed EOSs. At the microscopic level, the BM--DM interaction is shown to be dominated by the repulsive $Z^{'}$ vector channel. Our framework establishes a direct connection between collider-motivated WIMP models and the multimessenger phenomenology of NSs, with potential implications for future gravitational-wave and X-ray observations.
↳ astro-ph.HEhep-phhep-thnucl-th0 citations
12
Relativistic corrections and high-energy resummation for exclusive heavy quarkonium photoproduction
Maxim Nefedov🇮🇱
The $O (v^{2})$ correction to the high-energy resummed coefficient function for the exclusive photoproduction of vector ( $1^{--}$ ) heavy quarkonia off hadrons is computed, thereby taking into account corrections of $O (v^{2} α_{s}^{n} ln^{n - 1} (x / ξ))$ . When expressed in terms of the physical vector-meson mass ( $M_{V}$ ) and the relative heavy-quark velocity ( $⟨ v^{2} ⟩$ ) using the Gremm-Kapustin relation, the computed correction turns out to be negligible at the scale $μ_{F} = M_{V}$ . However, it partially cancels the $μ_{F}$ dependence of the $O (v^{2})$ correction to the LO coefficient function in $α_{s}$ , thereby improving the robustness of the predictions.
↳ hep-phhep-exnucl-exnucl-th0 citations
13
Radiative corrections in neutral-current (anti)neutrino elastic scattering at $GeV$ energies I: Nucleon targets
Yi Chen🇨🇳 · Oleksandr Tomalak🇨🇳 · Bing-Song Zou🇨🇳
We introduce radiative corrections in neutral-current (anti)neutrino-nucleon elastic scattering at $GeV$ energies within the effective field theory framework. We factorize cross sections into soft and hard functions, clarify the (anti)neutrino flavor dependence at both amplitude and cross-section levels, and improve the quantum chromodynamics (QCD) contributions to low-energy neutral-current processes. The radiative corrections at the single-nucleon level reach a magnitude comparable to the contributions from strange quarks. We also compare our results with the experimental data from BNL E734 and MiniBooNE collaborations, finding excellent agreements with the experimental data.
↳ hep-phhep-exhep-latnucl-ex+10 citations
14
Investigation of hadronic effects on resonance productions in small collision systems using the EPOS4 model
Hyunji Lim🇰🇷 · Bong-Hwi Lim🇯🇵 · Minjung Kim🇨🇭 · Sanghoon Lim🇰🇷
Recent experimental results in high-multiplicity proton-proton (pp) collisions have suggested the possible emergence of collective behavior and medium-like effects previously considered characteristic of heavy-ion collisions. Resonance production provides a sensitive probe of such effects, as resonance yields and transverse-momentum distributions can be modified by hadronic interactions occurring between chemical and kinetic freeze-out. In this study, these effects are investigated using the EPOS4 event generator, in which hadronic final-state interactions are modeled through the UrQMD transport approach. By comparing calculations performed with and without UrQMD, the impact of hadronic interactions on resonance production is evaluated. In addition, the UrQMD contributions are separated into regeneration and rescattering, enabling a detailed investigation of both resonance production enhancement and the loss of reconstructible resonance signals. The analysis is performed for various mesonic and baryonic resonances with different lifetimes in pp collisions at LHC energies and is extended to p-O, O-O, and Pb-Pb collisions to study the system-size dependence of hadronic-phase effects. The results show that resonance production is governed by the competition between regeneration and rescattering, whose relative importance depends strongly on the resonance species, transverse momentum, and collision system. While rescattering suppresses reconstructible short-lived resonance signals, regeneration can significantly enhance the yields of several resonance species, particularly baryonic resonances. These findings demonstrate that hadronic interactions can play an important role even in small collision systems and highlight the need to measure resonances with different lifetimes and quantum numbers to constrain the dynamics and lifetime of the hadronic phase across collision systems.
↳ nucl-exnucl-th0 citations
15
Next-to-next-to-leading order QCD corrections to pion (kaon)-induced exclusive Drell-Yan process
Yu Jia🇨🇳 · Bernard Pire🇫🇷 · Qin-Tao Song🇨🇳 · Guang Tang🇨🇳 · Zhe-Yu Wang🇨🇳
The high-energy pion and kaon beams proposed for future experiments at J-PARC offer a unique opportunity to investigate exclusive Drell-Yan processes induced by pions or kaons, which correspond to inverse deeply virtual meson production with $M = π, K$ . To facilitate precise comparisons between theoretical predictions and forthcoming experimental data, we calculate the next-to-next-to-leading order (NNLO) QCD corrections to the processes $π^{-} p \to γ^{*} (\to l^{+} l^{-}) + n$ and $K^{-} p \to γ^{*} (\to l^{+} l^{-}) + Λ$ . Our calculations are performed within the generalized parton distribution (GPD) factorization framework, accurate to leading twist in the generalized Bjorken limit ( $Q^{2} ≫ ∣ t ∣, Λ_{QCD}^{2}$ ). We find that the NNLO QCD corrections are substantial and positive; therefore, their inclusion is imperative for reliable theoretical predictions in confrontation with future experiments.
↳ hep-phhep-exhep-latnucl-th0 citations

Affiliations

first authorsco-authorsvia INSPIRE

Production Effects and Final-state Interactions in π1​→3π

Exotic states with charm and/or strangeness

A self-consistent Higgs-portal framework for dark matter--admixed neutron stars: Collider-motivated benchmarks meet multimessenger constraints

Relativistic corrections and high-energy resummation for exclusive heavy quarkonium photoproduction

Radiative corrections in neutral-current (anti)neutrino elastic scattering at GeV energies I: Nucleon targets

Investigation of hadronic effects on resonance productions in small collision systems using the EPOS4 model

Next-to-next-to-leading order QCD corrections to pion (kaon)-induced exclusive Drell-Yan process

Affiliations

Production Effects and Final-state Interactions in $π_{1} \to 3 π$

Radiative corrections in neutral-current (anti)neutrino elastic scattering at $GeV$ energies I: Nucleon targets