arXiv subjects

S. O. Kara

Publications and source records attributed to S. O. Kara.

14 recordsLinked to original sources

arXiv2026

Phenomenology of Leptophilic Gauge Interactions at Future $e^+e^-$ Colliders

We present an observable-driven study of leptophilic gauge interactions mediated by a neutral vector boson $Z_\ell$ at future $e^+e^-$ colliders. Focusing on the process $e^+e^- \to μ^+μ^-$, we investigate the sensitivity of angular observables to off-shell leptophilic interactions in regimes where interference effects dominate over resonant rate enhancements. The analysis is centered on the forward-backward asymmetry, which provides a robust probe of interference-induced angular deformations and retains sensitivity well beyond the resonance region. To characterize the relative angular response independently of the overall rate modification, we additionally introduce the interference-normalized quantity $\mathcal{I}_{\rm FB}$ as a diagnostic observable. Realistic collider effects, including initial-state radiation, beamstrahlung, and finite energy resolution, are consistently incorporated. Using benchmark configurations for FCC-ee, CEPC, ILC, and CLIC, we derive projected sensitivities in the $(M_{Z_\ell}, g_\ell)$ plane. The results demonstrate the complementarity between high-luminosity circular colliders and high-energy linear colliders, reflecting the interplay between precision measurements and the energy enhancement of interference effects. Overall, the present framework provides an experimentally grounded approach for probing leptophilic gauge interactions through interference-sensitive angular observables at future lepton colliders.

hep-ph↗

arXiv2026

Quantum Encoding Framework for Leptophilic Gauge Theories

We present a systematic quantum encoding framework for leptophilic extensions of the Standard Model, tailored to quantum simulation applications on near term and future quantum devices. Focusing on anomaly free $U(1)'_{\ell}$ gauge theories, we show that the leptonic charge structure admits a natural and scalable representation on qubit registers, where gauge symmetries and anomaly cancellation conditions are enforced directly at the level of quantum states. Within this framework, gauge invariant operators are mapped to unitary quantum circuits, ensuring the preservation of gauge symmetry under quantum evolution. As a proof of principle, we construct explicit circuits that encode scattering processes mediated by a leptophilic gauge boson $Z'_{\ell}$. Our results establish a reusable bridge between beyond the Standard Model gauge theories and quantum information science, providing a concrete pathway for simulating leptophilic gauge sectors within emerging quantum computing architectures.

hep-ph↗

arXiv2026

Convergence of Heavy-Flavor PDFs at Small x and Its Impact on Future ep Colliders

We present the first quantitative demonstration of the statistical convergence of heavy-flavor parton distribution functions at small x across modern NNLO global fits. Using the latest NNPDF4.0, CT18, and MSHT20 sets, we find a maximal relative deviation of 16.8 percent at x = 1e-6 and Q = 100 GeV, corresponding to nearly a factor-of-two improvement over the approximately 30 percent spread in pre-2013 determinations. This convergence, stabilized by consistent alpha_s and scale treatments, marks a transition of the heavy-flavor sector into a statistically controlled regime of small-x QCD. We further show that this precision directly reduces PDF-driven uncertainties in heavy-quark electroproduction at future ep colliders (LHeC and FCC-eh) by about a factor of two and enhances the theoretical stability of leptophilic new-physics searches such as a neutral Z_l gauge boson. These findings establish a link between the precision frontier of QCD and the discovery potential of next-generation lepton-hadron facilities.

hep-ph↗

arXiv2025

Leptophilic Interactions in Nuclear Energy Density Functional Theory

We develop a unified theoretical framework that embeds a light leptophilic vector boson into nuclear energy density functional (EDF) theory. Starting from an underlying leptophilic gauge interaction, the mediator is integrated out in the static limit, yielding an effective current--current interaction that couples proton and lepton densities. This interaction is incorporated self-consistently into relativistic mean-field equations, defining a leptophilic extension of conventional nuclear EDFs. The resulting leptophilic EDF induces correlated modifications of proton and lepton chemical potentials, directly affecting beta equilibrium in dense matter. In uniform matter, these effects lead to percent-level changes in the proton fraction, symmetry energy, and equation of state within phenomenologically allowed parameter ranges. In finite nuclei, the modified proton mean field generates shifts of $10^{-3}$--$10^{-2}\,\mathrm{fm}$ in neutron-skin thicknesses, comparable to current experimental sensitivities. Our results demonstrate that light leptophilic interactions leave coherent and experimentally accessible imprints on both nuclear structure and dense-matter observables. The framework introduced here provides a controlled and realistic extension of nuclear EDF theory, enabling nuclear systems to serve as laboratories for probing new physics in the leptonic sector.

nucl-th↗

arXiv2025

Searching for the Leptophilic Gauge Boson Z$_{l}$ at Future $e^{+}e^{-}$ Colliders

We study the discovery prospects of the leptophilic photon Z\_l, a hypothetical gauge boson beyond the Standard Model, at future electron-positron colliders. Our analysis is based on the process e+e- -> mu+mu- and consistently includes realistic effects such as initial state radiation and beamstrahlung. Using the benchmark parameters of FCC-ee, CEPC, ILC, and CLIC, we demonstrate the complementarity of circular and linear colliders: circular machines achieve excellent sensitivity to very small couplings, down to g\_l ~ 10^{-4}, while high-energy linear colliders extend the search reach into the TeV domain.

hep-ph↗

arXiv2024

A search for leptonic photon Z_l at all three CLIC energy stages by using artificial neural networks (ANN)

In this work, the possible dynamics of the massive leptonic photon $Z_{l}$ are reconsidered via the process $e^{+}e^{-} \ rightarrow μ^{+}μ^{-}$ at Compact Linear Collider (CLIC) with updated center of mass energies ($380\ GeV,\ 1500\ GeV\ and\ 3000\ GeV$). We show that the new generation colliders as CLIC can observe massive leptophilic vector boson Z_l with mass up to the center of mass energy, provided that leptonic coupling constant is $g_{l} \geq 10^{- 3}$. In this study, we also estimated the cross-sections by artificial neural networks using the theoretical results we obtained for CLIC. According to the results obtained, it was seen that these predictions could be made through machine learning.

hep-ph↗

arXiv2017

Excited muon searches at the FCC based muon-hadron colliders

We study the excited muon production at the FCC based muon-hadron colliders. We give the excited muon decay widths and production cross section. We deal with the $μp\rightarrowμ^{\star}q\rightarrowμγq$ process and we plot the transverse momentum, rapidity and invariant mass distributions of final state particles to get the discovery cuts. By using discovery cuts, we get the mass limits for excited muons. It is shown that the discovery limits on the mass of $μ^{\star}$ are 2.2 TeV, 5.9 TeV and 7.5 TeV for $\mu63$-FCC, $\mu750$-FCC and $\mu1500$-FCC, respectively.

hep-ph↗

arXiv2012

An artificial neural network application on nuclear charge radii

The artificial neural networks (ANNs) have emerged with successful applications in nuclear physics as well as in many fields of science in recent years. In this paper, by using (ANNs), we have constructed a formula for the nuclear charge radii. Statistical modeling of nuclear charge radii by using ANNs has been seen as to be successful. Also, the charge radii, binding energies and two-neutron separation energies of Sn isotopes have been calculated by implementing of the new formula in Hartree-Fock-Bogoliubov (HFB) calculations. The results of the study shows that the new formula is useful for describing nuclear charge radii.

nucl-th↗

arXiv2012

An Approximation to the Cross Sections of Z_l Boson Production at CLIC by Using Neural Networks

In this work, the possible dynamics associated with leptophilic Z_l boson at CLIC (Compact Linear Collider) have been investigated by using artificial neural networks (ANNs). These hypotetic massive boson Z_l have been shown through the process e+e- -> M+M-. Furthermore, the invariant mass distributions for final muons have been consistently predicted by using ANN. For these highly non-linear data, we have constructed consistent empirical physical formulas (EPFs) by appropriate feed- forward ANN. These ANN-EPFs can be used to derive further physical functions which could be relevant to studying Z_l.

hep-ph↗

arXiv2012

Empirical physical formula for potential energy curves of 38-66Ti isotopes by using neural networks

Nuclear shape transition has been actively studied in the past decade. In particular, the understanding of this phenomenon from a microscopic point of view is of great importance. Because of this reason, many works have been employed to investigate shape phase transition in nuclei within the relativistic and non-relativistic mean field models by examining potential energy curves (PECs). In this paper, by using layered feed-forward neural networks (LFNNs), we have constructed consistent empirical physical formulas (EPFs) for the PECs of 38-66Ti calculated in Hartree-Fock-Bogoliubov (HFB) method with SLy4 Skyrme forces. It has been seen that the PECs obtained by neural network method are compatible with those of HFB calculations.

nucl-th↗

arXiv2012

Compensation of B-L charge of matter with relic sneutrinos

We consider massless gauge boson connected to B-L charge with and without compensation to complete the investigation of the gauging of B and L charges. Relic sneutrinos predicted by SUSY and composite models may compensate B-L charge of matter. As a consequence of the possible compensation mechanism we have shown that the available experimental data admit the range of the B-L interaction constant, 10^{-29} < α_{B-L} < 10^{-12}, in addition to α_{B-L} < 10^{-49} obtained without compensation.

hep-ph↗

arXiv2011

A Search for leptophilic Z_(l) boson at future linear colliders

We study the possible dynamics associated with leptonic charge in future linear colliders. Leptophilic massive vector boson, Z_(l), have been investigated through the process e^(+)e^(-) -> mu^(+)mu^(-). We have shown that ILC and CLIC will give opportunity to observe Z_(l) with masses up to the center of mass energy if the corresponding coupling constant g_(l) exceeds 10^(-3).

hep-ph↗

arXiv2011

Evidence for a spin-aligned neutron-proton paired phase from the level structure of $^{92}$Pd

The general phenomenon of shell structure in atomic nuclei has been understood since the pioneering work of Goeppert-Mayer, Haxel, Jensen and Suess.They realized that the experimental evidence for nuclear magic numbers could be explained by introducing a strong spin-orbit interaction in the nuclear shell model potential. However, our detailed knowledge of nuclear forces and the mechanisms governing the structure of nuclei, in particular far from stability, is still incomplete. In nuclei with equal neutron and proton numbers ($N = Z$), the unique nature of the atomic nucleus as an object composed of two distinct types of fermions can be expressed as enhanced correlations arising between neutrons and protons occupying orbitals with the same quantum numbers. Such correlations have been predicted to favor a new type of nuclear superfluidity; isoscalar neutron-proton pairing, in addition to normal isovector pairing (see Fig. 1). Despite many experimental efforts these predictions have not been confirmed. Here, we report on the first observation of excited states in $N = Z = 46$ nucleus $^{92}$Pd. Gamma rays emitted following the $^{58}$Ni($^{36}$Ar,2$n$)$^{92}$Pd fusion-evaporation reaction were identified using a combination of state-of-the-art high-resolution γ-ray, charged-particle and neutron detector systems. Our results reveal evidence for a spin-aligned, isoscalar neutron-proton coupling scheme, different from the previous prediction. We suggest that this coupling scheme replaces normal superfluidity (characterized by seniority coupling) in the ground and low-lying excited states of the heaviest N = Z nuclei. The strong isoscalar neutron- proton correlations in these $N = Z$ nuclei are predicted to have a considerable impact on their level structures, and to influence the dynamics of the stellar rapid proton capture nucleosynthesis process.

nucl-ex↗

arXiv2009

Discrimination of gamma rays due to inelastic neutron scattering in AGATA

Possibilities of discriminating neutrons and gamma rays in the AGATA gamma-ray tracking spectrometer have been investigated with the aim of reducing the background due to inelastic scattering of neutrons in the high-purity germanium crystals. This background may become a serious problem especially in experiments with neutron-rich radioactive ion beams. Simulations using the Geant4 toolkit and a tracking program based on the forward tracking algorithm were carried out by emitting neutrons and gamma rays from the center of AGATA. Three different methods were developed and tested in order to find 'fingerprints' of the neutron interaction points in the detectors. In a simulation with simultaneous emission of six neutrons with energies in the range 1-5 MeV and ten gamma rays with energies between 150 and 1450 keV, the peak-to-background ratio at a gamma-ray energy of 1.0 MeV was improved by a factor of 2.4 after neutron rejection with a reduction of the photopeak efficiency at 1.0 MeV of only a factor of 1.25.

nucl-ex↗