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Journal of Physics G: Nuclear and Particle Physics - latest papers

Latest articles for Journal of Physics G: Nuclear and Particle Physics

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  • Neutrinoless double beta decay sensitivity of the XLZD rare event observatory
    The XLZD collaboration is developing a two-phase xenon time projection chamber with an active mass of 60–80 t capable of probing the remaining weakly interacting massive particle-nucleon interaction parameter space down to the so-called neutrino fog. In this work we show that, based on the performance of currently operating detectors using the same technology and a realistic reduction of radioactivity in detector materials, such an experiment will also be able to competitively search for neutrinoless double beta decay in 136Xe using a natural-abundance xenon target. XLZD can reach a 3σ discovery potential half-life of 5.7 × 1027 years (and a 90% CL exclusion of 1.3 × 1028 years) with 10 years of data taking, corresponding to a Majorana mass range of 7.3–31.3 meV (4.8–20.5 meV). XLZD will thus exclude the inverted neutrino mass ordering parameter space and will start to probe the normal ordering region for most of the nuclear matrix elements commonly considered by the community.

  • Theoretical tools for neutrino scattering: interplay between lattice QCD, EFTs, nuclear physics, phenomenology, and neutrino event generators
    Maximizing the discovery potential of increasingly precise neutrino experiments will require an improved theoretical understanding of neutrino-nucleus cross sections over a wide range of energies. Low-energy interactions are needed to reconstruct the energies of astrophysical neutrinos from supernovae bursts and search for new physics using increasingly precise measurement of coherent elastic neutrino scattering. Higher-energy interactions involve a variety of reaction mechanisms including quasi-elastic scattering, resonance production, and deep inelastic scattering that must all be included to reliably predict cross sections for energies relevant to DUNE and other accelerator neutrino experiments. Refined nuclear interaction models in these energy regimes will also be valuable for other applications, such as measurements of reactor, solar, and atmospheric neutrinos. This manuscript discusses the theoretical status, challenges, required resources, and path forward for achieving precise predictions of neutrino-nucleus scattering and emphasizes the need for a coordinated theoretical effort involved lattice QCD, nuclear effective theories, phenomenological models of the transition region, and event generators.

  • Exploring new physics in transition b → sℓ + ℓ − through different B ...
    Inspired by the discrepancies observed in the b → sℓ+ℓ− neutral current decays, we study the decay channel (ℓ = μ, τ), which is based on the same flavor changing neutral current transition at the quark level. The current study shows that this decay channel can provide a useful probe for physics beyond the standard model. We use the helicity formalism while employing the effective theory approach where we include the effects of vector and axial vector ‘new’ physics (NP) operators. In this study, we have computed the branching ratio , the helicity fraction fL, the lepton forward–backward asymmetry , and the lepton flavor universality ratio (LFU) . In addition, as a complementary check on the LFU, we also calculate the various other LFU observables, where i = AFB, fL. We assume that the NP universal coupling is present for both muons and tauons, while the non-universal coupling is only present for muons. Regarding these couplings, we employ the latest global fit to the b → sℓ+ℓ− data, which is recently computed in Algueró etal [Eur. Phys. J. C83 648 (2023)]. We give predictions of some of the mentioned observables within the SM and the various NP scenarios. We have found that not only are the considered observables sensitive to NP but are also helpful in distinguishing among the different NP scenarios. These results can be tested at the LHCb, HL-LHC, and FCC-ee, and therefore, a precise measurements of these observables not only deepens our understanding of the b → sℓ+ℓ− process but also provides a window of opportunity to possibly study various NP scenarios.

  • Physical interpretation of the 2s excitation of the nucleon
    Lattice QCD calculations of the 2s radial excitation of the nucleon place the state at an energy of approximately 1.9 GeV, raising the possibility that it is associated with the N1/2+(1880) and N1/2+(1710) resonances through mixing with two-particle meson-baryon states. The discovery of the N1/2+(1880) resonance in pion photoproduction but not in πN scattering and the small width of the N1/2+(1710) resonance suggest that a state associated with these resonances would be insensitive to the manner in which pions are permitted to dress it. To explore this possibility, we examine the spectrum of nucleon radial excitations in both 2 + 1 flavour QCD and in simulations where the coupling to meson-baryon states is significantly modified through quenching. We find the energy of the 2s radial excitation to be insensitive to this modification for quark masses close to the physical point. This invariance provides further evidence that the 2s radial excitation of the nucleon is associated with the N1/2+(1880) and N1/2+(1710) resonances.

  • Steering in neutrino oscillations with non-standard interaction
    In this study, we analyze the influence of non-standard interaction (NSI) on steering in three-flavor neutrino oscillations, with a focus on the NOνA and DUNE experimental setups. DUNE, having a longer baseline, exhibits a more pronounced deviation towards NSI in steering compared to NOνA. Within the energy range where DUNE’s maximum flux appears, the steering value for DUNE shows a 21% deviation from the standard model (SM) to NSI for normal ordering (NO), while for inverted ordering (IO), the steering value increases by approximately 15% relative to the SM. We conduct a comparative analysis of nonlocality, steering, and entanglement. Additionally, we express steering in terms of three-flavor neutrino oscillation probabilities and explore the relationship between steering inequality and concurrence.