Maluf, R. V., Silva, J. E. G., Almeida, C. A. S., & Olmo, G. J. (2025). Perturbative solutions for compact objects in (2+1)-dimensional Bopp-Podolsky electrodynamics. Eur. Phys. J. C, 85(5), 594–8pp.
Abstract: We investigate the space-time geometry generated by compact objects in (2+1)-dimensional Bopp-Podolsky electrodynamics. Inspired by previous studies where the Bopp-Podolsky field acts as a source for spherically symmetric solutions, we revisit this question within the lower-dimensional (2+1) framework. Using a perturbative approach, we derive a charged BTZ-like black hole solution and compute corrections up to second order in a perturbative expansion valid far from the horizon. Our analysis suggests that the near-horizon and inner structure of the solution remain unaltered, indicating that no new non-black hole objects emerge in this regime. In particular, we do not find evidence of wormhole solutions in the (2+1)-dimensional version of this theory.
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Lei, B. F., Zhang, H., Bontoiu, C., Bonatto, A., Martin-Luna, P., Liu, B., et al. (2025). Leaky surface plasmon-based wakefield acceleration in nanostructured carbon nanotubes. Plasma Phys. Control. Fusion, 67(6), 065036–11pp.
Abstract: Metallic carbon nanotubes (CNTs) can provide ultra-dense, homogeneous plasma capable of sustaining resonant plasma waves-known as plasmons-with ultra-high field amplitudes. These waves can be efficiently driven by either high-intensity laser pulses or high-density relativistic charged particle beams. In this study, we use numerical simulations to propose that electrons and positrons can be accelerated in wakefields generated by the leaky electromagnetic field of surface plasmons. These plasmons are excited when a high-intensity optical laser pulse propagates paraxially through a cylindrical vacuum channel structured within a CNT forest. The wakefield is stably sustained by a non-evanescent longitudinal field with TV m-1-level amplitudes. This mechanism differs significantly from the plasma wakefield generation in uniform gaseous plasmas. Travelling at the speed of light in a vacuum, with phase-matched focusing fields, the wakefield acceleration is highly efficient for both electron and positron beams. We also examine two potential electron injection mechanisms: edge injection and self-injection. Both mechanisms are feasible with current laser facilities, paving the way for experimental realisation. Beyond presenting a novel method toward ultra-compact, high-energy solid-state plasma particle accelerators with ultra-high acceleration gradients, this work also expands the potential of high-energy plasmonics.
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Song, J., Yang, Z. Y., & Oset, E. (2025). Searching for the 2+partner of the Tcs0(2870) in the B- -> D- D0 K0S reaction. Phys. Rev. D, 111(9), 094004–7pp.
Abstract: We study the B- -> D- D0 K0S reaction, recently analyzed by the LHCb Collaboration, where a clear signal for the exotic Tcs0(2870) state was reported. We call attention to a small peak in the D0K0S mass distribution that could correspond to a state of the same nature as the Tcs0(2870) (D*K<overline>* nature in the molecular picture), but with JP = 2+. In order to magnify the signal for the state, we calculate the moments of the angle-mass distribution, which are linear in the resonance signal, rather than quadratic for the angle integrated mass distribution. We find spectra for the moments with a strength far bigger than that for the angle integrated mass distribution, which should encourage the evaluation of these moments from the present measurements of the reaction.
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n_TOF Collaboration(Domingo-Pardo, C. et al), Balibrea-Correa, J., Gameiro, B., de la Fuente Rosales, G., Lerendegui-Marco, J., Tarifeño-Saldivia, A., et al. (2025). Neutron capture measurements for s-process nucleosynthesis. Eur. Phys. J. A, 61(5), 105–19pp.
Abstract: This article presents a review about the main CERN nTOF contributions to the field of neutron-capture experiments of interest for s-process nucleosynthesis studies over the last 25 years, with a special focus on the measurement of radioactive isotopes. A few recent capture experiments on stable isotopes of astrophysical interest are also discussed. Results on s-process branching nuclei are appropriate to illustrate how advances in detection systems and upgrades in the facility have enabled increasingly challenging experiments and, as a consequence, have led to a better understanding and modeling of the s-process mechanism of nucleosynthesis. New endeavors combining radioactive-ion beams from ISOLDE for the production of radioisotopically pure samples for activation experiments at the new NEAR facility at nTOF are briefly discussed. On the basis of these new exciting results, also current limitations of state-of-the-art TOF and activation techniques will be depicted, thereby showing the pressing need for further upgrades and enhancements on both facilities and detection systems. A brief account of the potential technique based on inverse kinematics for direct neutron-capture measurements is also presented.
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KM3NeT Collaboration(Aiello, S. et al), Alves Garre, S., Bariego-Quintana, A., Calvo, D., Cecchini, V., Garcia Soto, A., et al. (2025). On the Potential Cosmogenic Origin of the Ultra-high-energy Event KM3-230213A. Astrophys. J. Lett., 984(2), L41–8pp.
Abstract: On 2023 February 13, the KM3NeT/ARCA telescope observed a track-like event compatible with a ultra-high-energy muon with an estimated energy of 120 PeV, produced by a neutrino with an even higher energy, making it the most energetic neutrino event ever detected. A diffuse cosmogenic component is expected to originate from the interactions of ultra-high-energy cosmic rays with ambient photon and matter fields. The flux level required by the KM3NeT/ARCA event is, however, in tension with the standard cosmogenic neutrino predictions based on the observations collected by the Pierre Auger Observatory and Telescope Array over the last decade of the ultra-high-energy cosmic rays above the ankle (hence from the local Universe, z less than or similar to 1). We show here that both observations can be reconciled by extending the integration of the equivalent cosmogenic neutrino flux up to a redshift of zmax=6 and considering either source evolution effects or the presence of a subdominant independent proton component in the ultra-high-energy cosmic-ray flux, thus placing constraints on known cosmic accelerators.
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