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Barbagallo, G., Cerdeira, J. L., Gomez-Fayren, C., & Ortin, T. (2025). A note on the calculation of the Komar integral in the Lorentzian Taub-NUT spacetime. Class. Quantum Gravity, 42(22), 227001–8pp.
Abstract: It has recently been shown that one can derive consistent thermodynamical expressions in the Lorentzian Taub-NUT spacetime keeping the Misner-string singularities and taking into account their contributions in the Komar integrals. We show how the same results are obtained when the Misner-string singularities are removed by using Misner's procedure because, even though the complete spacetime has no such singularities anymore, they are unavoidable in all spacelike hypersurfaces which are used in the Komar integrals. Different choices of hypersurfaces may contain different strings and lead to different physics, though.
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NEXT Collaboration(Miller, R. L. et al), Ayet, S., Cortes-Parra, C., Kellerer, F., Lopez-March, N., Martin-Albo, J., et al. (2025). Barium ion sensing with IPG K+ molecular probes. Analyst, , 10pp.
Abstract: Fluorophores covalently bound to azacrown ether ionophores can be assembled into sensitive turn-on chemosensors. The size specificity and electron-rich nature of the ionophore's binding domain contribute to both selectivity and strong turn-on fluorescence sensing by various mechanisms when properly constructed. Aza-18-crown-6 ethers are quite selective for binding to K+ and Ba2+, yet the more electron-withdrawing dicationic nature of barium imposes a larger electronic effect on turn-on fluorescent sensors. Barium chemosensors can be important for measuring soluble Ba2+ in drinking water and have gained recent attention for their potential to enhance the detection of rare events in xenon decay. Here we quantify the capability of three chemosensors, marketed for biologically useful K+ sensing, as effective probes for Ba2+ ions. We present measurements from bulk spectrofluorometry to characterize the system in aqueous solutions and demonstrate the usefulness of these species for low-background single-ion fluorescence microscopy, revealing new candidates for Ba2+ sensing.
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Cherchiglia, A., Pasquini, P., Peres, O. L. G., Rodrigues, F. F., Rossi, R. R., & Souza, E. S. (2025). Alleviating the present tension between T2K and NOνA with nonstandard neutrino interactions. Phys. Rev. D, 112(9), 093004–8pp.
Abstract: Since neutrino oscillation was observed, several experiments have been built to measure its parameters. NuMI Off-axis ve Appearance (NOvA) and Tokai-to-Kamioka (T2K) are two long-baseline experiments dedicated to measuring mainly the mixing angle 823, the charge-parity (CP) conjugation phase MCP, and the mass ordering. However, there is a tension in current data. The T2K allowed region is in conflict with the region allowed by NOvA. We propose a nonstandard charged current interaction (CC-NSI) in neutrino production to relieve this tension. The CC-NSI is computed through quantum field theory formalism, where we derive perturbative analytical formulae considering CC-NSI in the pion decay. Within this new approach, we can alleviate NOvA and T2K tension for CC-NSI complex parameters of order 10-3. We show the new phase has a degeneracy to the Dirac CP phase of the form MCP + % = 1.52c, being a possible source of violation of charge-parity symmetry.
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Ikeno, N., & Oset, E. (2025). Correlation function for the n Ds0(2317) interaction * and the issue of elastic unitarity. Phys. Rev. D, 112(9), 094019–11pp.
Abstract: We study the interaction of a neutron with the D<overline>*s0(2317) resonance and look at the amplitude below threshold and close above threshold. The study is done from the perspective that the D*s0(2317) resonance is a molecular state of DK in I = 0. To study this interaction, we use the fixed center approximation to Faddeev equations that considers the DK molecule as the cluster and the neutron as the external particle. We improve the fixed center approach to implement elastic unitarity around threshold, which is needed to obtain scattering parameters and to evaluate the nD<overline>*s0(2317) correlation function that we determine here. One interesting result of the study is the appearance of a resonant state below threshold with a binding of about 130 MeV and a width of about 80 MeV, which we suggest to look at in reactions measuring the invariant mass of pi Sigma Dbar<overline>. The ALICE collaboration has initiated studies of this type, by looking at the pf1(1285) correlation function, and we can only encourage work in this direction, which should provide much valuable information on the nature of many resonant states.
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Entem, D. R., Nieves, J., & Oller, J. A. (2025). Contact potentials in the presence of a regular finite-range interaction using dimensional regularization and the N/D method. Phys. Rev. D, 112(9), 096007–24pp.
Abstract: We solve the Lippmann-Schwinger equation (LSE) with a kernel that includes a regular finite-range potential and additional contact terms with derivatives. We employ distorted wave theory and dimensional regularization, as proposed in Nieves [Phys. Lett. B 568, 109 (2003)]. We analyze the spin singlet nucleonnucleon S-wave as case of study, with the regular one-pion exchange (OPE) potential in this partial wave and up to O(Q6) (six derivatives) contact interactions. We discuss in detail the renormalization of the LSE and show that the scattering amplitude solution of the LSE fulfills exact elastic unitarity and inherits the left-hand cut of the long-distance OPE amplitude. Furthermore, we proof that the LSE amplitude coincides with that obtained from the exact N/D calculation, with the appropriate number and typology of subtractions to reproduce the effective range parameters taken as input to renormalize the LSE amplitude. The generalization to a higher number of derivatives is straightforward.
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