| |
LHCb Collaboration(Aaij, R. et al), Jaimes Elles, S. J., Jashal, B. K., Libralon, S., Martinez-Vidal, F., Oyanguren, A., et al. (2025). Observation of Exotic J/ψφ Resonant Structure in Diffractive Processes in Proton-Proton Collisions. Phys. Rev. Lett., 134(3), 12pp.
Abstract: The first study of J/psi phi production in diffractive processes in proton-proton collisions is presented. The study is based on an LHCb dataset recorded at center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 5 fb(-1.) The data disfavor a nonresonant J/psi phi production but are consistent with a resonant model including several resonant states observed previously only in B+ -> J/psi phi K+ decays. The chi(c0)(4500) state is observed with a significance over 6 sigma and the chi(c1) (4274) is confirmed with a significance of more than 4 sigma.
|
|
ATLAS Collaboration(Aad, G. et al), Aikot, A., Amos, K. R., Bouchhar, N., Cabrera Urban, S., Cantero, J., et al. (2025). Combination of searches for singly produced vectorlike top quarks in pp collisions at √sp=13 TeV with the ATLAS detector. Phys. Rev. D, 111(1), 012012–30pp.
Abstract: A combination of searches for the single production of vectorlike top quarks (T) is presented. These analyses are based on proton-proton collisions at root sp = 13 TeV recorded in 2015-2018 with the ATLAS detector at the Large Hadron Collider, corresponding to an integrated luminosity of 139 fb(-1). The T decay modes considered in this combination are into a top quark and either a Standard Model Higgs boson or a Z boson (T -> Ht and T -> Zt). The individual searches used in the combination are differentiated by the number of leptons (e, mu) in the final state. The observed data are found to be in good agreement with the Standard Model background prediction. Interpretations are provided for a range of masses and couplings of the vectorlike top quark for benchmark models and generalized representations in terms of 95% confidence level limits. For a benchmark signal prediction of a vectorlike top quark SU(2) singlet with electroweak coupling, kappa, of 0.5, masses below 2.1 TeV are excluded, resulting in the most restrictive limits to date.
|
|
De Romeri, V., Papoulias, D. K., & Sanchez Garcia, G. (2025). Implications of the first CONUS plus measurement of coherent elastic neutrino-nucleus scattering. Phys. Rev. D, 111(7), 075025–19pp.
Abstract: The CONUS & thorn; collaboration has reported their first observation of coherent elastic neutrino-nucleus scattering (CEvNS). The experiment uses reactor electron antineutrinos and germanium detectors with recoil thresholds as low as 160 eVee. With an exposure of 327 kg x d, the measurement was made with a statistical significance of 3.76. We explore several physics implications of this observation, both within the standard model and in the context of new physics. We focus on a determination of the weak mixing angle, nonstandard and generalized neutrino interactions both with heavy and light mediators, neutrino magnetic moments, and the up-scattering of neutrinos into sterile fermions through the sterile dipole portal and new mediators. Our results highlight the role of reactor-based CEvNS experiments in probing a vast array of neutrino properties and new physics models.
|
|
Pellumaj, J. et al, & Perez-Vidal, R. M. (2025). Investigating the collectivity of intruder states along N=49 isotones. Nucl. Phys. A, 1060, 123125–6pp.
Abstract: Intruder states that originate from the promotion of neutrons across the N=50 shell gap are observed along the N=49 isotones (79Zn, 81Ge, 83Se, 85Kr), with the lowest energy in 83Se. The reduction of the N=50 shell gap towards Ni favors the lowering in the energy of these states. Moreover, since the Se nucleus (Z=34) is in the middle of the proton fp-shell (28 <= Z <= 40), it should have the maximum quadrupole correlations, lowering further the energy of these deformed configurations. This makes Se a good candidate for understanding the collectivity of the particle-hole intruder states in this region. Such information could also be used as a testing ground for theoretical models aiming to describe the region in the vicinity of 78Ni. An experiment aiming to measure the lifetime of the 540-keV 1/2+ and 1100-keV 3/2+ intruder states of 83Se was performed at LNL and is reported in this work.
|
|
Syeda, N. K. et al, & Algora, A. (2025). Investigation of the excited states of 114Sn using the GRIFFIN spectrometer at TRIUMF. Nucl. Phys. A, 1059, 123090–5pp.
Abstract: The semi-magic 110-122Sn isotopes display signs of shape coexistence in their excited 0+ states, which, in contrast to the spherical 0+ ground states, are deformed. This paper investigates the nuclear structure of 114Sn using the competing /3+ decay and electron capture of a radioactive beam of 114Sb produced at the TRIUMF-ISAC facility using the GRIFFIN spectrometer. This study will allow for an in-depth understanding of the excited 0+ states in 114Sn, by focusing on their decay patterns. In the present experiment, transitions at 856.2-keV and 1405.0-keV, which were observed in an earlier /3+ decay study but not placed in the 114Sn level scheme, have been Physics, assigned to the level scheme in connection to the 0+3 level at 2156.0-keV. Properly assigning these transitions refines the level scheme and enhances our understanding of the nuclear structure in 114Sn.
|
|
|
