| |
Madurga, M. et al, Morales, A. I., & Nacher, E. (2026). Beta-Delayed Neutron Emission of N=84 132Cd. Phys. Rev. Lett., 136(23), 232504–7pp.
Abstract: Using the time-of-flight technique, we measured the beta-delayed neutron emission of Cd-132. From our large-scale shell model (LSSM) calculation using the (NLO)-L-3 interaction [Z. Y. Xu et al., Phys. Rev. Lett. 131, 022501 (2023)], we suggest the decay is dominated by the transformation of a neutron in the g(7/2) orbital, deep below the Fermi surface, into a proton in the g(9/2)( )orbital. We compare the beta-decay half-lives and neutron branching ratios of nuclei with Z < 50 and N >= 82 obtained with our LSSM with those of leading “global” models such as finite-range droplet model (FRDM). Our calculations match known half-lives and neutron branching ratios well and suggest that current leading models overestimate the yet-to-be-measured half-lives. Our model, backed by the Cd-132 decay data presented here, offers robust predictive power for nuclei of astrophysical interest such as r-process waiting points.
|
|
ATLAS Collaboration(Aad, G. et al), Aikot, A., Amos, K. R., Bouchhar, N., Cabrera Urban, S., Cantero, J., et al. (2026). Search for a resonance decaying into a scalar particle and a Higgs boson in the final state with two bottom quarks and two photons with 199 fb-1 of data collected at √s=13 and 13.6 TeV with the ATLAS detector. Phys. Lett. B, 877, 140425–19pp.
Abstract: A search for the resonant production of a heavy scalar X decaying into a lighter scalar S and a Higgs boson, through the process X -> S(-> b (b) over bar )H(-> gamma gamma), where the two photons are consistent with the Higgs boson decay, is performed. The search is conducted using integrated luminosities of 140 and 59 fb(-1) of proton-proton collision data at centre-of-mass energies of 13 and 13.6 TeV, respectively, recorded with the ATLAS detector at the LHC. The search is performed over the mass ranges of 170 <= m(X) <= 1000 GeV and 15 <= m(S) <= 500 GeV. No significant excess over the Standard Model background predictions is observed and limits at 95% confidence level are set on the product of cross section and branching fraction for the process X -> S(-> b (b) over bar )H(-> gamma gamma) at 13 TeV, ranging from 9 fb to 0.06 fb.
|
|
Melini, D. (2026). Top-quark physics: from Run 2 to the HL-LHC. Eur. Phys. J. Plus, 141(6), 698–5pp.
Abstract: The top quark is a fundamental particle of the standard model and plays an important role in beyond the standard model scenarios. The status of top-quark measurements by ATLAS and CMS is summarized, reporting new recent measurements of top-quark cross sections and top-quark properties. The future high-luminosity run of the Large Hadron Collider is foreseen to produce a huge dataset where top quarks can be studied in detail. The latest projections on expected results on top-quark physics in future high-luminosity runs of the Large Hadron Collider are presented, and the impact of such future measurements on testing the standard model consistency and on constraining new physics scenarios is evaluated.
|
|
ATLAS Collaboration(Aad, G. et al), Aikot, A., Amos, K. R., Bouchhar, N., Cabrera Urban, S., Cantero, J., et al. (2026). Characterization of nuclear breakup as a function of hard-scattering kinematics using dijets measured by ATLAS in p plus Pb collisions. Phys. Lett. B, 877, 140440–18pp.
Abstract: This Letter analyzes the sensitivity of event geometry estimators to the initial-state kinematics of hard scattering in proton-lead collisions. This analysis uses dijets as a proxy for the parton-parton scattering configuration, correlating it with event geometry estimators, namely the energy deposited in the Zero-Degree Calorimeter and the transverse energy recorded in the Forward Calorimeter in the Pb-going direction. The analysis uses data recorded by the ATLAS detector at the Large Hadron Collider with a nucleon-nucleon center-of-mass energy of 8.16 TeV, corresponding to an integrated luminosity of 56 nb(-1). The jets are measured within the pseudorapidity interval -2.8 < eta < 4.5, where positive eta values correspond to the direction of the proton beam. Results are presented as a function of the Bjorken-x of the parton originating from the proton, x(p). Both event geometry estimators are found to be dependent on x(p), with the energy deposited in the Zero-Degree Calorimeter about six times less sensitive to x(p) compared with the transverse energy deposited in the Forward Calorimeter.
|
|
ATLAS Collaboration(Aad, G. et al), Aikot, A., Amos, K. R., Bouchhar, N., Cabrera Urban, S., Cantero, J., et al. (2026). Search for the Higgs boson decay to a Z boson and a photon in pp collisions at √s=13 TeV and 13.6 TeV with the ATLAS detector. Phys. Lett. B, 876, 140313–21pp.
Abstract: A search for the Higgs boson decay to a.. boson and a photon in the ll gamma (l = e, mu) final state is performed using root s collisions at root s = 13.6 TeV recorded with the ATLAS detector at the Large Hadron Collider during 2022-2024, corresponding to an integrated luminosity of 165 fb(-1). The signal yield, normalised to the Standard Model prediction, is measured to be μ= 0.9(-0.6)(+0.7), compatible with the expected value of μ= 1.0 +/- 0.7. This corresponds to an observed (expected) signal significance of 1.4 (1.5) standard deviations under the background-only hypothesis. This result is combined with that of a similar search performed with 140 fb(-1) of root s = 13 TeV pp collisions to provide the best expected sensitivity to date to this rare decay, namely an observed (expected) signal strength of μ= 1.3(-0.5)(+0.6) (mu = 1.0(-0.5)(+0.6)), corresponding to an observed (expected) significance of 2.5 (1.9) standard deviations. The measurement is consistent with the Standard Model expectation.
|
|
|
