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AGATA Collaboration(Ralet, D. et al), Gadea, A., & Perez-Vidal, R. M. (2017). Toward lifetime and g factor measurements of short-lived states in the vicinity of Pb-208. Phys. Scr., 92(5), 054004–4pp.
Abstract: The multi-nucleon transfer reaction mechanism was used to produce and study nuclei in the vicinity of 208Pb. This mass region is a test case for the nuclear shell model. The mass identification of the fragments was performed with the large acceptance magnetic spectrometer VAMOS++ coupled to the AGATA gamma-tracking array. This experiment aimed to determine both lifetimes and gyromagnetic ratios of excited states with the Cologne plunger device. The analysis indicates promising results with the possibility to determine several new lifetimes in this region.
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ALEPH, D. E. L. P. H. I., L3 and OPAL Collaborations, LEP Electroweak Working Group(Schael, S. et al), Costa, M. J., Ferrer, A., Fuster, J., Garcia, C., Oyanguren, A., et al. (2013). Electroweak measurements in electron positron collisions at W-boson-pair energies at LEP. Phys. Rep., 532(4), 119–244.
Abstract: Electroweak measurements performed with data taken at the electron positron collider LEP at CERN from 1995 to 2000 are reported. The combined data set considered in this report corresponds to a total luminosity of about 3 fb(-1) collected by the four LEP experiments ALEPH, DELPHI, 13 and OPAL, at centre-of-mass energies ranging from 130 GeV to 209 GeV. Combining the published results of the four LEP experiments, the measurements include total and differential cross-sections in photon-pair, fermion-pair and four-fermion production, the latter resulting from both double-resonant WW and ZZ production as well as singly resonant production. Total and differential cross-sections are measured precisely, providing a stringent test of the Standard Model at centre-of-mass energies never explored before in electron positron collisions. Final-state interaction effects in four-fermion production, such as those arising from colour reconnection and Bose Einstein correlations between the two W decay systems arising in WW production, are searched for and upper limits on the strength of possible effects are obtained. The data are used to determine fundamental properties of the W boson and the electroweak theory. Among others, the mass and width of the W boson, m(w) and Gamma(w), the branching fraction of W decays to hadrons, B(W -> had), and the trilinear gauge-boson self-couplings g(1)(Z), K-gamma and lambda(gamma), are determined to be: m(w) = 80.376 +/- 0.033 GeV Gamma(w) = 2.195 +/- 0.083 GeV B(W -> had) = 67.41 +/- 0.27% g(1)(Z) = 0.984(-0.020)(+0.018) K-gamma – 0.982 +/- 0.042 lambda(gamma) = 0.022 +/- 0.019.
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ATLAS Collaboration(Aad, G. et al), Aikot, A., Amos, K. R., Bouchhar, N., Cabrera Urban, S., Cantero, J., et al. (2025). Climbing to the Top of the ATLAS 13 TeV data. Phys. Rep., 1116, 127–183.
Abstract: The large amount of data recorded with the ATLAS detector at the Large Hadron Collider, corresponding to 140 fb(-1) of pp collisions at a centre-of-mass energy of root s = 13 TeV, has brought our knowledge of the top quark to a higher level. The measurement of the top-antitop quark pair-production cross-section has reached a precision of 1.8% and the cross-section was measured differentially up to several TeV in multiple observables including the top-quark transverse momentum and top-quark-pair invariant mass. Single-top-quark production was studied in all production modes. Rare production processes where the top quark is associated with a vector boson, and four-top-quark production, have become accessible and cross-section measurements for several of these processes have reached uncertainties of around 10% or smaller. Innovative measurements of the top-quark mass and properties have also emerged, including the observation of quantum entanglement in the top-quark sector and tests of lepton-flavour universality using top-quark decays. Searches for flavour-changing neutral currents in the top-quark sector have been significantly improved, reaching branchingratio exclusion limits ranging from 10(-3) to 10(-5). Many of these analyses have been used to set limits on Wilson coefficients within the effective field theory framework.
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Bartram, G. et al, Morales, A. I., Orrigo, S. E. A., Rodriguez-Garcia, D., & Tain, J. L. (2026). Structure of the semi-magic 203Ir and 202Os nuclei. Phys. Lett. B, 880, 140790–5pp.
Abstract: The internal structures of the semi-magic, neutron-rich N=126 nuclei, 203Ir and 202Os, were studied. The nuclei of interest were produced using relativistic-energy projectile fragmentation of a 208Pb beam at the GSI facility in Germany. Internal isomeric decays were investigated via delayed gamma-ray spectroscopy. In 203Ir, four observed transitions were associated with parallel decay branches from an isomeric yrast 19/2+ state. An observed weak delayed gamma ray in 202Os is discussed in connection with a predicted isomeric 10+ state. Spin and parity assignments were made by comparison of the experimental data with state-of-the-art shell model calculations using three different shell-model parametrisations. It was found that the two-body interaction implemented to reproduce isomeric decays of the less exotic 204Pt and 206Hg isotones was the only interaction that describes the present experimental data. The persistence of the isomeric states, and the reproduction of the structure of the most neutron-rich N=126 nuclei ever observed, indicates that the N=126 shell closure remains robust.
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Gariazzo, S., Mena, O., & Schwetz, T. (2023). Quantifying the tension between cosmological and terrestrial constraints on neutrino masses. Phys. Dark Universe, 40, 101226–8pp.
Abstract: The sensitivity of cosmology to the total neutrino mass scale E m & nu; is approaching the minimal values required by oscillation data. We study quantitatively possible tensions between current and forecasted cosmological and terrestrial neutrino mass limits by applying suitable statistical tests such as Bayesian suspiciousness, parameter goodness-of-fit tests, or a parameter difference test. In particular, the tension will depend on whether the normal or the inverted neutrino mass ordering is assumed. We argue, that it makes sense to reject inverted ordering from the cosmology/oscillation comparison only if data are consistent with normal ordering. Our results indicate that, in order to reject inverted ordering with this argument, an accuracy on the sum of neutrino masses & sigma;(m & nu;) of better than 0.02 eV would be required from future cosmological observations.
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