PaperPanorama

Nuclear Experiment·nucl-ex

Thu·Jul 16, 2026

6 papers3 primary·3 cross-listed

  1. 01

    Nuclear Charge Radius of Be from Muonic Atom Spectroscopy Using a Microcalorimeter

    Ofir Eizenberg🇮🇱 · Shikha Rathi🇮🇱 · Andreas Abeln🇩🇪 · Sonia Bacca🇩🇪 · Gonçalo Baptista🇫🇷 · Nir Barnea🇮🇱 · Noam Burger🇮🇱 · Thomas Elias Cocolios🇧🇪 · Marie Deseyn🇧🇪 · Tim Egert🇩🇪 · Christian Enss🇩🇪 · Andreas Fleischmann🇩🇪 and 25 other authors

    The transition energy in muonic Be was measured using a metallic magnetic calorimeter, resulting in eV. The result is 30 times more precise than the previous best measurement and enables the extraction of the corresponding nuclear charge radius Befm. It is times more precise than the commonly used value based on electron scattering and differs from it by times the combined uncertainties. This measurement represents the first determination of a nuclear charge radius using muonic x-ray spectroscopy with microcalorimeters.

    nucl-exnucl-thphysics.atom-ph2 citations
  2. 02

    Evidence for sequential (nS) suppression in light ion collisions

    CMS Collaboration

    Bound states of heavy quark-antiquark pairs, known as quarkonia, have long been regarded as particularly sensitive probes of the quark-gluon plasma (QGP). Comparing quarkonium yields in collisions of heavy nuclei, such as gold or lead, with a proton-proton (pp) reference reveals a characteristic pattern of sequential suppression, in which weakly-bound excited states are more strongly suppressed than the ground states. We report the first measurements of the three lowest mass -wave vector bottomonium resonances, the ground state (1S) and the excited states (2S) and (3S), in oxygen-oxygen collisions at a center-of-mass energy per nucleon pair of = 5.36 TeV. Measurements of the yields of the (1S) and (2S) resonances in neon-neon collisions, at the same , are also presented. The (2S)/(1S) ratio is found to be significantly below the measured pp reference value, and the (3S)/(1S) ratio shows an even larger reduction. The significance of the relative (3S) to (2S) suppression exceeds three standard deviations. These results provide evidence for the sequential suppression of (nS) states in light ion collisions, similar to observations made in lead-lead and gold-gold collisions, generally attributed to the presence of a QGP medium.

    nucl-exhep-exnucl-th3 citations
  3. 03

    High-precision measurement of the kaonic hydrogen 1s level shift and width with SIDDHARTA-2

    M. Bazzi🇮🇹 · F. Clozza🇮🇹 · C. Guaraldo🇮🇹 · M. A. Iliescu🇮🇹 · A. Scordo🇮🇹 · F. Sgaramella🇮🇹 · D. Sirghi🇮🇹 · F. Sirghi🇮🇹 · J. Zmeskal🇮🇹 · L. Abbene🇮🇹 · C. Amsler🇦🇹 · F. Artibani🇮🇹 and 28 other authors

    Kaonic atoms provide a unique experimental probe of strong interaction in the low-energy regime. In particular, the strong-interaction-induced shift () and width () of kaonic hydrogen directly constrain the low-energy antikaon-nucleon () interaction at threshold and the theoretical description of the (1405) resonance. We report a new high-precision measurement of kaonic hydrogen X-ray transitions performed by the SIDDHARTA-2 experiment at the DANE collider (INFN-LNF), based on an integrated luminosity of 237 pb. The extracted values, eV and eV, represent the most precise determination to date, improving the precision by approximately a factor-of-two with respect to the previous SIDDHARTA measurement. These results significantly tighten the experimental constraints on theoretical description of the low-energy interaction.

    nucl-exphysics.atom-ph0 citations
  4. 04

    Profile-Likelihood and Baseline-Sensitivity Diagnostics for Digitized Radiation-Sensor Decay Datasets

    Victor V. Golovko

    Accurate interpretation of radiation-sensor decay data is important for environmental monitoring, site remediation, radiation metrology, detector quality assurance, and nuclear data evaluation. When the original gamma-spectrometry records are unavailable, a published decay plot may be the only source that can be reanalyzed independently. This study presents a reproducible reduced-data workflow for testing half-life estimates from a digitized 198-Au decay dataset. A weighted exponential fit to the digitized data points reproduces the published room-temperature half-life, indicating that the main decay scale is retained in the figure-level dataset. The analysis then tests how the fitted result changes under plausible figure-level effects, including baseline-like offsets, time-axis reconstruction, finite-window leverage, and ratio-based robustness checks using pairwise summaries and Steiner's most frequent value statistics. The no-offset fit is locally well constrained, but small constant offsets can shift the fitted half-life because the normalization, decay constant, and residual baseline are partly degenerate over the limited time window. Toy Monte Carlo diagnostics show that some estimator shifts are expected for finite-window exponential data. This study does not revise recommended nuclear data or replace the original experiment. Instead, it shows how published radiation-sensor decay data can be tested for reproducibility, identifiability, and sensitivity to analysis choices when only reduced or figure-level information is available.

    physics.data-annucl-exSensors(2026)·0 citations
  5. 05

    Weak charged current induced electron and positron scattering off proton at JLab and MAMI energies

    A. Fatima🇮🇳 · M. Sajjad Athar🇮🇳 · S. K. Singh🇮🇳

    The development of next-generation, high-luminosity, and high-precision charged lepton beam facilities at JLab and MAMI has opened, in recent years, a new frontier in the exploration of weak interaction processes induced by electrons and positrons in the neutral current sector, which can also be used to study weak interaction processes induced by charged currents. In particular, these processes in the intermediate energy regime, spanning from a few hundred MeV to a few GeV, play a crucial role in understanding electroweak dynamics, nucleon structure, and hadronic response functions. This review presents a comprehensive theoretical study of weak charged-current interactions of electrons and positrons with free protons, encompassing quasielastic scattering in both the strangeness conserving and strangeness changing channels, together with inelastic production of the (1232), (1440), (1535) resonances, and mesons, and associated production of strange particles. We analyse differential and total cross sections, polarization observables of the final baryons, and spin asymmetries of the proton target, demonstrating their sensitivity to the underlying weak interaction dynamics and to possible second class currents, thereby enabling stringent tests of G- and T- invariance. The explored kinematic region also offers a unique and independent opportunity to constrain the axial vector sector of the weak interaction, and it provides a discussion of alternative ways to determine the axial dipole mass in the quasielastic scattering region, a fundamental parameter that is in debate for nearly two decades. It also focuses on the study of the axial-vector form factors associated with the excitation of the resonance in a manner that is free from the uncertainties inherent in their determination from studies of (anti)neutrino-induced weak processes.

    hep-phhep-exnucl-exnucl-th1 citation
  6. 06

    Characterisation of a Thick Pixelated Silicon Detector for Electron Spectroscopy of Neutron Beta Decay

    Manuel Lebert🇩🇪 · Lilli Löbell🇩🇪 · Igor Konorov🇩🇪 · Bastian Märkisch🇩🇪

    Silicon detectors are commonly used for spectroscopy of low-energy particles. For electrons in the 1 MeV range, a rather large thickness of 2mm is required to entirely stop the electrons and commercial options are scarce. With the instrument PERC at the FRM II, we aim to measure beta spectra from polarised and unpolarised neutrons in order to determine the axial-vector coupling constant, the element of the Cabibbo-Kobayashi-Maskawa quark-mixing matrix, and to search for hypothetical scalar and tensor contributions. We present the characterisation of a commercially available, pixelated detector to assess its suitability to measure the entire electron energy spectrum of free neutron beta decay.

    physics.ins-detnucl-ex0 citations

Affiliations

first authorsco-authorsvia INSPIRE