Thu·Jun 20, 2024Thursday·June 20, 2024

1. 01*

   Direct neutrino-mass measurement based on 259 days of KATRIN data

   M. Aker🇩🇪 · D. Batzler🇩🇪 · A. Beglarian🇩🇪 · J. Behrens🇩🇪 · J. Beisenkötter🇩🇪 · M. Biassoni🇮🇹 · B. Bieringer🇩🇪 · Y. Biondi🇩🇪 · F. Block🇩🇪 · S. Bobien🇩🇪 · M. Böttcher🇩🇪 · B. Bornschein🇩🇪 and 137 other authors

   The fact that neutrinos carry a non-vanishing rest mass is evidence of physics beyond the Standard Model of elementary particles. Their absolute mass bears important relevance from particle physics to cosmology. In this work, we report on the search for the effective electron antineutrino mass with the KATRIN experiment. KATRIN performs precision spectroscopy of the tritium $\beta$-decay close to the kinematic endpoint. Based on the first five neutrino-mass measurement campaigns, we derive a best-fit value of $m_{\nu }^2=-0.14_{-0.15}^{+0.13}\mathrm{e}{\mathrm{V}}^2$, resulting in an upper limit of $m_{\nu }<0.45\mathrm{eV}$ at 90 % confidence level. With six times the statistics of previous data sets, amounting to 36 million electrons collected in 259 measurement days, a substantial reduction of the background level and improved systematic uncertainties, this result tightens KATRIN's previous bound by a factor of almost two.

   nucl-exhep-exScience(2025)·363 citations
2. 02*

   Charm and Bottom Hadrons in Hot Hadronic Matter

   Santosh K. Das🇮🇳 · Juan M. Torres-Rincon🇪🇸 · Ralf Rapp🇺🇸

   Heavy quarks, and the hadrons containing them, are excellent probes of the QCD medium formed in high-energy heavy-ion collisions, as they provide essential information on the transport properties of the medium and how quarks color-neutralize into hadrons. Large theoretical and phenomenological efforts have been dedicated thus far to assess the diffusion of charm and bottom quarks in the quark-gluon plasma and their subsequent hadronization into heavy-flavor (HF) hadrons. However, the fireball formed in heavy-ion collisions also features an extended hadronic phase, and therefore any quantitative analysis of experimental observables needs to account for the rescattering of charm and bottom hadrons. This is further reinforced by the presence of a QCD cross-over transition and the notion that the interaction strength is maximal in the vicinity of the pseudo-critical temperature. We review existing approaches for evaluating the interactions of open HF hadrons in a hadronic heat bath and the pertinent results for scattering amplitudes, spectral functions and transport coefficients. While most of the work to date has focused on $D$-mesons, we also discuss excited states as well as HF baryons and the bottom sector. Both the HF hadro-chemistry and bottom observables will play a key role in future experimental measurements. We also conduct a survey of transport calculations in heavy-ion collisions that have included effects of hadronic HF diffusion and assess its impact on various observables.

   ↳ hep-phnucl-exnucl-thPhys.Rept.(2025)·32 citations
3. 03*

   Working group 1 summary: $V_{ud}$, $V_{us}$, $V_{cd}$, $V_{cs}$ and semileptonic/leptonic $D$ decays

   Bipasha Chakraborty🇬🇧 · Alex Gilman🇬🇧 · Martin Hoferichter🇨🇭 · Michal Koval🇨🇿

   We summarize the program of working group 1 at the 12th Workshop on the CKM Unitarity Triangle, whose main subjects covered $V_{ud}$, $V_{us}$, and first-row unitarity as well as $V_{cd}$, $V_{cs}$, and (semi-)leptonic $D$ decays.

   ↳ hep-phhep-exhep-latnucl-ex+11 citation

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.