Thu·Jul 24, 2025Thursday·July 24, 2025

1. 01*

   Quantifying alpha clustering in the ground states of 16-O and 20-Ne

   E. Harris🇺🇸 · M. Barbui🇺🇸 · J. Bishop🇬🇧 · G. Chubarian · Sebastian Konig🇺🇸 · E. Koshchiy🇺🇸 · K.D. Launey🇺🇸 · Dean Lee🇺🇸 · Zifeng Luo🇺🇸 · Yuan-Zhuo Ma🇺🇸 · Ulf-G. Meissner🇩🇪 · C.E. Parker🇺🇸 and 9 other authors

   Understanding the role of multi-nucleon correlations in the structure of light nuclei is at the forefront of modern nuclear science. In this letter, we present a quantitative benchmark study of alpha-cluster correlations in the ground states of 16-O and 20-Ne. Experimental data provide direct evidence that the wave functions of the ground states of 16-O and 20-Ne are dominated by alpha-cluster correlations, in agreement with the predictions of sophisticated nuclear structure models. We also provide a new model-independent constraint for the alpha asymptotic normalization coefficient of the 16-O ground state and discuss the implications of these findings on the 12-C(alpha,gamma)16-O reaction, which is of critical importance for nuclear astrophysics.

   nucl-exastro-ph.SRnucl-th4 citations
2. 02*

   Dihadron fragmentation framework for near-side energy-energy correlators

   Zhong-Bo Kang🇺🇸 · Andreas Metz🇺🇸 · Daniel Pitonyak🇺🇸 · Congyue Zhang🇺🇸

   We establish an approach to analyze the free hadron and transition (nonperturbative) regions of near-side energy-energy correlators (EECs) based on dihadron fragmentation functions (DiFFs). We introduce a (nonperturbative) function we call the "EEC-DiFF" and explicitly show that expanding it for large relative transverse momentum between the two hadrons gives the $O({\alpha }_s)$ expression for the "EEC jet" function used in the quark/gluon (perturbative) region. This connection indicates that a formal theoretical matching will be able to bridge the free hadron, transition, and quark/gluon regions and allow all of them to be analyzed simultaneously. We further derive a result valid for near-side EECs in the free hadron and transition regions of $e^{+}{e}^{-}$ annihilation in terms of the EEC-DiFF. Using a simple model for the function, we perform the first fit within the dihadron framework to experimental data in this regime. We find reasonable agreement with the measurements and reproduce the salient features of near-side EECs in the free hadron and transition regions.

   ↳ hep-phhep-exnucl-exnucl-thPRL(2026)·27 citations
3. 03*

   Collinear limit of the energy-energy correlator in $e^{+}{e}^{-}$ collisions: transition from perturbative to non-perturbative regimes

   Enrico Herrmann🇺🇸 · Zhong-Bo Kang🇺🇸 · Jani Penttala🇺🇸 · Congyue Zhang🇺🇸

   We study the collinear limit of the energy-energy correlator (EEC) in $e^{+}{e}^{-}$ collisions, focusing on the transition from the perturbative QCD regime at relatively large angles to the non-perturbative region at small angles. To describe this transition, we introduce a non-perturbative jet function and perform a global analysis at NNLO+NNLL accuracy using experimental data spanning center-of-mass energies from $Q=29.0$ to $91.2$ GeV. This marks the first accurate description of the EEC across the entire near-side region ($0^{\circ }<\chi <90^{\circ }$) within a unified theoretical framework. Our analysis also provides, for the first time, a quantitative extraction of the non-perturbative contribution to the EEC quark jet function, identifying a characteristic transition scale around $2.3$ GeV - distinct from the scale observed in EEC-in-jet measurements in $pp$ collisions at the LHC, which are dominated by gluon jets. These results offer the first evidence for flavor dependence (quark vs. gluon) in the EEC and provide new insights into the interplay between perturbative and non-perturbative QCD dynamics.

   ↳ hep-phhep-exhep-thnucl-ex+121 citations

* 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.