Fri·Jun 6, 2025Friday·June 6, 2025

1. 01*

   Experimental Study of Tensor Structure Function of Deuteron

   Jiwan Poudel🇺🇸 · Alessandro Bacchetta🇮🇹 · Jian-Ping Chen🇺🇸 · Nathaly Santiesteban🇺🇸

   The deuteron is the lightest spin-1 nucleus, consisting of a weakly bound system of two spin-1/2 nucleons. One intriguing characteristic of the deuteron is the tensor polarized structure, which cannot be naively constructed combining the proton and neutron structure. The tensor structure of the deuteron provides unique insights into the quarks and gluons distributions and their dynamics within the nucleus. It can be studied experimentally through inclusive and semi-inclusive Deep Inelastic Scattering (DIS) of electrons on tensor polarized deuterons. One-dimensional (longitudinal-momentum-dependent) tensor structure functions are extracted from the inclusive DIS, whereas three-dimensional with additional transverse-momentum-dependent tensor structure functions are extracted from the semi-inclusive DIS. Experimentally, achieving high tensor polarization for such measurements has been a challenge. Significant progress has recently been made in enhancing the tensor polarization for polarized deuteron target, opening up a new window for experimental studies of the deuteron tensor structure. In this article, we discuss the tensor structure functions of the deuteron and the experimental schemes to extract these functions at Jefferson Lab, highlighting the potential measurements of the transverse-momentum-dependent tensor structure functions.

   nucl-exhep-exEPJA(2025)·14 citations
2. 02*

   Half-life determination of heavy ions in a storage ring considering feeding and depleting background processes

   R. J. Chen🇩🇪 · G. Leckenby🇨🇦 · R. S. Sidhu🇩🇪 · J. Glorius🇩🇪 · M. S. Sanjari🇩🇪 · Yu. A. Litvinov🇩🇪 · F. C. Akinci🇹🇷 · M. Bai🇩🇪 · K. Blaum🇩🇪 · F. Bosch🇩🇪 · C. Brandau🇩🇪 · T. Dickel🇩🇪 and 40 other authors

   Heavy-ion storage rings have relatively large momentum acceptance which allows for multiple ion species to circulate at the same time. This needs to be considered in radioactive decay measurements of highly charged ions, where atomic charge exchange reactions can significantly alter the intensities of parent and daughter ions. In this study, we investigate this effect using the decay curves of ion numbers in the recent ${}^{205}$Tl${}^{81+}$ bound-state beta decay experiment conducted using the Experimental Storage Ring at GSI Darmstadt. To understand the intricate dynamics of ion numbers, we present a set of differential equations that account for various atomic and nuclear reaction processes-bound-state beta decay, atomic electron recombination and capture, and electron ionization. By incorporating appropriate boundary conditions, we develop a set of differential equations that accurately simulate the decay curves of various simultaneously stored ions in the storage ring: ${}^{205}$Tl${}^{81+}$, ${}^{205}$Pb${}^{81+}$, ${}^{205}$Pb${}^{82+}$, ${}^{200}$Hg${}^{79+}$, and ${}^{200}$Hg${}^{80+}$. Through a quantitative comparison between simulations and experimental data, we provide insights into the detailed reaction mechanisms governing stored heavy ions within the storage ring. Our approach effectively models charge-changing processes, reduces the complexity of the experimental setup, and provides a simpler method for measuring the decay half-lives of highly charged ions in storage rings.

   nucl-exphysics.atom-phEPJA(2025)·1 citation
3. 03*

   The quark-gluon plasma: diagnosis with thermal hadron production from the early history until detailed characterization at high energy colliders

   Peter Braun-Munzinger🇩🇪 · Krzysztof Redlich🇵🇱 · Johanna Stachel🇩🇪

   In nuclear collisions at relativistic energies, matter is created which resembles closely the matter that filled all space until about 15 microseconds after the big bang. Here we summarize selected aspects of the research that led to the establishment of this new sub-field of physics and briefly describe its current `state of the art' with emphasis on matter creation through thermal particle production. In particular, we will focus on particle production at low transverse momentum and explain how its analysis sheds light on one of the key open questions, i.e. what is the mechanism of hadronization of colored objects such as quarks and gluons.

   ↳ nucl-thhep-exhep-phnucl-ex3 citations
4. 04*

   Toward an advanced phenomenology of $\pi N$ transition distribution amplitudes

   B. Pire🇫🇷 · K. Semenov-Tian-Shansky🇰🇷 · P. Sznajder🇵🇱 · L. Szymanowski🇵🇱

   We introduce a new approach to modeling transition distribution amplitudes (TDAs) for the processes $ep\to en{\pi }^{+}$ and $ep\to ep{\pi }^0$. The modeling is flexible, constrained by sparsely available experimental data, and satisfies theoretical requirements, including reduction to nucleon distribution amplitudes in the appropriate limit. We study the sensitivity of observable predictions to various modeling assumptions. We discuss unpolarized cross-sections, as well as the three non-vanishing polarization observables at leading twist, namely, the single transverse target spin asymmetry and the two double spin asymmetries that occur with a polarized lepton beam on either a longitudinally or transversely polarized target. The analysis is complemented by a simple Monte Carlo study to provide guidance for exploring exclusive processes in the so-called backward kinematics. Our work aims to highlight the importance of future measurements to better constrain TDAs and to support upcoming experimental proposals.

   ↳ hep-phhep-exnucl-exnucl-thPRD(2025)·3 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.