Wed·May 26, 2021Wednesday·May 26, 2021

1. 01*

   An experimental review of open heavy flavor and quarkonium production at RHIC

   Zebo Tang · Wangmei Zha · Yifei Zhang

   Open heavy flavor and quarkonium are unique probes of the hot-dense medium produced in heavy-ion collisions. Their production in p+p collisions also provide important test of QCD. In this paper, we review the selected results on open heavy flavor and quarkonium in p+p and heavy-ion collisions achieved at RHIC. Physics implications are also discussed.

   nucl-exNucl.Sci.Tech.(2020)·60 citations
2. 02*

   The structure of the X(3872) as explained by a Diffusion Monte Carlo calculation

   M.C. Gordillo🇪🇸 · F. De Soto🇪🇸 · J. Segovia🇪🇸

   Two decades after its unexpected discovery, the properties of the $X(3872)$ exotic resonance are still under intense scrutiny. In particular, there are doubts about its nature as an ensemble of mesons or having any other internal structure. We use a Diffusion Monte Carlo method to solve the many-body Schrödinger equation that describes this state as a $c\bar{c}n\bar{n}$ ($n=u$ or $d$ quark) system. This approach accounts for multi-particle correlations in physical observables avoiding the usual quark-clustering assumed in other theoretical techniques. The most general and accepted pairwise Coulomb$+$linear-confining$+$hyperfine spin-spin interaction, with parameters obtained by a simultaneous fit of around 100 masses of mesons and baryons, is used. The $X(3872)$ contains light quarks whose masses are given by the mechanism responsible of the dynamical breaking of chiral symmetry. The same mechanisms gives rise to Goldstone-boson exchange interactions between quarks that have been fixed in the last 10-20 years reproducing hadron, hadron-hadron and multiquark phenomenology. It appears that a meson-meson molecular configuration is preferred but, contrary to the usual assumption of $D^0{\bar{D}}^{\ast 0}$ molecule for the $X(3872)$, our formalism produces $\omega J/\psi$ and $\rho J/\psi$ clusters as the most stable ones, which could explain in a natural way all the observed features of the $X(3872)$.

   ↳ hep-phhep-exhep-latnucl-ex+1PRD(2021)·16 citations
3. 03*

   Total nuclear reaction cross-section database for radiation protection in space and heavy-ion therapy applications

   F Luoni🇩🇪 · F Horst🇩🇪 · CA Reidel · A Quarz🇩🇪 · L Bagnale🇩🇪 · L Sihver🇩🇪 · U Weber🇩🇪 · RB Norman · W de Wet · M Giraudo🇮🇹 · G Santin🇳🇱 · J Norbury🇩🇪 · M Durante🇮🇹

   Realistic nuclear reaction cross-section models are an essential ingredient of reliable heavy-ion transport codes. Such codes are used for risk evaluation of manned space exploration missions as well as for ion-beam therapy dose calculations and treatment planning. Therefore, in this study, a collection of total nuclear reaction cross-section data has been generated within a GSI-ESA-NASA collaboration. The database includes the experimentally measured total nucleus-nucleus reaction cross-sections. The Tripathi, Kox, Shen, Kox-Shen, and Hybrid-Kurotama models are systematically compared with the collected data. Details about the implementation of the models are given. Literature gaps are pointed out and considerations are made about which models fit best the existing data for the most relevant systems to radiation protection in space and heavy-ion therapy.

   ↳ nucl-thnucl-exNew J.Phys.(2021)·21 citations
4. 04*

   Coupling of pairing and triaxial shape vibrations in collective states of $\gamma$-soft nuclei

   K. Nomura🇭🇷 · D. Vretenar🇭🇷 · Z. P. Li🇨🇳 · J. Xiang

   In addition to shape oscillations, low-energy excitation spectra of deformed nuclei are also influenced by pairing vibrations. The simultaneous description of these collective modes and their coupling has been a long-standing problem in nuclear structure theory. Here we address the problem in terms of self-consistent mean-field calculations of collective deformation energy surfaces, and the framework of the interacting boson approximation. In addition to quadrupole shape vibrations and rotations, the explicit coupling to pairing vibrations is taken into account by a boson-number non-conserving Hamiltonian, specified by a choice of a universal density functional and pairing interaction. An illustrative calculation for ${}^{128}$Xe and ${}^{130}$Xe shows the importance of dynamical pairing degrees of freedom, especially for structures built on low-energy $0^{+}$ excited states, in $\gamma$-soft and triaxial nuclei.

   ↳ nucl-thnucl-exPRC(2021)·11 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.