Tue·May 21, 2024Tuesday·May 21, 2024

1. 01*

   Experimental Study on Deuterium-Deuterium Thermonuclear Fusion with Interface Confinement

   Darong Chen🇺🇸 · Liang Jiang🇨🇳 · Shuai Chen🇨🇳 · Bao Wang · Dangguo Li🇨🇳 · Peng Liang

   Nuclear fusion is recognized as the energy of the future, and huge efforts and capitals have been put into the research of controlled nuclear fusion in the past decades. The most challenging thing for controlled nuclear fusion is to generate and keep a super high temperature. Here, a sonication system, combining with micro-scale fluid control techniques, was built to generate cavitation within a limited region. As bubbles being rapidly compressed, high temperature plasma generated interior leads to particle emissions, where a Cs2LiYCl6: Ce3+ (CLYC) scintillator was used to collect the emission events. The pulse shape discrimination methods applied on captured signals revealed that only gamma ray events were observed in sonication with normal water as excepted, while obvious separation of neutron and gamma ray events was surprisingly identified in sonication with deuterated water. This result suggested that neutrons were emitted from the sonicated deuterated water, i.e. deuterium-deuterium thermonuclear fusion was initiated. This study provides an alternative and feasible approach to achieve controllable nuclear fusion and makes great sense for future researches on the application of fusion energy.

   nucl-ex0 citations
2. 02*

   The Quark Pauli Principle and the Transmutation of Nuclear Matter

   Larry McLerran🇺🇸 · Gerald A. Miller🇺🇸

   The phase space density, ${\rho }^Q$, of quarks in nuclei is studied using realistic models of unintegrated quark distributions, known as transverse momentum densities (TMDs). If this density exceeds unity for matter at normal nuclear densities, the effects of the quark Pauli principle must play a role in nuclei, and models in which the nucleon density at low momentum is small (Quarkyonic matter) may become a starting point for an entirely new description of nuclei. We denote the nuclear density for which ${\rho }^Q=1$ to be a transmutation density, $n_T$, because quark degrees of freedom must be relevant at that density. Including the TMDs of [G. de Teramond et. al, \href{DOI:https://doi.org/10.1103/PhysRevLett.120.182001} Phys. Rev. Lett. {\bf 120}, 182002, (2018)] for the valence quarks and phenomenological TMDs for the sea quarks we find that $n_T=0.17\pm 0.04\mathrm{f}{\mathrm{m}}^{-3}$, the density of normal nuclear matter. Some of fhe implications of this finding are discussed.

   ↳ nucl-thhep-phnucl-exPRC(2024)·18 citations
3. 03*

   Random close packing of binary hard spheres favors the stability of neutron-rich atomic nuclei

   Carmine Anzivino · Vinay Vaibhav · Alessio Zaccone🇮🇹

   In spite of the success of the Bethe-Weizsäcker mass formula in its modern numerical and predictive implementations, the common-knowledge principle that it is electrostatics which, ultimately, favors neutron-rich nuclei still presents unclear aspects. For example, while it is true that the Coulomb interaction promotes the tendency towards neutron-rich nuclei, the opposite effects of Majorana exchange forces and Pauli exclusion are known to counteract this tendency. We show that a recent analytical progress in the mathematical description of random close packing of spheres with different sizes provides a missing contribution to the theoretical description of the $Z$ versus $N$ slope in the nuclides chart. In particular, the theory suggests, on geometric grounds and with a physically-reasoned assumption that the excluded-volume size of neutrons is 20\% larger than that of protons, that the most stable nuclei are those with ratio $Z/N\approx 0.75$. This new ``geometric'' random-packing contribution to the semi-empirical mass formula may be the missing aspect of nuclear structure that tilts the balance towards neutron-rich nuclei in the Segrè stability chart.

   ↳ nucl-thcond-mat.dis-nncond-mat.stat-mechhep-th+12 citations
4. 04*

   Investigation of suppression of ${\rm Y}(nS)$ in relativistic heavy-ion collisions at RHIC and LHC energies

   Junlee Kim🇨🇭 · Jaebeom Park🇺🇸 · Byungsik Hong🇰🇷 · Juhee Hong🇰🇷 · Eun-Joo Kim🇰🇷 · Yongsun Kim🇰🇷 · MinJung Kweon🇰🇷 · Su Houng Lee🇰🇷 · Sanghoon Lim🇰🇷 · Jinjoo Seo🇩🇪

   The primary purpose of studying quarkonium production in relativistic heavy-ion collisions is to understand the properties of the quark-gluon plasma. At various collision systems, measurements of quarkonium states of different binding energies, such as ${\rm Y}(nS)$, can provide comprehensive information. A model study has been performed to investigate the modification of ${\rm Y}(nS)$ production in Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}=$ 5.02 TeV and Au-Au collisions at $\sqrt{s_{\mathrm{NN}}}=$ 200 GeV. The Monte-Carlo simulation study is performed with a publicly available hydrodynamic simulation package for the quark-gluon plasma medium and a theoretical calculation of temperature-dependent thermal width of ${\rm Y}(nS)$ considering the gluo-dissociation and inelastic parton scattering for dissociation inside the medium. In addition, we perform a systematic study with different descriptions of initial collision geometry and formation time of ${\rm Y}(nS)$ to investigate their impacts on yield modification. The model calculation with a varied parameter set can describe the experimental data of ${\rm Y}(nS)$ in Pb-Pb collisions at 5.02 TeV and ${\rm Y}(2S)$ in Au-Au collisions at 200 GeV but underestimates the modification of ${\rm Y}(1S)$ at the lower collision energy. The nuclear absorption mechanism is explored to understand the discrepancy between the data and simulation.

   ↳ nucl-thnucl-exPRC(2025)·1 citation
5. 05*

   Analysis of ${}^{115}$In $\beta$ decay through the spectral moment method

   Joel Kostensalo🇫🇮 · Eligio Lisi🇮🇹 · Antonio Marrone🇮🇹 · Jouni Suhonen🇫🇮

   We analyze the ${}^{115}$In $\beta$-decay energy spectrum through the spectral moment method (SMM), previously introduced in the context of ${}^{113}$Cd $\beta$ decay. The spectral moments ${\mu }_n$ are defined as averaged $n^{\mathrm{th}}$ powers of the $\beta$ particle energy, characterizing the spectrum normalization ($n=0$) and shape ($n\ge 1$) above a given threshold. For ${}^{115}$In, we consider three independent datasets characterized by different thresholds. We also consider three nuclear model calculations with two free parameters: the ratio of axial-vector to vector couplings, $r=g_{\mathrm{A}}/g_{\mathrm{V}}$, and the small vector-like relativistic nuclear matrix element (NME), $s=s$-NME. By using the most recent of the three datasets, we show that the first few spectral moments can determine $(r,s)$ values in good agreement with those obtained by full-fledged experimental fits. We then work out the SMM results for the other datasets. We find that, although $g_{\mathrm{A}}$ quenching is generally favored, the preferred quenching factors may differ considerably depending on the chosen experimental data and nuclear models. We discuss various issues affecting both the overall normalization and the low-energy behaviour of the measured and computed spectra, and their joint effects on the experimentally quoted half-life values. Further ${}^{115}$In $\beta$-decay data at the lowest possible energy threshold appear to be crucial to clarify these issues.

   ↳ nucl-thhep-exhep-phnucl-exPRC(2024)·5 citations
6. 06*

   ${}^{164}\mathrm{Pb}$: A possible heaviest $N=Z$ doubly magic nucleus

   Tomoya Naito🇯🇵 · Masaaki Kimura🇯🇵 · Masaki Sasano🇯🇵

   We confirm by using the Skyrme Hartree-Fock-Bogoliubov calculation that ${}^{164}\mathrm{Pb}$ is a possible heaviest $N=Z$ doubly magic nucleus whose lifetime is long enough to be measured on accelerator experiments. We estimate the proton-emission and alpha-decay half-lives of ${}^{164}\mathrm{Pb}$. The estimated proton-emission half-life ranges from $0.1\mathrm{ps}$ to $10\mathrm{ns}$, while the alpha decay can be safely neglected.

   ↳ nucl-thnucl-exPRResearch(2025)·3 citations
7. 07*

   Study of hyperon-nucleon interactions at BESIII

   Jielei Zhang🇨🇳

   Hyperon-nucleon interactions are important to understand quantum chromodynamics and so-called "hyperon puzzle" of neutron star, but limited by the availability and short-lifetime of hyperon beams, the progress of relevant research is very slow. A novel method is used to study hyperon-nucleon interactions based on hyperons produced in the decays of 10 billion $J/\psi$ events collected with the BESIII detector at the BEPCII storage ring, and the target material is beam pipe. The reactions ${\Xi }^{0}n\to {\Xi }^{-}p$ and $\Lambda N\to {\Sigma }^{+}X$ have been observed and measured at BESIII. This is the first study of hyperon-nucleon interactions in electron-positron collisions and opens up a new direction for such research.

   ↳ hep-exnucl-exEPJ Web Conf.(2024)·1 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.