The volume and surface components of the nuclear symmetry energy (NSE) and their ratio are calculated within the coherent density fluctuation model (CDFM). The estimations use the results of the model for the NSE in finite nuclei based on the Brueckner energy-density functional for nuclear matter. In addition, we present results for the NSE and its volume and surface contributions obtained by using the Skyrme energy-density functional. The CDFM weight function is obtained using the proton and neutron densities from the self-consistent HF+BCS method with Skyrme interactions. We present and discuss the values of the volume and surface contributions to the NSE and their ratio obtained for the Ni, Sn, and Pb isotopic chains studying their isotopic sensitivity. The results are compared with estimations of other approaches which have used available experimental data on binding energies, neutron-skin thicknesses, excitation energies to isobaric analog states (IAS) and also with results of other theoretical methods.
We derive the values of nuclear symmetry energy, its components, as well as pressure in finite nuclei at saturation density from their corresponding values in nuclear matter obtained in non-relativistic Brueckner-Hartree-Fock calculations with the realistic Bonn B and Bonn CD potentials using the coherent density fluctuation model in the framework of a self-consistent Skyrme-Hartree-Fock plus BCS method. We focus on three isotopic chains of spherical nuclei (Ni, Sn, and Pb) and compare our results with those obtained with an effective Brueckner density-dependent potential. The role of the thre…
Anomalous Behavior of Giant Monopole Resonance Energy with Nuclear Matter Incompressibility in the framework of Relativistic Mean Field Formalism and Coherent Density Fluctuation Model
Institute of Physics, Sachivalaya Marg(萨奇瓦拉亚Marg物理研究所)
Phase-space excluded-volume approach for light clusters in nuclear medium
Istituto Nazionale di Fisica Nucleare (INFN), Sezione di Catania(意大利国家核物理研究所卡塔尼亚分部);Sino-French Institute of Nuclear Engineering and Technology, Sun Yat-Sen University(中山大学中法核工程与技术学院);INFN, Laboratori Nazionali del Sud(意大利国家核物理研究所南方实验室)
The multiplicity fluctuations are studied in the van der Waals excluded volume hadron-resonance gas model. The calculations are done in the grand canonical ensemble within the Boltzmann statistics approximation. The scaled variances for positive, negative and all charged hadrons are calculated along the chemical freeze-out line of nucleus-nucleus collisions at different collision energies. The multiplicity fluctuations are found to be suppressed in the van der Waals gas. The numerical calculations are presented for two values of hard-core hadron radius, $r=0.3$ fm and 0.5 fm, as well as for th…
Nuclear matter superfluidity in an effective hadronic field model with excluded volume corrections
研究了有限温度下对称核物质1 S 0超流相的性质。它是描述在一个协变强子场模型,σ-ω型,增加了密度依赖的相关模拟效应,由于有限的核子扩展。该模型求解自洽的Hartree-Bogoliubov方法,假设瞬时相互作用的超流相。并与几种强子场模型的结果作了比较。我们描述的超流间隙的主要特点是在定性协议与一些研究使用微观势,虽然进一步的细化可以提高其性能。
Realistic nuclear structure calculations are presented for the event rates due to coherent elastic neutrino-nucleus scattering (CE$ν$NS), assuming neutrinos from pion-decay at-rest, from nuclear reactors and from Earth's interior. We focus on the currently interesting Germanium isotopes, $^{70,73,76}$Ge, which constitute detector materials of the recently planned CE$ν$NS experiments. We study in addition the potential use of $^{64,70}$Zn and $^{28}$Si isotopes as promising CE$ν$NS detectors. From nuclear physics perspectives, recently, calculations have been carried out within the framework of…
Long Time Energy Oscillation Between Electron Shell and Nucleus in $^{229}$Th Ions and Coherent Electron Bridge for Nuclear Quantum Battery
P. N. Lebedev Physical Institute of the Russian Academy of Sciences(俄罗斯科学院列别杰夫物理研究所);National Research Nuclear University MEPhI(国立核研究大学莫斯科工程物理学院);Institute of Nuclear and Radiation Physics, Russian Federal Nuclear Center-VNIIEF(俄罗斯联邦核中心-VNIIEF核与辐射物理研究所);Nuclear Safety Institute of the Russian Academy of Sciences(俄罗斯科学院核安全研究所)
A new alternative approach to calculate the ratio of the surface to volume components of the nuclear symmetry energy is proposed in the framework of the coherent density fluctuation model (CDFM). A new expression (scheme II) for the ratio is derived consistently within the model. This expression appears in a form more direct and physically motivated than the expression (scheme I) that was used in our previous works within the CDFM and avoids preliminary assumptions and mathematical ambiguities in scheme I. The calculations are based on the Skyrme and Brueckner energy-density functionals for nu…
Evidence for Color Fluctuations in Hadrons from Coherent Nuclear Diffraction}
利用基于量子色动力学的弹丸尺寸涨落处理方法计算了相干强子-核过程的非弹性衍射截面$σ_{diff}$。我们发现,平均尺寸附近的波动给出了主要的贡献与$ \le few \%$贡献的小尺寸配置的截面。$σ_{diff}$的计算值与有限的可用数据一致。强调了在高能费米实验室固定靶实验中对大范围射弹进行相干衍射研究的重要性。这些显着的颜色起伏的相对论性重离子碰撞的影响进行了讨论。
In the transition from nuclear matter to finite nuclei, complex finite-size effects which characterise open systems arise, in relation with either the nuclear surface or the bulk. In addition, the non-equilibrium character of the process, typical of violent heavy-ion collisions (from Fermi energy to the intermediate-energy domain) adds up as well. The resulting dynamics is the combination of surface and volume unstable modes which trigger large-amplitude fluctuations. A rich variety of fragmentation patterns may emerge, ranging from collimated streams of nuclear clusters to the split of a stre…
Population of the 8 eV $^{229m}$Th isomer via the second nuclear excited state at 29.19 keV by means of coherent x-ray pulses is investigated theoretically. We focus on two nuclear coherent population transfer schemes using partially overlapping x-ray pulses known from quantum optics: stimulated Raman adiabatic passage (STIRAP), and successive $π$ pulses. Numerical results are presented for three possible experimental setups. Our results identify the Gamma Factory as the most promising scenario, where two ultraviolet pulses combined with relativistically accelerated ions deliver the required i…
While the phenomenon of gluon nuclear shadowing at small $x$ has been getting confirmation in QCD analyses of various LHC measurements involving heavy nuclei, it has not been possible so far to establish experimentally the number of target nucleons responsible for nuclear shadowing in a given process. To address this issue, we study coherent $J / ψ$ electroproduction on $^4$He and $^3$He in the kinematics of a future electron-ion collider and show that this process has the power to disentangle the contributions of the interaction with a specific number of nucleons $k$, in particular, with two …
Coherent elastic neutrino-nucleus scattering (CE$ν$NS), a process recently measured for the first time at ORNL's Spallation Neutron Source, is directly sensitive to the weak form factor of the nucleus. The European Spallation Source (ESS), presently under construction, will generate the most intense pulsed neutrino flux suitable for the detection of CE$ν$NS. In this paper we quantify its potential to determine the root mean square radius of the point-neutron distribution, for a variety of target nuclei and a suite of detectors. To put our results in context we also derive, for the first time, …
Using the data on coherent $J/ψ$ photoproduction in Pb-Pb ultraperipheral collisions (UPCs) obtained in Runs 1 and 2 at the Large Hadron Collider (LHC), we determined with a good accuracy the nuclear suppression factor of $S_{Pb}(x)$ in a wide range of the momentum fraction $x$, $10^{-5} \leq x \leq 0.04$. In the small-$x$ region $x < 10^{-3}$, our $χ^2$ fit favors a flat form of $S_{Pb}(x) \approx 0.6$ with approximately a 5% accuracy for $x=6 \times 10^{-4} - 10^{-3} $ and a 25% error at $x=10^{-4}$. At the same time, uncertainties of the fit do not exclude a slow decrease of $S_{Pb}(x)$ in …
The differential cross section of coherent photo-production of heavy quarkonia on nuclear targets is calculated within the QCD color dipole formalism. The higher-twist nuclear shadowing corresponding to the $\bar QQ$ Fock component of the photon, is calculated including the correlation between dipole orientation $\vec r$ and impact parameter of a collision $\vec b$, which is related to the transverse momentum transfer via Fourier transform. We also included the leading twist gluon shadowing corresponding to higher Fock components of the photon containing gluons, which have specifically short c…
The cross section for coherent elastic neutrino-nucleus scattering (CE$ν$NS) depends on the response of the target nucleus to the external current, in the Standard Model (SM) mediated by the exchange of a $Z$ boson. This is typically subsumed into an object called the weak form factor of the nucleus. Here, we provide results for this form factor calculated using the large-scale nuclear shell model for a wide range of nuclei of relevance for current CE$ν$NS experiments, including cesium, iodine, argon, fluorine, sodium, germanium, and xenon. In addition, we provide the responses needed to captu…