arXiv: Nuclear Theory最新文献

Equation of state and radial oscillations of neutron stars 中子星的状态方程和径向振荡

arXiv: Nuclear Theory Pub Date : 2021-01-19 DOI: 10.1103/PhysRevD.103.103003

T. Sun, Zi-Yue Zheng, Huan Chen, G. Burgio, H. Schulze

引用次数: 5

Get on the BAND Wagon: a Bayesian framework for quantifying model uncertainties in nuclear dynamics 登上BAND Wagon:量化核动力学模型不确定性的贝叶斯框架

arXiv: Nuclear Theory Pub Date : 2020-12-14 DOI: 10.1088/1361-6471/abf1df

D. Phillips, R. Furnstahl, U. Heinz, T. Maiti, W. Nazarewicz, F. Nunes, M. Plumlee, M. Pratola, S. Pratt, F. Viens, Stefan M. Wild

引用次数: 47

Coupling dynamical and statistical mechanisms for baryonic cluster production in nucleus collisions of intermediate and high energies 中高能核碰撞重子团簇产生的耦合动力学和统计机制

arXiv: Nuclear Theory Pub Date : 2020-12-14 DOI: 10.1103/PhysRevC.103.064602

A. Botvina, N. Buyukcizmeci, M. Bleicher

{"title":"Coupling dynamical and statistical mechanisms for baryonic cluster production in nucleus collisions of intermediate and high energies","authors":"A. Botvina, N. Buyukcizmeci, M. Bleicher","doi":"10.1103/PhysRevC.103.064602","DOIUrl":"https://doi.org/10.1103/PhysRevC.103.064602","url":null,"abstract":"Central nucleus-nucleus collisions produce many new baryons and the nuclear clusters can be formed from these species. The phenomenological coalescence models were sufficiently good for description of light nuclei yields in a very broad range of collision energies. We demonstrate that in reality the coalescence process can be considered as 1) the formation of primary diluted excited baryon clusters and 2) their following statistical decay leading to the final cold fragment production. We argue that the formation of such excited systems from the interacting baryons is a natural consequence of the nuclear interaction at subnuclear densities resulting in the nuclear liquid-gas type phase transition in finite systems. In this way one can provide a consistent interpretation of the experimental fragment yields (FOPI data) including the important collision energy dependence in relativistic ion reactions. We investigate the regularities of this new kind of fragment production, for example, their yield, isospin, and kinetic energy characteristics. A generalization of such a clusterization mechanism for hypernuclear matter is suggested. The isotope yields and particle correlations should be adequate for studying these phenomena.","PeriodicalId":8463,"journal":{"name":"arXiv: Nuclear Theory","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75111430","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Extrapolating from neural network models: a cautionary tale 从神经网络模型推断:一个警世故事

arXiv: Nuclear Theory Pub Date : 2020-12-11 DOI: 10.1088/1361-6471/abf08a

A. Pastore, M. Carnini

引用次数: 12

New results about the canonical transformation for boson operators 关于玻色子算子正则变换的新结果

arXiv: Nuclear Theory Pub Date : 2020-12-09 DOI: 10.1142/S0218301321500191

C. Raduta, A. Raduta

引用次数: 0

Nuclear shape transitions and elastic magnetic electron scattering 核形状跃迁和弹性磁电子散射

arXiv: Nuclear Theory Pub Date : 2020-12-09 DOI: 10.1103/PhysRevC.103.014303

B. Hernandez, P. Sarriguren, O. Moreno, E. Moya de Guerra, D. N. Kadrev, A. N. Antonov

{"title":"Nuclear shape transitions and elastic magnetic electron scattering","authors":"B. Hernandez, P. Sarriguren, O. Moreno, E. Moya de Guerra, D. N. Kadrev, A. N. Antonov","doi":"10.1103/PhysRevC.103.014303","DOIUrl":"https://doi.org/10.1103/PhysRevC.103.014303","url":null,"abstract":"Backward elastic electron scattering from odd-A nuclear targets is characterized by magnetic form factors containing precise information on the nuclear structure. We study the sensitivity of the magnetic form factors to structural effects related to the evolution and shape transitions in both isotopic and isotonic chains. Calculations of magnetic form factors are performed in the plane-wave Born approximation. The nuclear structure is obtained from a deformed self-consistent mean-field calculation based on a Skyrme HF+BCS formalism. Collective effects are included in the cranking approximation, whereas nucleon-nucleon correlations are taken into account in the coherent density fluctuation model. The evolution of the magnetic form factors is found to exhibit signatures of shape transitions that show up in selected isotopic and isotonic chains involving both stable and unstable nuclei. Several cases are identified as suitable candidates for showing such fingerprints of shape transitions. A new generation of electron scattering experiments involving electron-radioactive beam colliders will be available in the near future, leading to a renewed interest in this field.","PeriodicalId":8463,"journal":{"name":"arXiv: Nuclear Theory","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74047949","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

Constraining the nonanalytic terms in the isospin-asymmetry expansion of the nuclear equation of state 约束核状态方程同位旋不对称展开中的非解析项

arXiv: Nuclear Theory Pub Date : 2020-12-03 DOI: 10.1103/PhysRevC.103.064002

Pengsheng Wen, J. Holt

{"title":"Constraining the nonanalytic terms in the isospin-asymmetry expansion of the nuclear equation of state","authors":"Pengsheng Wen, J. Holt","doi":"10.1103/PhysRevC.103.064002","DOIUrl":"https://doi.org/10.1103/PhysRevC.103.064002","url":null,"abstract":"We examine the properties of the isospin-asymmetry expansion of the nuclear equation of state from chiral two- and three-body forces. We focus on extracting the high-order symmetry energy coefficients that consist of both normal terms (occurring with even powers of the isospin asymmetry) as well as terms involving the logarithm of the isospin asymmetry that are formally nonanalytic around the expansion point of isospin-symmetric nuclear matter. These coefficients are extracted from numerically precise perturbation theory calculations of the equation of state coupled with a new set of finite difference formulas that achieve stability by explicitly removing the effects of higher-order terms in the expansion. We consider contributions to the symmetry energy coefficients from both two- and three-body interactions. It is found that the coefficients of the logarithmic terms are generically larger in magnitude than those of the normal terms from second-order perturbation theory diagrams, but overall the normal terms give larger contributions to the ground state energy. The high-order isospin-asymmetry terms are especially relevant at large densities where they affect the proton fraction in beta-equilibrium matter.","PeriodicalId":8463,"journal":{"name":"arXiv: Nuclear Theory","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87969453","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Nuclear pasta structures and symmetry energy 核面食结构和对称能

arXiv: Nuclear Theory Pub Date : 2020-12-02 DOI: 10.1103/PhysRevC.103.055812

C. Xia, T. Maruyama, N. Yasutake, T. Tatsumi, Y. Zhang

{"title":"Nuclear pasta structures and symmetry energy","authors":"C. Xia, T. Maruyama, N. Yasutake, T. Tatsumi, Y. Zhang","doi":"10.1103/PhysRevC.103.055812","DOIUrl":"https://doi.org/10.1103/PhysRevC.103.055812","url":null,"abstract":"In the framework of the relativistic mean field model with Thomas-Fermi approximation, we study the structures of low density nuclear matter in a three-dimensional geometry with reflection symmetry. The numerical accuracy and efficiency are improved by expanding the mean fields according to fast cosine transformation and considering only one octant of the unit cell. The effect of finite cell size is treated carefully by searching for the optimum cell size. Typical pasta structures (droplet, rod, slab, tube, and bubble) arranged in various crystalline configurations are obtained for both fixed proton fractions and $beta$-equilibration. It is found that the properties of droplets/bubbles are similar in body-centered cubic (BCC) and face-centered cubic (FCC) lattices, where the FCC lattice generally becomes more stable than BCC lattice as density increases. For the rod/tube phases, the honeycomb lattice is always more stable than the simple one. By introducing an $omega$-$rho$ cross coupling term, we further examine the pasta structures with a smaller slope of symmetry energy $L = 41.34$ MeV, which predicts larger onset densities for core-crust transition and non-spherical nuclei. Such a variation due to the reduction of $L$ is expected to have impacts on various properties in neutron stars, supernova dynamics, and binary neutron star mergers.","PeriodicalId":8463,"journal":{"name":"arXiv: Nuclear Theory","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89453180","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

Compression Modulus and Symmetry Energy of Nuclear Matter with KIDS Density Functional KIDS密度泛函下核物质的压缩模量和对称能

arXiv: Nuclear Theory Pub Date : 2020-12-02 DOI: 10.3938/NPSM.71.242

Hana Gil, C. H. Hyun

引用次数: 4

Intrinsic correlations among characteristics of neutron-rich matter imposed by the unbound nature of pure neutron matter 纯中子物质的非束缚性质所施加的富中子物质特性之间的内在关联

arXiv: Nuclear Theory Pub Date : 2020-12-02 DOI: 10.1103/PHYSREVC.103.034607

Bao-Jun Cai, Bao-An Li

{"title":"Intrinsic correlations among characteristics of neutron-rich matter imposed by the unbound nature of pure neutron matter","authors":"Bao-Jun Cai, Bao-An Li","doi":"10.1103/PHYSREVC.103.034607","DOIUrl":"https://doi.org/10.1103/PHYSREVC.103.034607","url":null,"abstract":"The unbound nature of pure neutron matter (PNM) requires intrinsic correlations between the symmetric nuclear matter (SNM) EOS parameters (incompressibility $K_0$, skewness $J_0$ and kurtosis $I_0$) and those (slope $L$, curvature $K_{rm{sym}}$ and skewness $J_{rm{sym}}$) characterizing the symmetry energy independent of any nuclear many-body theory. We investigate these intrinsic correlations and their applications in better constraining the poorly known high-density behavior of nuclear symmetry energy. Several novel correlations connecting the characteristics of SNM EOS with those of nuclear symmetry energy are found. In particular, at the lowest-order of approximations, the bulk parts of the slope $L$, curvature $K_{rm{sym}}$ and skewness $J_{rm{sym}}$ of the symmetry energy are found to be $Lapprox K_0/3, K_{rm{sym}}approx LJ_0/2K_0$ and $J_{rm{sym}}approx I_0L/3K_0$, respectively. High-order corrections to these simple relations can be written in terms of the small ratios of high-order EOS parameters. The resulting intrinsic correlations among some of the EOS parameters reproduce very nicely their relations predicted by various microscopic nuclear many-body theories and phenomenological models constrained by available data of terrestrial experiments and astrophysical observations in the literature. The unbound nature of PNM is fundamental and the required intrinsic correlations among the EOS parameters characterizing both the SNM EOS and symmetry energy are universal. These intrinsic correlations provide a novel and model-independent tool not only for consistency checks but also for investigating the poorly known high-density properties of neutron-rich matter by using those with smaller uncertainties.","PeriodicalId":8463,"journal":{"name":"arXiv: Nuclear Theory","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87237118","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 6