Halos epitomize the fascinating interplay between weak binding, shell evolution, and deformation effects, especially in nuclei near the drip line. In this Letter, we apply the state-of-the-art \textit{ab initio} valence-space in-medium similarity renormalization group approach to predict potential candidates for one- and two-neutron halo in the intermediate-mass region. Notably, we use spectroscopic factors (SF) and two-nucleon amplitudes (TNA) as criteria for suggesting one- and two-neutron halo candidates, respectively. This approach is not only theoretically sound but also amenable to experimental validation. Our research focuses on Mg, Al, Si, P, and S neutron-drip-line nuclei, offering systematic predictions of neutron halo candidates in terms of separation energies, SF (TNA), and average occupation. The calculation suggests the ground states of $^{40,42,44,46}$Al, $^{41,43,45,47}$Si, $^{46,48}$P, and $^{47,49}$S are promising candidates for one-neutron halos, while $^{40,42,44,46}$Mg, $^{45,47}$Al, $^{46,48}$Si, $^{49}$P, and $^{50}$S may harbor two-neutron halos. In addition, the relative mean-square neutron radius between halo nuclei and \textit{inner core} is calculated for suggested potential neutron halos. Finally, the relations of halo formations and shell evolution are discussed.
$\boldsymbol{\textit{Ab initio}}$ $nα$ scattering using the Efros method
Institute of Modern Physics, Chinese Academy of Sciences（中国科学院近代物理研究所）；College of Physics and Engineering, Henan University of Science and Technology（河南科技大学物理与工程学院）；State Key Laboratory of Heavy Ion Science and Technology, Institute of Modern Physics, Chinese Academy of Sciences（中国科学院近代物理研究所重离子科学和技术国家重点实验室）；Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University（莫斯科国立大学索别利茨基核物理研究所）；Department of Physics and Astronomy, Iowa State University（爱荷华州立大学物理与天文系）
Based on the spectator expansion of the multiple scattering series we employ a chiral next-to-next-to-leading order (NNLO) nucleon-nucleon interaction on the same footing in the structure as well as in the reaction calculation to obtain an in leading-order consistent effective potential for nucleon-nucleus elastic scattering, which includes the spin of the struck target nucleon. As an example we present proton scattering off $^{12}$C.
Toward $\textit{Ab Initio}$ Quantum Simulations of Atomic Nuclei Using Noisy Qubits
State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University（北京大学物理学院核物理与技术国家重点实验室）；Southern Center for Nuclear-Science Theory (SCNT), Institute of Modern Physics, Chinese Academy of Sciences（中国科学院近代物理研究所南方核科学理论中心）
A new Skyrme functional devised to account well for standard nuclear properties as well as for spin and spin-isospin properties is presented. The main novelty of this work relies on the introduction of tensor terms guided by \textit{ab initio} relativistic Brueckner-Hartree-Fock calculations of neutron-proton drops. The inclusion of tensor term does not decrease the accuracy in describing bulk properties of nuclei, experimental data of some selected spherical nuclei such as binding energies, charge radii, and spin-orbit splittings can be well fitted. The new functional is applied to the invest…
First \textit{ab initio} calculations of first-forbidden $β$ transitions in the reactor antineutrino anomaly
Peking University（北京大学）；School of Physics, and State Key Laboratory of Nuclear Physics and Technology, Peking University（北京大学物理学院，核物理与技术国家重点实验室）；Institute of Modern Physics, Fudan University（复旦大学现代物理研究所）；Shanghai Research Center for Theoretical Nuclear Physics, NSFC and Fudan University（上海理论核物理研究中心，NSFC和复旦大学）；Southern Center for Nuclear-Science Theory, Institute of Modern Physics, Chinese Academy of Sciences（中国科学院现代物理研究所南方核科学理论中心）
Starting from the relativistic realistic nucleon-nucleon ($NN$) interactions, a newly developed relativistic \textit{ab initio} method, i.e., the relativistic Brueckner-Hartree-Fock (RBHF) theory in the full Dirac space is employed to study the neutron star properties. First, the one-to-one correspondence relation for gravitational redshift and mass is established and used to infer the mass of isolated neutron stars combining the gravitational redshift measurements. Next, the ratio of the moment of inertia $I$ to $MR^2$ as a function of the compactness $M/R$ is obtained, which is consistent wi…
$^6$He structure from semiclassical 3D models based on $\textit{ab initio}$ spatial correlations
Iowa State University（爱荷华州立大学）；Instituto Tecnológico de Aeronáutica（航空技术学院）；Henan University of Science and Technology（河南科技大学）；Chinese Academy of Sciences（中国科学院）
\textit{Ab initio} study of spectroscopic factors in $^{48}$K and neighboring $N=28$ isotones
Advanced Energy Science and Technology Guangdong Laboratory（广东先进能源科学与技术实验室）；Institute of Modern Physics, Chinese Academy of Sciences（中国科学院近代物理研究所）；Heavy Ion Science and Technology Key Laboratory（重离子科学与技术重点实验室）；School of Nuclear Science and Technology, University of Chinese Academy of Sciences（中国科学技术大学核科学与技术学院）；Southern Center for Nuclear-Science Theory (SCNT)（南方核科学理论中心）
New energy-density functionals (EDFs) inspired by effective-field theories (EFTs) have been recently proposed. The present work focuses on three of such functionals which were developed to produce satisfactory equations of state for nuclear matter. We aim to extend these functionals to treat finite systems including a spin-orbit contribution and pairing correlations. We illustrate here a first step towards this direction, namely a generalization of such functionals tailored to perform applications to neutron gases confined in harmonic traps. Sets of available \textit{ab initio} results are use…
Halo structure of $^6$He from $\textit{ab initio}$ two-nucleon spatial correlations
Iowa State University（爱荷华州立大学）；Lawrence Livermore National Laboratory（劳伦斯利弗莫尔国家实验室）；Instituto Tecnológico de Aeronáutica（航空技术学院）；Henan University of Science and Technology（河南科技大学）；Chinese Academy of Sciences（中国科学院）
We report a comprehensive study of $^{10-14}$B isotopes within the \textit{ab-initio} no-core shell model (NCSM) using realistic nucleon-nucleon (\textit{NN}) interactions. In particular, we have applied the inside non-local outside Yukawa (INOY) interaction to study energy spectra, electromagnetic properties and point-proton radii of the boron isotopes. The NCSM results with the charge-dependent Bonn 2000 (CDB2K), the chiral next-to-next-to-next-to-leading order (N$^3$LO) and optimized next-to-next-to-leading order (N$^2$LO$_{opt}$) interactions are also reported. We have reached basis sizes …
Full Configuration Interaction Quantum Monte Carlo for Accurate $\textit{Ab Initio}$ Nuclear Structure Calculations
School of Physics, and State Key Laboratory of Nuclear Physics and Technology, Peking University（北京大学物理学院，核物理与技术国家重点实验室）；Southern Center for Nuclear-Science Theory (SCNT), Institute of Modern Physics, Chinese Academy of Sciences（中国科学院近代物理研究所，南方核科学理论中心）；Max Planck Institute for Solid State Research（马克斯·普朗克固体研究所）；Department of Chemistry, University of Cambridge（剑桥大学化学系）
The $A=4$ nuclei, i.e., $^4$H, $^4$He and $^4$Li, establish an interesting isospin $T=1$ isobaric system. $^4$H and $^4$Li are unbound broad resonances, whereas $^4$He is deeply bound in its ground state but unbound in all its excited states. The present situation is that experiments so far have not given consistent data on the resonances. Few-body calculations have well studied the scatterings of the $4N$ systems. In the present work, we provide many-body calculations of the broad resonance structures, in an \textit{ab initio} framework with modern realistic interactions. It occurs that, inde…
Full configuration interaction quantum Monte Carlo for accurate $\textit{ab initio}$ nuclear structure calculations: algorithms and calculation details
School of Physics, and State Key Laboratory of Nuclear Physics and Technology, Peking University（北京大学物理学院，核物理与技术国家重点实验室）；Southern Center for Nuclear-Science Theory (SCNT), Institute of Modern Physics, Chinese Academy of Sciences（中国科学院近代物理研究所南方核科学理论中心(SCNT)）；Max Planck Institute for Solid State Research（马克斯·普朗克固体研究所）；Department of Chemistry, University of Cambridge（剑桥大学化学系）
Chiral three-nucleon forces for the new local position-space two-nucleon potential in $\textit{ab initio}$ many-body calculations
School of Physics, and State Key Laboratory of Nuclear Physics and Technology, Peking University（北京大学物理学院及核物理与核技术国家重点实验室）；Institute of Modern Physics, Chinese Academy of Sciences（中国科学院近代物理研究所）；Southern Center for Nuclear-Science Theory (SCNT), Institute of Modern Physics, Chinese Academy of Sciences（中国科学院近代物理研究所南方核科学理论中心）
Knockout reactions with heavy ion targets in inverse kinematics, as well as "quasi-free" (p,2p) and (p,pn) reactions are useful tools for nuclear spectroscopy. We report calculations on \textit{ab-initio} many-body wavefunctions based on the no-core shell model to study the nucleon removal reactions in light nuclei, including beryllium, carbon, and oxygen isotopic chains, and explore the importance of using an \textit{ab-initio} method. Our study helps clarifying how the extraction of spectroscopic factors from the experiments depend on the details of the many-body wavefunctions being probed. …
New \textit{ab initio} calculations of the isotopic reactor antineutrino fluxes are provided with exact numerical calculations of the lepton wave functions, assuming all the decay branches are allowed GT transitions. We illustrate that the analytical Fermi function and finite size effect each could have the largest spectral deviation of $\mathcal{O}(10\%)$, whereas the effect of their combination could result in spectral deviations at the level of 5%-10%. Meanwhile, we also find that several forms of the extended charge distributions have negligible effects on the spectral variation. Using the…
The determination of the electron neutrino mass by electron capture in $^{163}$Ho relies on a precise understanding of the deexcitation of a core hole after an electron capture event. We here present an \textit{ab intio} calculation of the electron capture spectrum in $^{163}$Ho, including all intra-atomic decay channels into bound-states. We use theoretical methods developed for the calculation of core level spectroscopy on correlated electron compounds. Our comparison critically tests the reality of these theories. We find that relativistic interactions beyond the Dirac equation, i.e. quantu…
