arXiv 1803.096132018-03-26nucl-th

Three-nucleon force in chiral EFT with explicit $Δ(1232)$ degrees of freedom: Longest-range contributions at fourth order

H. Krebs, A. M. Gasparyan, E. Epelbaum

备注：: 38 pages, 12 figures
发表信息：: Phys. Rev. C 98, 014003 (2018)
DOI：: 10.1103/PhysRevC.98.014003

英文摘要：

We analyze the longest-range two-pion exchange contributions to the three-nucleon force at leading-loop order in the framework of heavy-baryon chiral effective field theory with explicit $Δ(1232)$ degrees of freedom. All relevant low-energy constants which appear in the calculation are determined from pion-nucleon scattering. Comparing our results with the ones obtained in the $Δ$-less theory at N4LO, we find effects of the $Δ$ isobar for this particular topology to be rather well represented in terms of resonance saturation of various low-energy constants in the $Δ$-less approach.

机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。

阅读原文

阅读 PDF ↗

arXiv 页面 ↗HTML 原文 ↗

本文内容

英文摘要相关论文

机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。

继续探索

相关论文

Lee-Yang-inspired functional including contributions to fourth order in effective field theory

In the last years, a new family of energy density functionals directly inspired by effective field theory (EFT) has been developed, among which the ELYO (extended Lee-Yang Orsay) functional. In this paper, a new extension of ELYO that includes the recently calculated fourth-order EFT terms is presented. Compared to the previous version, the description of neutron-drop energies slightly degrades for a harmonic trap $\hbarω=10$ MeV -- yet remaining reasonable -- , but improves for $\hbarω=5$ MeV. Furthermore, the obtained neutron effective mass agrees significantly better with \textit{ab-initio}…

2022-11-29nucl-th

Exploring Bayesian parameter estimation for chiral effective field theory using nucleon-nucleon phase shifts

We recently developed a Bayesian framework for parameter estimation in general effective field theories. Here we present selected results from using that framework to estimate parameters with a nucleon-nucleon (NN) potential derived using chiral effective field theory ($χ$EFT): the semi-local NN potential of Epelbaum, Krebs, and Meißner (EKM). There are many NN scattering data, up to high energies, and with rather small errors, so imposing a penalty for unnatural low-energy constants (LECs) usually has a small effect on the fits. In contrast, we have found that including an estimate of higher …

2018-08-24nucl-th

手征有效场理论核子-核子部分直至四阶低能常数的贝叶斯估计

Bayesian estimation of the low-energy constants up to fourth order in the nucleon-nucleon sector of chiral effective field theory

研究使用贝叶斯方法和HMC采样推断手征有效场理论核子-核子相互作用直至N3LO的LECs后验分布，发现经验点估计与贝叶斯结果一致，且考虑截断误差需达N2LO才能可靠检测同位旋破缺效应。

2024-07-26nucl-th

Analyzing rotational bands in odd-mass nuclei using Effective Field Theory and Bayesian methods

We recently developed an Effective Field Theory (EFT) for rotational bands in odd-mass nuclei. Here we use EFT expressions to perform a Bayesian analysis of data on the rotational energy levels of $^{99}$Tc, ${}^{155,157}$Gd, ${}^{159}$Dy, ${}^{167, 169}$Er, ${}^{167, 169}$Tm, ${}^{183}$W, ${}^{235}$U and ${}^{239}$Pu. The error model in our Bayesian analysis includes both experimental and EFT truncation uncertainties. It also accounts for the fact that low-energy constants (LECs) at even and odd orders are expected to have different sizes. We use Markov Chain Monte Carlo (MCMC) sampling to ex…

2022-03-03nucl-th

挑战手征有效场论：氚的β衰变

Challenging chiral EFT with tritium beta decay

M. Smoluchowski Institute of Physics, Faculty of Physics, Astronomy and Applied Computer Science, Jagiellonian University（雅盖隆大学物理、天文学与应用科学学院 M.Smoluchowski 物理研究所）；Doctoral School of Exact and Natural Sciences, Jagiellonian University（雅盖隆大学精确与自然科学研究生院）；Ruhr-Universität Bochum, Fakultät für Physik und Astronomie, Institut für Theoretische Physik II（波鸿鲁尔大学物理与天文学院理论物理第二研究所）

使用LENPIC相互作用在手征有效场论中研究氚β衰变至N2LO，通过核子-氘散射固定低能常数D，发现无参数预测的Gamow-Teller约化矩阵元显著高估实验值，表明存在精细调节和较大高阶修正。

2026-06-26nucl-th

手征 EFT 中核子的引力形状因子与单π介子引力产生

Gravitational form factors of the nucleon and one pion graviproduction in chiral EFT

本文在手征 EFT 中计算至四阶核子引力形状因子，揭示 Δ 共振的重要性，并以十二个跃迁形状因子参数化 $N\to Nπ$ 矩阵元、计算至三阶树图贡献。

2024-01-24hep-phhep-thnucl-th

更多相关论文收起更多论文

Quantifying uncertainties and correlations in the nuclear-matter equation of state

We perform statistically rigorous uncertainty quantification (UQ) for chiral effective field theory ($χ$EFT) applied to infinite nuclear matter up to twice nuclear saturation density. The equation of state (EOS) is based on high-order many-body perturbation theory calculations with nucleon-nucleon and three-nucleon interactions up to fourth order in the $χ$EFT expansion. From these calculations our newly developed Bayesian machine-learning approach extracts the size and smoothness properties of the correlated EFT truncation error. We then propose a novel extension that uses multitask machine l…

2021-01-07astro-ph.HEhep-phnucl-ex

How well do we know the neutron-matter equation of state at the densities inside neutron stars? A Bayesian approach with correlated uncertainties

We introduce a new framework for quantifying correlated uncertainties of the infinite-matter equation of state derived from chiral effective field theory ($χ$EFT). Bayesian machine learning via Gaussian processes with physics-based hyperparameters allows us to efficiently quantify and propagate theoretical uncertainties of the equation of state, such as $χ$EFT truncation errors, to derived quantities. We apply this framework to state-of-the-art many-body perturbation theory calculations with nucleon-nucleon and three-nucleon interactions up to fourth order in the $χ$EFT expansion. This produce…

2021-01-07astro-ph.HEhep-phnucl-ex