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Nucleon weak matrix elements can be extracted from nucleon correlation functions with lattice QCD simulations. The signal-to-noise ratio prohibits the analysis at large source-sink separations and as a consequence, excited state…

High Energy Physics - Lattice · Physics 2024-06-03 Lorenzo Barca , Gunnar Bali , Sara Collins

The self-consistent proton-neutron quasiparticle random phase approximation approach is employed to calculate $\beta$-decay half-lives of neutron-rich even-even nuclei with $8\leqslant Z \leqslant 30$. A newly proposed nonlinear…

Nuclear Theory · Physics 2016-03-23 Z. Y. Wang , Z. M. Niu , Y. F. Niu , J. Y. Guo

Background: The major challenge for nuclear theory is to describe and predict global properties and collective modes of atomic nuclei. Of particular interest is the response of the nucleus to a time-dependent external field that impacts the…

Nuclear Theory · Physics 2013-06-18 Nobuo Hinohara , Markus Kortelainen , Witold Nazarewicz

Content-adaptive compression is crucial for enhancing the adaptability of the pre-trained neural codec for various contents. Although these methods have been very practical in neural image compression (NIC), their application in neural…

Image and Video Processing · Electrical Eng. & Systems 2024-09-05 Zhenghao Chen , Luping Zhou , Zhihao Hu , Dong Xu

Distortions in a family of conjugated polymers are studied within two complementary approaches, i.e. within a many-body Valence Bond (VB) approach using a transfer matrix technique to treat the Heisenberg model of the systems, and also in…

Condensed Matter · Physics 2009-10-30 M. A. Garcia-Bach , R. Valenti , D. J. Klein

We apply the Coherent Potential Approximation (CPA) to a simple extended Hubbard model with a nearest and next nearest neighbour hopping for disordered superconductors with s-, d- and p-wave pairing. We show how the Van Hove singularities…

Superconductivity · Physics 2015-06-24 G. Litak

Within the one-loop approximation of baryon chiral perturbation theory we calculate all one-pion and two-pion exchange contributions to the nucleon-nucleon interaction. In fact we construct the elastic NN-scattering amplitude up to and…

Nuclear Theory · Physics 2009-10-30 N. Kaiser , R. Brockmann , W. Weise

The lowest quadrupole $\gamma$-vibrational $K^{\pi}=2^+$ states in axially deformed rare-earth (Nd, Sm, Gd, Dy, Er, Yb, Hf, W) and actinide (U) nuclei are systematically investigated within the separable random-phase-approximation (SRPA)…

Nuclear Theory · Physics 2017-06-05 V. O. Nesterenko , V. G. Kartavenko , W. Kleinig , R. V. Jolos , J. Kvasil , P. -G. Reinhard

Variational quantum algorithms involve training parameterized quantum circuits using a classical co-processor. An important variational algorithm, designed for combinatorial optimization, is the quantum approximate optimization algorithm.…

We study the ability of variational approaches based on self-consistent mean-field and beyond-mean-field methods to reproduce exact energies and electromagnetic properties of the nuclei defined within the $sd$-shell valence space using the…

Nuclear Theory · Physics 2021-11-15 Adrián Sánchez-Fernández , Benjamin Bally , Tomás R. Rodríguez

Sparse Principal Component Analysis (sPCA) is a cardinal technique for obtaining combinations of features, or principal components (PCs), that explain the variance of high-dimensional datasets in an interpretable manner. This involves…

Optimization and Control · Mathematics 2025-12-02 Ryan Cory-Wright , Jean Pauphilet

In the context of estimating stochastically ordered distribution functions, the pool-adjacent-violators algorithm (PAVA) can be modified such that the computation times are reduced substantially. This is achieved by studying the dependence…

Statistics Theory · Mathematics 2023-01-04 Alexander Henzi , Alexandre Moesching , Lutz Duembgen

Relativistic coupled-cluster (RCC) theory at the singles and doubles approximation has been implemented to estimate nuclear spin dependent (NSD) parity violating (PV) electric dipole (E1) transition amplitudes ($E1_{PV}^{NSD}$) among…

Atomic Physics · Physics 2024-08-19 A. Chakraborty , B. K. Sahoo

The self-consistent quasiparticle random-phase approximation (QRPA) approach is formulated in the canonical single-nucleon basis of the relativistic Hatree-Fock-Bogoliubov (RHFB) theory. This approach is applied to study the isobaric analog…

Nuclear Theory · Physics 2017-04-12 Z. M. Niu , Y. F. Niu , H. Z. Liang , W. H. Long , J. Meng

We study the extension of our translationally invariant treatment of few-body nuclear systems to heavier nuclei. At the same time we also introduce state-dependent correlation operators. Our techniques are tailored to those nuclei that can…

Nuclear Theory · Physics 2009-10-30 R. Guardiola , P. I. Moliner , J. Navarro , R. F. Bishop , A. Puente , Niels R. Walet

Principal Component analysis (PCA) is a useful statistical technique that is commonly used for multivariate analysis of correlated variables. It is usually applied as a dimension reduction method: the top principal components (PCs)…

Principal component analysis (PCA) is very popular to perform dimension reduction. The selection of the number of significant components is essential but often based on some practical heuristics depending on the application. Only few works…

Machine Learning · Statistics 2017-09-19 Clément Elvira , Pierre Chainais , Nicolas Dobigeon

Principal Component Analysis (PCA) and K-means constitute fundamental techniques in multivariate analysis. Although they are frequently applied independently or sequentially to cluster observations, the relationship between them, especially…

Machine Learning · Statistics 2025-12-02 Victor Saquicela , Kenneth Palacio-Baus , Mario Chifla

While limited coupled cluster theory is \textit{formally} nonvariational, it is not broadly appreciated whether this is a major issue \textit{in practice}. We carried out a detailed comparison with \textit{de facto} full CI energies for a…

Chemical Physics · Physics 2024-10-03 Jan M. L. Martin , Emmanouil Semidalas

A general algorithm for computing the quadrupole-hyperfine effects in the rovibrational spectra of polyatomic molecules is presented for the case of ammonia (NH$_3$). The method extends the general variational approach TROVE by adding the…

Chemical Physics · Physics 2017-10-25 Andrey Yachmenev , Jochen Küpper