English
Related papers

Related papers: RPA puzzle in C(12) weak decay processes

200 papers

We examine the violation of the Pauli exclusion principle in the Quasiparticle Random Phase Approximation (QRPA) calculation of the two-neutrino double beta decay matrix elements, which has its origin in the quasi-boson approximation. For…

Nuclear Theory · Physics 2009-10-30 J. Schwieger , F. Šimkovic , Amand Faessler

We use the random phase approximation to describe the muon capture rate on ${}^{44}$Ca,${}^{48}$Ca, ${}^{56}$Fe, ${}^{90}$Zr, and ${}^{208}$Pb. With ${}^{40}$Ca as a test case, we show that the Continuum Random Phase Approximation (CRPA)…

Nuclear Theory · Physics 2009-11-06 E. Kolbe , K. Langanke , P. Vogel

Quasiparticle random-phase approximation (QRPA) is applied to two nuclei, and overlap of the QRPA excited states based on the different nuclei is calculated. The aim is to calculate the overlap of intermediate nuclear states of the…

Nuclear Theory · Physics 2015-06-05 J. Terasaki

In recent work, robust Principal Components Analysis (PCA) has been posed as a problem of recovering a low-rank matrix $\mathbf{L}$ and a sparse matrix $\mathbf{S}$ from their sum, $\mathbf{M}:= \mathbf{L} + \mathbf{S}$ and a provably exact…

Information Theory · Computer Science 2023-07-19 Jinchun Zhan , Namrata Vaswani

In view of the recent experiments on neutrino oscillations performed by the LSND and KARMEN collaborations as well as of future experiments, we present new theoretical results of the flux averaged $^{12}C(\nu_e,e^-)^{12}N$ and…

Nuclear Theory · Physics 2009-11-06 C. Volpe , N. Auerbach , G. Colø , T. Suzuki , N. Van Giai

Estimates of nuclear matrix elements for neutrinoless double beta decay (0nu2beta) based on the quasiparticle random phase approximations (QRPA) are affected by theoretical uncertainties, which can be substantially reduced by fixing the…

In our subgroup, we focused on penguin physics from various different angles. Our discussions included: (1) A method to extract one of the angles of the unitarity triangle $\phi_2$; (2) Methods to extract $\phi_3$ from $B\to K\pi$ decays;…

High Energy Physics - Phenomenology · Physics 2009-09-25 A. I. Sanda

Calculating weak decay rates under stellar conditions for studying presupernova evolution of massive stars is a challenging task. Here we show the importance of odd A nuclei for presupernova simulations. In order to calculate the required…

Nuclear Theory · Physics 2025-02-28 Muhammad Riaz , Jameel-Un Nabi , Muhammad Majid

The Quasi-Elastic contribution of the nuclear inclusive electron scattering model developed in Nucl. Phys. A 627 (1997) 543 is extended to the study of electroweak Charged Current induced nuclear reactions, at intermediate energies of…

Nuclear Theory · Physics 2007-05-23 J. Nieves , J. E. Amaro , M. Valverde , E. Oset

The structure and the weak interaction mediated rates of the heavy waiting point (WP) nuclei $^{80}$Zr, $^{84}$Mo, $^{88}$Ru, $^{92}$Pd and $^{96}$Cd along $N = Z$ line were studied within the interacting boson model-1 (\mbox{IBM-1}) and…

Nuclear Theory · Physics 2025-05-07 Jameel-Un Nabi , Mahmut Boyukata

The robust PCA problem, wherein, given an input data matrix that is the superposition of a low-rank matrix and a sparse matrix, we aim to separate out the low-rank and sparse components, is a well-studied problem in machine learning. One…

Machine Learning · Computer Science 2017-07-06 U. N. Niranjan , Arun Rajkumar , Theja Tulabandhula

The $\nu_e-^{56}$Fe cross section is evaluated in the projected quasiparticle random phase approximation (PQRPA). This model solves the puzzle observed in RPA for nuclei with mass around $^{12}$C, because it is the only RPA model that…

Nuclear Theory · Physics 2008-11-26 A. R. Samana , C. A. Bertulani

A process centric view of robust PCA (RPCA) allows its fast approximate implementation based on a special form o a deep neural network with weights shared across all layers. However, empirically this fast approximation to RPCA fails to find…

Neural and Evolutionary Computing · Computer Science 2014-12-30 Maximilian Karl , Christian Osendorfer

The neutron direct radiative capture (DRC) process is investigated, highlighting the role of incident p-wave neutrons. A set of calculations is shown for the 12-C(n,gamma) process at incoming neutron energies up to 500 keV, a crucial region…

Nuclear Theory · Physics 2016-09-08 A. Mengoni , T. Otsuka , M. Ishihara

A kaon decaying into three pions is an example of a weak process. However, since the quarks are confined into mesons, the strong interaction also plays an important part. The reaction is a low-energy one, meaning that it takes place in the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Fredrik Borg

Most high-dimensional matrix recovery problems are studied under the assumption that the target matrix has certain intrinsic structures. For image data related matrix recovery problems, approximate low-rankness and smoothness are the two…

Machine Learning · Statistics 2021-04-08 Long Feng , Junhui Wang

A possible mechanism for the formation of heavy-mass elements in supernovae is the rapid neutron-capture-mechanism (r-process). It depends upon the electron-fraction $Y_e$, a quantity which is determined by beta-decay-rates. In this paper,…

Nuclear Theory · Physics 2020-07-07 M. M. Saez , O. Civitarese , M. E. Mosquera

Weak radiative hyperon decays present us with a long-standing puzzle, namely the question of validity of a hadron-level theorem proved by Hara. We briefly discuss the conflict between expectations based on Hara's theorem and experiment as…

High Energy Physics - Phenomenology · Physics 2009-10-28 Piotr Zenczykowski

The nonmesonic weak decay of $\Lambda$ hypernuclei is studied using nuclear matter. We have developed a formalism which gives a microscopic interpretation of the process of emission of particles originated in this decay. More specifically,…

Nuclear Theory · Physics 2015-06-26 E. Bauer

In nuclear astrophysics, the accurate determination of nuclear reaction cross sections at astrophysical energies is critical for understanding stellar evolution and nucleosynthesis. This study focuses on the $^{12}$C($p, \gamma$)$^{13}$N…