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Related papers: Testing in-medium $\pi N$ dynamics on pionic atoms

200 papers

Exploiting $B$-meson decays for Standard Model tests and beyond requires a precise understanding of the strong final-state interactions that can be provided model-independently by means of dispersion theory. This formalism allows one to…

High Energy Physics - Phenomenology · Physics 2016-02-17 J. T. Daub , C. Hanhart , B. Kubis

This paper is devoted to the interplay between p-wave, s-wave pion-nucleon/ nucleus interaction and in-medium pion-pion interaction with special emphasis on the role of the nuclear pionic scalar density driving a large amount of chiral…

Nuclear Theory · Physics 2007-05-23 Guy Chanfray , Dany Davesne

A new analysis of S-wave production amplitudes for the reaction $\pi^- p_{\uparrow} \rightarrow \pi^+ \pi^- n$ on a transversely polarized target is performed. It is based on the results obtained by the CERN-Cracow -Munich collaboration in…

High Energy Physics - Phenomenology · Physics 2008-11-26 R. Kaminski , L. Lesniak , K. Rybicki

There have been suggestions to measure atomic parity nonconservation (PNC) along an isotopic chain, by taking ratios of observables in order to cancel complicated atomic structure effects. Precise atomic PNC measurements could make a…

Nuclear Theory · Physics 2008-11-26 S. J. Pollock , E. N. Fortson , L. Wilets

A microscopic model for the $N\bar N\to\pi\pi$ process is presented in the meson exchange framework, which in the pseudophysical region agrees with available quasiempirical information. The scalar ($\sigma$) and vector ($\rho$) piece of…

Nuclear Theory · Physics 2009-09-25 C. Schütz , J. W. Durso , K. Holinde , B. C. Pearce , J. Speth

Optical potentials for $K^+$-nucleus interactions are constructed from $K^+$-nucleon amplitudes using recently developed algorithm based on $K^+$-N kinematics in the nuclear medium. With the deep penetration of $K^+$ mesons into the nucleus…

Nuclear Theory · Physics 2016-07-27 E. Friedman

A novel comparison between the data and the theory is proposed for the nonmesonic (NM) weak decay of hypernuclei. Instead of confronting the primary decay rates, as is usually done, we focus attention on the effective decay rates that are…

Nuclear Theory · Physics 2015-03-10 Franjo Krmpotic , Cláudio De Conti

The coherent pion production induced by neutrinos in nuclei is studied using a delta hole model in local density approximation taking into account the renormalization of $\Delta$ properties in a nuclear medium. The pion absorption effects…

Nuclear Theory · Physics 2009-11-11 S. K. Singh , M. Sajjad Athar , Shakeb Ahmad

Proton-nucleus collisions, where the beam proton gets excited to the delta resonance and then decays to p$\pi ^+$, either inside or outside the nuclear medium, are studied. Cross-sections for various kinematics for the (p,p$' \pi ^+$)…

Nuclear Theory · Physics 2009-09-25 B. K. Jain , Bijoy Kundu

In this paper a short review of the theoretical problems of the pionic radioactivity as a new nuclear mode is presented. The essential theoretical and experimental results obtained in the 25 years from the prediction of the nuclear pionic…

Nuclear Theory · Physics 2011-01-25 D. B. Ion , M. L. D. Ion , Reveica Ion-Mihai

We study the in-medium properties of mesons $(\pi,\eta,\rho)$ and baryon resonances in cold nuclear matter within a coupled-channel analysis. The meson self energies are generated by particle-hole excitations. Thus multi-peak spectra are…

Nuclear Theory · Physics 2009-11-10 M. Post , S. Leupold , U. Mosel

For the first time, elastic pion-nucleon scattering is analyzed in the framework of chiral perturbation theory up to fourth order with explicit $\Delta$ degrees of freedom. The analysis is performed within the heavy-baryon expansion as well…

Nuclear Theory · Physics 2020-01-15 Dmitrij Siemens

We apply the nuclear model with explicit mesons to photoproduction of neutral pions off protons at the threshold. In this model the nucleons do not interact with each other via a potential but rather emit and absorb mesons that are treated…

Nuclear Theory · Physics 2022-12-15 D. V. Fedorov , M. Mikkelsen

The pion production reaction $\pi^+ \to \pi^+\pi^{\pm}$ on $^{45}Sc$ was studied at incident pion energies of $T_{\pi^{+}}$ = 240, 260, 280, 300, and 320 MeV. The experiment was performed using the $M11$ pion-channel at TRIUMF, and…

The s-wave isoscalar amplitude for pion-pion scattering in a nuclear medium is evaluated using a nonperturbative unitary coupled channels method and the standard chiral Lagrangians. The method has proved successful to describe the pion-pion…

Nuclear Theory · Physics 2008-11-26 H. C. Chiang , E. Oset , M. J. Vicente Vacas

Mechanism of di-pion transitions $nS\to n'S\pi\pi(n=3,2; n'=2,1)$ in bottomonium and charmonium is studied with the use of the chiral string-breaking Lagrangian allowing for the emission of any number of $\pi(K,\eta),$ and not containing…

High Energy Physics - Phenomenology · Physics 2008-11-26 Yu. A. Simonov

The high-density behavior of nuclear symmetry energy is among the most uncertain properties of dense neutron-rich matter. Its accurate determination has significant ramifications in understanding not only the reaction dynamics of heavy-ion…

Nuclear Theory · Physics 2014-02-27 Zhi-Gang Xiao , Gao-Chan Yong , Lie-Wen Chen , Bao-An Li , Ming Zhang , Guo-Qing Xiao , Nu Xu

Nonmesonic decays of $\Lambda$ in nuclear medium and light hypernuclei are studied by using the $\Lambda N \to NN$ weak transition potential derived from the meson exchange mechanism and the direct quark mechanism. The long range part of…

Nuclear Theory · Physics 2017-08-23 Makoto Oka , Kenji Sasaki , Takashi Inoue

Over twenty-five years ago, two analyses of the pion-nucleon ($\pi N$) data at low energy (i.e., for pion laboratory kinetic energy $T \leq 100$ MeV) reported on the departure of the extracted scattering amplitudes, corresponding to the two…

Nuclear Theory · Physics 2022-06-07 Evangelos Matsinos

The results of an extensive campaign of measurements of the pi -> pi pi process in the nucleon and nuclei at intermediate energies are presented. The measurements were motivated by the study of strong pi pi correlations in nuclei. The…