English
Related papers

Related papers: Onset of $\eta$ nuclear binding

200 papers

The \eta-meson collision with light nuclei, ^2H, ^3H, ^3He, and ^4He, is considered on the basis of a microscopic approach which utilises Faddeev type and Lippmann-Schwinger equations. The nuclear hamiltonian is approximated by the finite…

Nuclear Theory · Physics 2007-05-23 S. A. Sofianos , S. A. Rakityansky , M. Braun

The existence of etamesic nuclei has been speculated for a long time without firm experimental evidence. Much of the effort has taken place in final state interactions on production. One crucial factor in seeing a quasibound state is its…

Nuclear Theory · Physics 2015-11-30 J. A. Niskanen

Due to its dominance in the low energy eta-nucleon interaction, the S11 N$^*$(1535) resonance enters as an important ingredient in the analyses of experiments aimed at finding evidence for the existence of eta-mesic nuclei. The static…

Nuclear Theory · Physics 2016-11-23 N. G. Kelkar

The possibility of etamesic nuclei remains an open problem in nuclear physics until now. Various calculations give contradictory predictions even for the lightest real nucleus $^3$He. In this paper we present the connection of the binding…

Nuclear Theory · Physics 2015-06-05 Jouni A. Niskanen , Hartmut Machner

We argue that eta bound states in nuclei are sensitive to the singlet component in the eta. The bigger the singlet component, the more attraction and the greater the binding. Thus, measurements of eta bound states will yield new information…

High Energy Physics - Phenomenology · Physics 2010-02-17 Steven D. Bass , Anthony W. Thomas

Possible existence of $(c\bar{c})-$nucleus bound states are examined. We adopt Gaussian potentials for the $\eta_{c}-N$ and $J/\psi-N$ interactions. The relations between the scattering lengths $a$ of $(c\bar{c})-N$ interactions and the…

Nuclear Theory · Physics 2013-11-14 Akira Yokota , Emiko Hiyama , Makoto Oka

The in-medium Eta-N interaction near and below threshold is constructed from a free-space chirally-inspired meson-baryon coupled-channel model that captures the physics of the N(1535) baryon resonance. Nucleon Pauli blocking and hadron…

Nuclear Theory · Physics 2015-06-18 A. Cieplý , E. Friedman , A. Gal , J. Mareš

Binding energies of light, $A\leq 6$, $\Lambda\Lambda$ hypernuclei are calculated using the stochastic variational method in a pionless effective field theory (EFT) approach at leading order with the purpose of assessing critically the…

Nuclear Theory · Physics 2020-12-22 L. Contessi , M. Schäfer , N. Barnea , A. Gal , J. Mareš

In a recent paper by the TAPS collaboration \cite{exp} a first measurement of a bound system of an $\eta$ meson and a ${^3}$He nucleus was reported. In this comment we critically reexamine the interpretation of the data and show that the…

High Energy Physics - Phenomenology · Physics 2008-11-26 C. Hanhart

In May-June 2014, the experiment devoted to the search for the bound state of the $\eta$ meson and $^3$$He$ nucleus has been performed at COSY accelerator in Research Center J\"ulich in Germany with WASA-at-COSY facility. The excitation…

High Energy Physics - Experiment · Physics 2019-05-22 Oleksandr Rundel

We demonstrate that the binding energies and widths of eta-mesic nuclei depend strongly on subthreshold eta-N interaction. This strong dependence is made evident from comparing three different eta-nucleus optical potentials: (1) a…

Nuclear Theory · Physics 2009-11-07 Q. Haider , L. C. Liu

The cross section and tensor analysing power t_20 of the d\vec{d}->eta 4He reaction have been measured at six c.m. momenta, 10 < p(eta) < 90 MeV/c. The threshold value of t_20 is consistent with 1/\sqrt{2}, which follows from parity…

The in-medium mass of the $\eta^{\prime}$ meson is discussed in a context of partial restoration of chiral symmetry in nuclear medium. The $\eta^{\prime}$ mass is expected to be reduced by order of 100 MeV at the saturation density. The…

Nuclear Theory · Physics 2012-03-22 Daisuke Jido , Hideko Nagahiro , Satoru Hirenzaki

Motivated by the two recent observations in the WASA-at-COSY detector, we investigate the $\eta^3$He nucleus with the $\eta NNN$ few body method. We construct the effective $s$-wave energy dependent $\eta N$ potential which reproduce the…

Nuclear Theory · Physics 2024-02-13 Qian Wu , Gang Xie , Xurong Chen

We discuss weakly bound states of a few-fermion system having spin-isospin symmetry. This corresponds to the nuclear physics case in which the singlet, $a_0$, and triplet, $a_1$, $n-p$ scattering lengths are large with respect to the range…

Nuclear Theory · Physics 2016-04-20 A. Kievsky , M. Gattobigio

A microscopic treatment of $\eta$--nucleus scattering is presented. When applying the underlying exact integral equations, the excitation of the target are neglected, and an input $\eta N$ amplitude is chosen which reproduces the…

Nuclear Theory · Physics 2011-04-15 V. B. Belyaev , S. A. Rakityansky , S. A. Sofianos , M. Braun , W. Sandhas

Using the quark-meson coupling (QMC) model, we investigate whether $\omega, \eta, \eta'$ and $D^-$ mesons form meson-nucleus bound states. Our results suggest that one should expect to find $\eta$- and $\omega$-nucleus bound states in all…

Nuclear Theory · Physics 2009-10-31 K. Tsushima

We present updated and extended results for the $\eta$- and $\eta'$-nucleus bound state energies, obtained by solving the Schr\"{o}dinger and Klein-Gordon equations with complex optical potentials, for a wide range of nuclei. The $\eta$ and…

Nuclear Theory · Physics 2024-02-26 J. J Cobos-Martinez , Kazuo Tsushima

The connection of the binding energy and width of possible bound eta-mesic states is given to the complex scattering length for s-states in the hope that, with knowledge of the final state interaction this could be useful in searches of…

Nuclear Theory · Physics 2015-06-18 J. A. Niskanen

The mass of the {\eta}' meson is theoretically expected to be reduced at finite density, which indicates the existence of {\eta}'-nucleus bound states. To investigate these states, we perform missing-mass spectroscopy for the (p, d)…