Search results for "Faddeev equations"
showing 10 items of 36 documents
Chiral unitary approach to the K^- deuteron scattering length
2000
Starting from a recent model where the Kbar N amplitudes are evaluated from the chiral Lagrangians using a coupled channel unitary method, we evaluate here the scattering length for K^- deuteron scattering. We find that the double scattering contribution is very large compared to the impulse approximation and that the charge exchange contribution of this rescattering is as large as the sequential K^- scattering on the two nucleons. Higher order rescattering corrections are evaluated using coupled channels with K^- and Kbar^0 within the integral form of the fixed centre approximation to the Faddeev equations. The higher order corrections involving intermediate pions and hyperons are found ne…
Solution to Faddeev equations with two-body experimental amplitudes as input and application toJP=1/2+,S=0baryon resonances
2009
We solve the Faddeev equations for the two meson-one baryon system $\ensuremath{\pi}\ensuremath{\pi}N$ and coupled channels using the experimental two-body $t$ matrices for the $\ensuremath{\pi}N$ interaction as input and unitary chiral dynamics to describe the interaction between the rest of coupled channels. In addition to the ${N}^{*}(1710)$ obtained before with the $\ensuremath{\pi}\ensuremath{\pi}N$ channel, we obtain, for ${J}^{\ensuremath{\pi}}=1/{2}^{+}$ and total isospin of the three-body system $I=1/2$, a resonance peak whose mass is around 2080 MeV and width 54 MeV, while for $I=3/2$ we find a peak around 2126 with 42 MeV of width. These two resonances can be identified with the …
X(2175)as a resonant state of theϕKK¯system
2008
We perform a Faddeev calculation for the three-meson system $\ensuremath{\phi}K\overline{K}$, taking the interaction between two pseudoscalar mesons and between a vector and a pseudoscalar meson from the chiral unitary approach. We obtain a neat resonance peak around a total mass of 2150 MeV and an invariant mass for the $K\overline{K}$ system around 970 MeV, very close to the ${f}_{0}(980)$ mass. The state appears in $I=0$ and qualifies as a $\ensuremath{\phi}{f}_{0}(980)$ resonance. We enlarge the space of states including $\ensuremath{\phi}\ensuremath{\pi}\ensuremath{\pi}$, since $\ensuremath{\pi}\ensuremath{\pi}$ and $K\overline{K}$ build up the ${f}_{0}(980)$, and find moderate changes…
States Of Rho D*(D)Over-Bar* With J=3 Within The Fixed Center Approximation To The Faddeev Equations
2015
We study the interaction of ρ, D * and $$\bar D^*$$ with spins aligned using the fixed center approximation to the Faddeev equations. We select a cluster of $$D^* \bar D^*$$ , which is found to be bound in I = 0 and can be associated to the X(3915), and let the ρ meson orbit around the D * and $$\bar D^*$$ . In this case we find an I = 1 state with mass around 4340 MeV and narrow width of about 50 MeV. We also investigate the case with a cluster of ρD * and let the $$\bar D^*$$ orbit around the system of the two states. The ρD * cluster is also found to bind and leads to the D 2 * state. The addition of the extra $$\bar D^*$$ produces further binding and we find, with admitted uncertainties…
Three-body hadronic molecules
2010
In this talk, I discuss our recent studies of three-hadron systems and the resonances found therein. The studies consist of solving Faddeev equations with the input two body interactions obtained from the chiral Lagrangians. The systems which we study are either made of two mesons and a baryon or of three mesons. The motivation for these studies comes from the data on many baryon resonances, especially the ones with Jπ = 1/2+, which show a large branching ratio to the two meson-one baryon decay channels. In addition to this, several new studies at BES, BELLE, BABAR etc., claim the existence of new meson resonances which seem to couple strongly to three-meson systems, where mostly two out of…
Electromagnetic Production of the Hypertriton
1996
Kaon photoproduction on He3, gamma + He3 --> K+ + Hypertriton, is studied in the framework of the impulse approximation. Realistic He3 wave functions obtained as solutions of Faddeev equations with the Reid soft-core potential are used along with different Hypertriton wave functions. Results are compared for several elementary operator models, which can successfully describe the elementary kaon production off the proton up to a photon lab energy of k = 2.2 GeV. It is found that the corresponding cross sections are small, of the order of several nanobarns. It is also shown that the influence of Fermi motion is important, while the effect of different off-shell assumptions on the cross sec…
The N*(1710) as a resonance in the ππN system
2008
We study the $\pi \pi N$ system by solving the Faddeev equations, for which the input two-body $t$-matrices are obtained by solving the Bethe-Salpeter equation in the coupled channel formalism. The potentials for the $\pi \pi$, $\pi N$ sub-systems and their coupled channels are obtained from chiral Lagrangians, which have been earlier used to study resonances in these systems successfully. In this work, we find a resonance in the $\pi\pi N$ system with a mass of $1704 - i 375/2$ MeV and with quantum numbers $I=1/2$, $J^\pi =1/2^+$. We identify this state with the $N^*(1710)$. This peak is found where the energies of the $\pi \pi$ sub-system fall in the region of the $\sigma$ resonance. We d…
Plausible explanation for theΔ5/2+(2000)puzzle
2011
From a Faddeev calculation for the $\ensuremath{\pi}$-$(\ensuremath{\Delta}\ensuremath{\rho}){}_{{N}_{5/{2}^{\ensuremath{-}}}(1675)}$ system we show the plausible existence of three dynamically generated $I({J}^{P})=3/2(5/{2}^{+})$ baryon states below 2.3 GeV, whereas only two resonances, ${\ensuremath{\Delta}}_{5/{2}^{+}}(1905)(****)$ and ${\ensuremath{\Delta}}_{5/{2}^{+}}(2000)(**),$ are cataloged in the Particle Data Book Review. Our results give theoretical support to data analyses extracting two distinctive resonances, ${\ensuremath{\Delta}}_{5/{2}^{+}}(~$1740) and ${\ensuremath{\Delta}}_{5/{2}^{+}}(~$2200), from which the mass of ${\ensuremath{\Delta}}_{5/{2}^{+}}(2000)(**)$ is estima…
Three-body resonances in two-meson-one-baryon systems
2007
We report four $\Sigma$'s and three $\Lambda$'s, in the 1500 - 1800 MeV region, as two meson - one baryon S-wave $(1/2)^+$ resonances. We solve Faddeev equations in the coupled channel approach. The invariant mass of one of the meson-baryon pairs and that of the three particles have been varied and peaks in the squared three body $T$-matrix have been found very close to the existing $S$ = -1, $J^P= 1/2^+$ low lying baryon resonances. The input two-body $t$-matrices for meson-meson and meson-baryon interaction have been calculated by solving the Bethe-Salpeter equation with the potentials obtained in the chiral unitary approach.
States of $ \rho$ B* $ \bar{{B}}^{{*}}_{}$ with J = 3 within the fixed center approximation to Faddeev equations
2015
We study the interaction of the a $\rho$ and $D^*$, $\bar D^*$ with spins aligned using the Fixed Center Approximation to the Faddeev equations. We select a cluster of $D^* \bar D^*$, which is found to be bound in $I=0$ and can be associated to the X(3915), and let the $\rho$ meson orbit around the $D^*$ and $\bar D^*$. In this case we find an $I=1$ state with mass around 4340 MeV and narrow width of about 50 MeV. We also investigate the case with a cluster of $\rho D^*$ and let the $\bar D^*$ orbit around the system of the two states. The $\rho D^*$ cluster is also found to bind and leads to the $D^*_2(2460)$ state. The addition of the extra $\bar D^*$ produces further binding and we find,…