EXTRACTION OF THE Λ(1405) POLES FROM π0Σ0 PHOTOPRODUCTION DATA

2014 ◽  
Vol 26 ◽  
pp. 1460086
Author(s):  
L. ROCA ◽  
E. OSET
Keyword(s):  
Scattering Amplitudes ◽  
Linear Combination ◽  
Photonuclear Reaction ◽  
Jefferson Lab ◽  
Coupled Channels ◽  
Unitary Approach ◽  
Chiral Unitary Approach ◽  
Free Parameters ◽  
Photoproduction Data

In this contribution we review a work where we showed how to extract the position of the two Λ(1405) poles from experimental photoproduction data which have been measured recently in the γp → K+π0Σ0 reaction at Jefferson Lab. Using a potential motivated by chiral dynamics but with free parameters, we solve the Bethe Salpeter equation in the coupled channels [Formula: see text] and πΣ in isospin I=0 and parameterize the amplitude for the photonuclear reaction in terms of a linear combination of the πΣ → πΣ and [Formula: see text] scattering amplitudes in I=0, with a different linear combination for each energy. Good fits to the data are obtained which lead to two poles at 1385 - 68i MeV and 1419 - 22i MeV, similar to those found in the chiral unitary approach.

scholarly journals Role of scalar $$a_0(980)$$ in the single Cabibbo suppressed process $$D^+ \rightarrow \pi ^{+} \pi ^{0} \eta $$

2020 ◽  
Vol 80 (11) ◽  
Author(s):  
Man-Yu Duan ◽  
Jun-Ya Wang ◽  
Guan-Ying Wang ◽  
En Wang ◽  
De-Min Li
Keyword(s):  
Invariant Mass ◽  
Mass Distributions ◽  
Unitary Approach ◽  
Chiral Unitary Approach ◽  
Free Parameters ◽  
Cabibbo Suppressed ◽  
Dalitz Plots

AbstractTaking into account that the scalar $$a_0(980)$$ a 0 ( 980 ) can be dynamically generated from the pseudoscalar-pseudoscalar interaction within the chiral unitary approach, we have studied the single Cabibbo suppressed process $$D^+\rightarrow \pi ^+\pi ^0\eta $$ D + → π + π 0 η . We find clear peaks of $$a_0(980)^+$$ a 0 ( 980 ) + and $$a_0(980)^0$$ a 0 ( 980 ) 0 in the $$\pi ^+\eta $$ π + η and $$\pi ^0\eta $$ π 0 η invariant mass distributions, respectively. The predicted Dalitz plots of $$D^+\rightarrow \pi ^+\pi ^0\eta $$ D + → π + π 0 η also manifest the significant signals for $$a_0(980)^+$$ a 0 ( 980 ) + and $$a_0(980)^0$$ a 0 ( 980 ) 0 states. The uncertainties of the results due to the free parameters are also discussed. Our study shows that the process $$D^+\rightarrow \pi ^+\pi ^0\eta $$ D + → π + π 0 η can be used to explore the nature of the scalar $$a_0(980)$$ a 0 ( 980 ) , thus we encourage the experimental physicists to measure this reaction with more precision.

scholarly journals CHIRAL UNITARY APPROACH TO HADRON SPECTROSCOPY

2003 ◽  
Vol 18 (03) ◽  
pp. 387-396 ◽  
Author(s):  
E. Oset ◽  
T. Inoue ◽  
M. J. Vicente Vacas ◽  
A. Ramos ◽  
C. Bennhold
Keyword(s):  
Complex Plane ◽  
Final States ◽  
S Wave ◽  
Baryon Interaction ◽  
Hadron Spectroscopy ◽  
Dynamical Generation ◽  
Coupled Channels ◽  
Unitary Approach ◽  
Chiral Unitary Approach ◽  
Chiral Lagrangian

The s-wave meson-baryon interaction in the S = -1, S = 0 and S = -2 sectors is studied by means of coupled channels, using the lowest-order chiral Lagrangian and the N/D method or equivalently the Bethe-Salpeter equation to implement unitarity. This chiral approach leads to the dynamical generation of the Λ(1405), Λ(1670) and Σ(1620) states for S = -1, the N*(1535) for S = 0 and the Ξ(1620) for S = -2. We look for poles in the complex plane and extract the couplings of the resonances to the different final states. This allows identifying the Λ(1405) and the Λ(1670) resonances with [Formula: see text] and K Ξ quasibound states, respectively. Our results are found to be incompatible with the measured properties of the Ξ(1690) resonance, thus ruling this state out as the remaining member of this octet of dynamically generated resonances. We therefore assign 1/2- for the spin and parity of the Ξ(1620) resonance as the S = -2 member of the lowest-lying 1/2- octet.

scholarly journals Study the $$B^{0}_{(s)}$$ decays into $$\phi $$ and a scalar or vector meson

2021 ◽  
Vol 81 (8) ◽  
Author(s):  
Hiwa A. Ahmed ◽  
Zhong-Yu Wang ◽  
Zhi-Feng Sun ◽  
C. W. Xiao
Keyword(s):  
Invariant Mass ◽  
Final State Interaction ◽  
Branching Ratios ◽  
State Interaction ◽  
Final State ◽  
Decay Channels ◽  
Mass Distributions ◽  
Coupled Channels ◽  
Unitary Approach ◽  
Chiral Unitary Approach

AbstractIn the present work, we investigate the decays of $$B^{0}_{(s)} \rightarrow \phi \pi ^{+}\pi ^{-}$$ B ( s ) 0 → ϕ π + π - with the final state interaction based on the chiral unitary approach. In the final state interaction of the $$\pi ^+\pi ^-$$ π + π - with its coupled channels, we study the effects of the $$\eta \eta $$ η η channel in the two-body interaction for the reproduction of the $$f_{0}(980)$$ f 0 ( 980 ) state, where its contribution to the $$f_{0}(980)$$ f 0 ( 980 ) state can be ignored. Our results for the $$\pi ^+\pi ^-$$ π + π - invariant mass distributions of the decay $$B^{0}_{s} \rightarrow \phi \pi ^{+}\pi ^{-}$$ B s 0 → ϕ π + π - describe the experimental data up to 1 GeV well, with the resonance contributions from the $$f_{0}(980)$$ f 0 ( 980 ) and $$\rho $$ ρ . For the predicted invariant mass distributions of the $$B^{0} \rightarrow \phi \pi ^{+}\pi ^{-}$$ B 0 → ϕ π + π - decay, we find that the contributions from the $$f_{0}(500)$$ f 0 ( 500 ) are significant, but not from the $$f_{0}(980)$$ f 0 ( 980 ) state. With some experimental branching ratios to determine the production vertex factors, we make predictions for the branching ratios of the other decay channels, including the vector mesons, in the $$B^0_{(s)}$$ B ( s ) 0 decays, some of which are consistent with the experimental measurements within the uncertainties.

scholarly journals Role of N*(1535) in the Λ+c → K0ηp decay and the possible фp state in the Λ+c → π0фp decay

2020 ◽  
Vol 241 ◽  
pp. 02010
Author(s):  
Ju-Jun Xie ◽  
Li-Sheng Geng ◽  
Feng-Kun Guo
Keyword(s):  
Invariant Mass ◽  
Mass Distribution ◽  
Final State Interaction ◽  
Invariant Mass Distribution ◽  
Lagrangian Model ◽  
Final State ◽  
Peak Structure ◽  
Effective Lagrangian ◽  
Unitary Approach ◽  
Chiral Unitary Approach

The nonleptonic weak decays of Λ+c → K0ηp and Λ+c → π0фp are investigated from the viewpoint of probing the N*(1535) resonance and the possible фp state. For the Λ+c → K0ηp decay, we study the invariant mass distribution of ηp with both the chiral unitary approach and an effective Lagrangian model. Within the chiral unitary approach, the N*(1535) resonance is dynamically generated from the final state interaction of mesons and baryons in coupled channels. While for the effective Lagrangian model, we take a Breit-Wigner formula for the N*(1535) resonance. We found that the behavior of the N*(1535) resonance in the Λ+c → K0N*(1535) → K0ηp decay within the two approaches is different. For the Λ+c → π0фp decay, we consider a triangle singularity mechanism, where the Λ+c decays into the K*Σ*(1385), the Σ*(1385) decays into the π0Σ/Λ, and then the K*Σ/Λ merge to produce the фp in the final state. This mechanism produces a peak structure around 2020 MeV. In addition, the possibility that there is a hidden-strange pentaquark-like state is also considered by taking into account the final state interactions of K*Λ, K*Σ, and фp. We conclude that it is difficult to search for the hidden-strange state in this decay. However, we do expect nontrivial behavior in the фp invariant mass distribution. The proposed Λ+c decay mechanism here can provide valuable information on the properties of these nuclear resonances and can in principle be tested by experiments such as BESIII, LHCb and Belle-II.

THE SCIENCE OF CONFINEMENT AND THE GLUEX/HALL D PROJECT AT JEFFERSON LAB

2003 ◽  
Vol 18 (03) ◽  
pp. 397-404 ◽  
Author(s):  
Alex R. Dzierba
Keyword(s):  
Degrees Of Freedom ◽  
Meson Production ◽  
First Year ◽  
Jefferson Lab ◽  
Coherent Bremsstrahlung ◽  
Linearly Polarized ◽  
Quantitative Understanding ◽  
Current Maximum ◽  
Photo Production ◽  
Photoproduction Data

One of the outstanding and fundamental questions in physics is the quantitative understanding of the confinement of quarks and gluons in quantum chromodynamics (QCD). Confinement is a unique feature of QCD. Exotic hybrid mesons manifest gluonic degrees of freedom and their spectroscopy will provide the crucial data needed to test assumptions in lattice QCD and phenomenology leading to confinement. Photo-production is expected to be particularly effective in producing exotic hybrids but data using photon probes are sparse. At Jefferson Lab, plans are underway to use the coherent bremsstrahlung technique to produce a linearly polarized photon beam. A solenoid-based hermetic detector will be used to collected data on meson production and decays with statistics that will exceed the current photoproduction data in hand by several orders of magnitude after the first year of running. In order to reach the ideal photon energy of 9 GeV/c for this mapping of the exotic spectra, the energy of the Jefferson Lab electron accelerator, CEBAF, will be doubled from its current maximum of 6 GeV to 12 GeV. The physics and project are described.

scholarly journals Dynamically generated 0+ heavy mesons in a heavy chiral unitary approach

2006 ◽  
Vol 641 (3-4) ◽  
pp. 278-285 ◽  
Author(s):  
Feng-Kun Guo ◽  
Peng-Nian Shen ◽  
Huan-Ching Chiang ◽  
Rong-Gang Ping ◽  
Bing-Song Zou
Keyword(s):  
Heavy Mesons ◽  
Unitary Approach ◽  
Chiral Unitary Approach

HADRONIC DECAYS OF η AND η′

2005 ◽  
Vol 20 (02n03) ◽  
pp. 546-548
Author(s):  
B. BORASOY ◽  
N. BEISERT
Keyword(s):  
Hadronic Decays ◽  
S Wave ◽  
Final State ◽  
Effective Lagrangian ◽  
Unitary Approach ◽  
Final State Interactions ◽  
Small Set ◽  
Chiral Unitary Approach ◽  
Spectral Shapes

The hadronic decays η→πππ, η′→πππ and η′→ηππ are investigated within a U(3) chiral unitary approach. Final state interactions are included by deriving the effective s wave potentials for meson meson scattering from the chiral effective Lagrangian and iterating them in a Bethe-Salpeter equation. With only a small set of parameters we are able to explain both rates and spectral shapes of these decays.

Sign in / Sign up

Export Citation Format

Share Document