We study the transition from the initial
state to the
final state in the mass region near the mass of the
state. To extract this contribution we perform the combined analysis of the data obtained ...with a neutron beam and a hydrogen target and the data from the
reaction.
The mixing angles between scalar isoscalar resonances and a scalar glueball are determined from their decays into two pseudoscalar mesons. For f0(1370) and f0(1500), at most a small glueball ...component is admitted by the data. The decay modes of f0(1710), f0(1770), f0(2020), and f0(2100) require significant glueball fractions. Above this mass, the errors in the decay frequencies become too large to extract a glueball component. The summation of all observed glueball fractions up to 2100MeV yields (78±18)%. The glueball fractions as function of the mass are consistent with a scalar glueball at 1865MeV and a width of 370MeV as suggested by a measurement of the yield of scalar isoscalar mesons in radiative J/ψ decays.
Differential cross sections obtained for the reaction
at five incident proton momenta of 1345, 1393, 1439, 1486, and 1536 MeV/
c
are presented. The respective measurements were performed with the aid ...of a hydrogen-filled bubble chamber. The angular and mass distributions in two-particle channels are compared with the predictions of the one-pion-exchange model and are subjected to a partial-wave analysis with the aim of determining the contributions of various partial waves to the process of pion production in the energy region being studied.
The differential spectra of final particles in the reaction
are presented according to data obtained at nine energy values with the aid of a deuterium-filled bubble chamber. These spectra are ...compared with the results of a partial-wave analysis of data obtained with a continuous neutron beam incident to a proton target. This analysis was used as basis for performing a global partial-wave analysis of data on proton–neutron, neutron–proton, and proton–proton collisions. As a result, it became possible to determine the contributions of both isovector and isoscalar partial waves to a precision substantially higher than that reached earlier.
Data on the reaction γp→K^{+}Λ from the CLAS experiments are used to derive the leading multipoles, E_{0+}, M_{1-}, E_{1+}, and M_{1+}, from the production threshold to 2180 MeV in 24 slices of the ...invariant mass. The four multipoles are determined without any constraints. The multipoles are fitted using a multichannel L+P model that allows us to search for singularities and to extract the positions of poles on the complex energy plane in an almost model-independent method. The multipoles are also used as additional constraints in an energy-dependent analysis of a large body of pion and photoinduced reactions within the Bonn-Gatchina partial wave analysis. The study confirms the existence of poles due to nucleon resonances with spin parity J^{P}=1/2^{-}, 1/2^{+}, and 3/2^{+} in the region at about 1.9 GeV.
A coupled-channel analysis of BESIII data on radiative J/ψ decays into ππ, KK¯, ηη and ωϕ has been performed. The partial-wave amplitude is constrained by a large number of further data. The analysis ...finds ten isoscalar scalar mesons. Their masses, widths and decay modes are determined. The scalar mesons are interpreted as mainly SU(3)-singlet and mainly octet states. Octet isoscalar scalar states are observed with significant yields only in the 1500-2100MeV mass region. Singlet scalar mesons are produced over a wide mass range but their yield peaks in the same mass region. The peak is interpreted as scalar glueball. Its mass and width are determined to M=1865±25−30+10MeV and Γ=370±50−20+30MeV, its yield in radiative J/ψ decays to (5.8±1.0)10−3.
Proton-η′ interactions at threshold Anisovich, A.V.; Burkert, V.; Dugger, M. ...
Physics letters. B,
10/2018, Letnik:
785, Številka:
C
Journal Article
Recenzirano
Odprti dostop
Recent data on photoproduction of η′ mesons off protons have been included in the data base for the Bonn–Gatchina partial wave analysis. The real and imaginary parts of the S-wave η′p→η′p scattering ...amplitude in the threshold region were fit to yield the η′p scattering length and the interaction range. This new analysis found |aη′p|=(0.403±0.015±0.060) fm and a phase ϕ=(87±2)∘, while the range parameter is not well-constrained. The striking behavior of the GRAAL data on the beam asymmetry in the threshold region suggests that a narrow proton-η′ resonance might exist. However, the scattering length was found to be relatively insensitive to the possible existence of this narrow resonance.
The antiquark-diquark-diquark model describes pentaquark states both in terms of quarks and hadrons. We discuss pentaquark states with hidden charm
P
(
c
¯
c
u
u
d
)
discovered in the
J
/
Ψ
p
...spectrum by the LHCb collaboration. We consider three pentaquark states as members of the lowest (
S
-wave) multiplet and discuss the mass splitting scheme. The latest LHCb data for pentaquarks with hidden charm provide an opportunity to make an assumption about the diquark content of the pentaquark states. We give a classification for the LHCb pentaquarks and define recombination channels for these states.
Properties of nucleon and
Δ
resonances are derived from a multichannel partial wave analysis of pion and photo-induced reactions off protons. This paper summarizes the latest results on masses, ...widths, and decay properties of nucleon and
Δ
resonances.
Search for the tensor glueball Klempt, E.; Nikonov, K.V.; Sarantsev, A.V. ...
Physics letters. B,
07/2022, Letnik:
830
Journal Article
Recenzirano
Odprti dostop
The tensor glueball is searched for in BESIII data on radiative J/ψ decays into π0π0 and KsKs. The ππ invariant mass distribution exhibits an enhancement that can be described by a pole at ...(2210±60)−i(180±60)MeV or by three of ϕϕ resonances suggested a long time ago to be the trace of one, two or three glueballs. We speculate that several high-mass tensor mesons might have qq¯ and glueball components.
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