Nucleon resonances in the fourth-resonance region Anisovich, A. V.; Klempt, E.; Nikonov, V. A. ...
The European physical journal. A, Hadrons and nuclei,
12/2011, Letnik:
47, Številka:
12
Journal Article
Results from a multichannel partial wave analysis of elastic and inelastic πN and γN induced reactions are presented. The analysis evidences the existence of a spin-quartet of nucleon resonances with ...total angular momenta JP=1/2+,…,7/2+. All states fall into a ±130 MeV mass gap centered at 1.97 GeV. The spin quartet is at variance with S-wave diquark configurations required in classical diquark models.
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.
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.
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.
Branching ratios for the decay of hadrons with large width or near thresholds depend on their definition. We test different definitions and show that rather different branching ratios can be ...obtained. For wide resonances and for sequential decays with wide intermediate resonances, integration over the spectral functions is mandatory. The tests are performed exploiting the latest solution of the Bonn-Gatchina multi-channel analysis and published values for residues of light scalar mesons. For a resonance overlapping with a threshold, in case its pole lies in a non-adjacent sheet, we show how the total width, needed for the branching ratios, does not correspond to the imaginary part of the pole position. We use the Madrid-Krakow dispersive parameterizations to illustrate this situation with the f0(980).
Hyperon II: Properties of excited hyperons Sarantsev, A. V.; Matveev, M.; Nikonov, V. A. ...
The European physical journal. A, Hadrons and nuclei,
10/2019, Letnik:
55, Številka:
10
Journal Article
Recenzirano
.
We report properties of
Λ
and
Σ
hyperon resonances formed in
K
-
induced reactions. Special emphasis is laid on the analysis of the three-body final states
2
π
0
Λ
and
2
π
0
Σ
and of the ...quasi-two-body final states
π
Λ
(
1520
)
,
K
¯
Δ
(
1232
)
,
π
Σ
(
1385
)
,
K
¯
*
N
, and
ω
Λ
. We give pole positions of
Λ
and
Σ
hyperon resonances and transition residues from the
K
-
p
initial to various final states as well as Breit-Wigner masses and widths and decay branching ratios. Twenty resonances and “bumps” reported in the Review of Particle Physics are not required in our fits, evidence for five new resonances is reported. The observed mass spectrum is compared to the spectrum calculated in the Bonn quark model. Three spin doublets, six
Λ
hyperons, are tentatively assigned to the
SU
(3) singlet system.
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.