487 research outputs found
Measurement of the - mixing angle in and beams with GAMS- Setup
The results of mixing angle measurement for , mesons generated
in charge exchange reactions with and beams are preseneted.
When the , mesons are described in nonstrange(NS)--strange(S)
quark basis the and beams allow to study and
parts of the meson wave function. The cross section ratio at
(GeV/c) in the beam is , results in mixing angle . For
beam the ratio is . It was found that
gluonium content in is . The
experiment was carried out with GAMS-4 Setup.Comment: 6 pages, 4 figures, 1 table, to be submitted in European physical
journal C. Minor changes, the Bibliography extende
Study of the system in the mass range up to 1200 MeV
The reaction has been studied with GAMS-2000
spectrometer in the secondary 38 GeV/c -beam of the IHEP U-70
accelerator. Partial wave analysis of the reaction has been performed in the
mass range up to 1200 MeV. The -meson is seen as a sharp
peak in S-wave. The -dependence of production cross section has
been studied. Dominant production of the at a small transfer
momentum confirms the hypothesis of Achasov and Shestakov about significant
contribution of the exchange () in the mechanism
of meson production in -channel of the reaction.Comment: 4 pages, 3 figures, talk given at HADRON'9
Measurement of the decay form factors in the OKA experiment
A precise measurement of the vector and axial-vector form factors difference
in the decay is presented.
About 95K events of are selected in
the OKA experiment. The result is .
Both errors are smaller than in the previous measurements.Comment: 9 pages, 8 figure
On the Surface Structure of Strange Superheavy Nuclei
Bound, strange, neutral superheavy nuclei, stable against strong decay, may
exist. A model effective field theory calculation of the surface energy and
density of such systems is carried out assuming vector meson couplings to
conserved currents and scalar couplings fit to data where it exists. The
non-linear relativistic mean field equations are solved assuming local baryon
sources. The approach is calibrated through a successful calculation of the
known nuclear surface tension.Comment: 12 pages, 9 figure
A study of the etapipi channel produced in central pp interactions at 450 GeV/c
The reaction pp -> pf (eta pi pi) ps has been studied at 450 GeV/c. There is
clear evidence for an a2(1320)pi decay mode of the eta2(1645) and eta2(1870).
In addition, there is evidence for an a0(980)pi$ decay mode of both resonances
and an f2(1270)eta decay mode of the eta2(1870). No evidence is found for a JPC
= 2++ a2(1320)pi wave.Comment: 15 pages, Latex, 4 Figures Branching ratio a2pi /f2 eta correcte
A search for charmonium states produced in central pp interactions at 450 GeV/c
A search for centrally produced charmonium states has been presented. There
is no significant evidence for any charmonium production. An upper limit of 2
nb is found for the cross section of chic production using the decay chic(1P)->
J/psi gamma.Comment: 10 pages, Latex, 4 Figure
A study of the f0(1370), f0(1500), f0(2000) and f2(1950) observed in the centrally produced 4pi final states
The production and decay properties of the f0(1370), f0(1500), f0(2000) and
f2(1950) have been studied in central pp interactions at 450 GeV/c. The dPT,
phi and |t| distributions of these resonances are presented. For the J = 0
states, the f0(1370) and f0(2000) have similar dPT and phi dependences. These
are different to the dPT and phi dependences of the f0(980), f0(1500) and
f0(1710). For the J = 2 states the f2(1950) has different dependences to the
f2(1270) and f2'(1520). This shows that the dPT and phi dependences are not
just J phenomena.Comment: 14 pages, Latex, 4 Figure
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