We determine the ratio of the partial decay width for ψ(3684)→μ+μ− to that for the cascade decay ψ(3684)→ψ(3095)+X to be (1.4 ± 0.3)% and, by direct observation of associated charged particles and γ rays, find the ratio of the partial decay width for ψ(3684)→ψ(3095)+π0π0 to that for ψ(3684)→ψ(3095)+π+π− to be 0.64 ± 0.15.
Axis error includes +- 20/20 contribution (UNKNOWN SYSTEMATICAL ERRORDECAY-BR(BRN=J/PSI(3097) --> MU+ MU-, BR=?, C=FOLDED)).
Axis error includes +- 20/20 contribution (UNKNOWN SYSTEMATICAL ERRORDECAY-BR(BRN=J/PSI(3097) --> MU+ MU-, BR=?, C=FOLDED)).
The reactions e + e − → ρη , ρπ , φπ and φη have been studied with the magnetic detector DM1 at DCI in the total energy ranges between 1.4 and 2.18 GeV. The ρη signal is clearly seen. Upper limits for ρπ and φη channels as well as for the OZI forbidden φπ channel.
No description provided.
UPPER LIMIT TO SIG AS EXPLAINED IN SYSTEMATICS.
UPPER LIMIT TO CROSS SECTION AT CL=90 PCT.
The total cross section of the pp→ pp η reaction has been measured at incident proton energies of 1.265, 1.3, 1.4 and 1.5 GeV by detecting the two photons from the η decay in the PINOT spectrometer. The data are compared with other near-threshold measurements and with the predictions of existing theoretical calculations.
Value given at 1263 MeV assumes energy 2 MeV lower than nominal value. This uncertainty only affects this lowest energy point.
The total electromagnetic cross sections of g-rays in hydrogen and deuterium have been measured over the energy range 265–4215 MeV using a photon tagging system. From these measurements, the total pair production cross sections are obtained, and the results are found to be in good agreement with the predictions of Jost, Luttinger and Slotnick.
Axis error includes +- 1/1 contribution.
We give new experimental results on ρω interference and two-body cross sections in p¯p annihilation at 2.3GeVc. These are used, together with ρω interference results from lower energies, to argue that the annihilation process is not mediated by discrete s-channel mesonic resonances in the mass range 2.1-2.6 GeV.
No description provided.
We report on a measurement for the branching-ratio X 0 → 2γ X 0 ar all. Our result is X 0 → 2γ X 0 → all = (2.9 ± 0.9)% .
BY COMPARISON WITH THE KNOWN ETA PRODUCTION CROSS SECTION.
Qausi-elastic ω production by ep scattering in the kinematic region 0.3. < Q 2 < 1.4 GeV 2 and 1.7 < W < 2.8 GeV was studied using a streamer chamber at DESY. The production angular distribution for γ V p → ω p has a strong non-peripheral component for W < 2 GeV. The ω production cross section falls by a factor of 4 as W changes from 1.7 to 2.8 GeV. In contrast the cross section for ω production with | t | < 0.5 GeV 2 is W independent between 1.7 and 2.8 GeV and for W > 2.0 GeV consistent in both W and Q 2 dependence with the predictions of a model based on one-pion exchange and diffraction.
FOR ALL T-VALUES. THE GAMMA* P TOTAL CROSS SECTION WAS TAKEN FROM A FIT TO THE DATA OF S. STEIN ET AL., PR D12, 1884 (1975). 'PPD'.
'PPD'. PERIPHERAL OMEGA PRODUCTION.
No description provided.
Final states ηΛ and η ′ Λ were studied in K − p interactions at 3.95 GeV c . Cross sections, angular distributions and Λ polarizations are reported. The coupling ration R T = (η 1 K K ∗∗ (1420) (η 8 K K ∗∗ (1420)) M is found to be independent of the momentum transfer. Backward Λη is compared to K − p → Λπ o , π ± p → pπ ± and π − p → nπ o at the same momentum.
No description provided.
No description provided.
No description provided.
Electroproduction of exclusive $\phi$ vector mesons has been studied with the CLAS detector in the kinematical range $1.6\leq Q^2\leq 3.8$ GeV$^{2}$, $0.0\leq t^{\prime}\leq 3.6$ GeV$^{2}$, and $2.0\leq W\leq 3.0$ GeV. The scaling exponent for the total cross section as $1/(Q^2+M_{\phi}^2)^n$ was determined to be $n=2.49\pm 0.33$. The slope of the four-momentum transfer $t'$ distribution is $b_{\phi}=0.98 \pm 0.17$ GeV$^{-2}$. The data are consistent with the assumption of s-channel helicity conservation (SCHC). Under this assumption, we determine the ratio of longitudinal to transverse cross sections to be $R=0.86 \pm 0.24$. A 2-gluon exchange model is able to reproduce the main features of the data.
Axis error includes +- 18.6/18.6 contribution.
Axis error includes +- 18.6/18.6 contribution.
Axis error includes +- 18.6/18.6 contribution.
We describe a search for psi(3770) decay to two-body non-DDbar final states in e+e- data produced by the CESR collider and analyzed with the CLEO-c detector. Vector-pseudoscalar production of Rho0Pi0, Rho+Pi-, OmegaPi0, PhiPi0, RhoEta, OmegaEta, PhiEta, RhoEtaPrime, OmegaEtaPrime, PhiEtaPrime, Kstar0 K0bar, and Kstar+K- is studied along with that of BOnePi (BOne0Pi0 and BOne+Pi-) and Pi+Pi-Pi0. A statistically significant signal is found for PhiEta, at an excess cross section of (2.4 +- 0.6) pb [Gamma_{PhiEta} (psi(3770)) =(74 +- 16)Mev], and a suggestive suppression of Pi+Pi-Pi0 and RhoPi. We conclude with form factor determinations for OmegaPi0, RhoEta, and RhoEtaPrime.
Cross sections at 3.671 and 3.773 GeV.