The results of the first experiment performed at DCI in e + e − annihilations in the c.m. energy range 1.350–2.125 GeV region are presented. The cross sections of various multipion channels are extracted. Significant structure appears in some specific channels. A relatively narrow resonance around 1.660 GeV decaying into 3 π 's is found. Charged and neutral multiplicities, and also the ratio R are given.
PEAK CROSS SECTION FROM FIT WITH BREIT-WIGNER RESONANCE PLUS CONSTANT BACKGROUND TO ISOSCALAR JPC = 1-- STRUCTURE OF MASS 1652 +- 17 MEV AND WIDTH OF 42 +- 17 MEV.
R VALUE SEEMS CONSTANT OVER THIS ENERGY RANGE.
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THE TOTAL CROSS SECTION HAS BEEN CALCULATED FROM R.
From a muon-proton scattering experiment with a streamer chamber at the Stanford Linear Accelerator we present results in the ranges 0.3
THE ABSOLUTE TOTAL CROSS SECTION IS FROM A FIT TO THE MIT-SLAC ELECTRON SCATTERING DATA BY W. ATWOOD AND S. STEIN.
No description provided.
FOR 0.6 < M(PI+ PI-) < 0.9 GEV, USING THE METHOD OF MOMENTS.
An analysis of the K 0 K 0 system at threshold produced in the final states p p → K S 0 K S 0 ( n π) at 700–760 MeV/ c , is presented. A simultaneous fit to the ππ phase shifts and inelasticities and to the K S 0 K S 0 effective-mass distributions using parametrizations which take into account the analytical and unitarity properties of the I = 0 S-wave amplitudes is performed. The behaviour of the eigenphases and the unphysical Riemann sheet structure for different solutions is studied.
No description provided.
FIT TO RESONANCE PRODUCTION CHANNELS IN <KS KS PI+ PI-> FINAL STATE.
FIT TO RESONANCE PRODUCTION CHANNELS IN <KS KS PI0> FINAL STATE.
In this paper we have investigated the properties of the D(1285) and E(1420) meson resonances using the five-body annihilation channels p p → K K πππ obtained in a large statistics experiment (28 events/μb). The analysis favours the 1 + spin-parity assignment for the D(1285) meson. The dominant decay mode of the D(1285) into K K π is found to be δ(970)π. The situation concerning the E(1420) meson remains confused although not inconsistent with previous analyses. Partial cross sections on resonance production are also presented.
No description provided.
The cross section ratio of the elastic neutral current reaction ν p→ ν p to the quasi-elastic charged current reaction ν n→ μ − p has been measured in the kinematical region 0.3⩽ q 2 ⩽1.0 (GeV/ c ) 2 . The measured value is R M =0.17±0.08. Model dependent corrections are applied, especially for ν n→ ν n contamination, and the result is compared to various models.
(C=OBSERVED) and (C=CORRECTED) are the observed and corrected for the nuclear effects ratios.
None
No description provided.
No description provided.
No description provided.
We present experimental evidence for a resonant behaviour of the hadron production from e + e − annihilations at the e + e − storage ring ADONE. A Breit-Wigner fit to the enhancement present between 1800 and 1850 MeV gives the following parameters M = 1812 −13 +7 MeV, Γ = 34 −15 +21 MeV.
MULTIHADRON EVENTS (AT LEAST THREE CHARGED TRACKS) PER UNIT LUMINOSITY.
Multihadron production has been measured at the Adone e + e − storage ring in the c.m. energy region 1600 ÷ 1900 MeV. A resonant behaviour is observed, centered at 1819 ± 5 (±2) MeV, with a width of 24 ± 5 (±4) MeV. This effect is observed only in the events with 3 or 4 charged particles together with photons, but not in those without photons.
MULTIHADRON EVENTS (3 OR 4 CHARGED PARTICLES PLUS ONE OR MORE PHOTONS DETECTED) PER UNIT LUMINOSITY. RESONANCE NOT SEEN IN EVENTS WITH NO PHOTONS.
We have measured the production cross section for K s 0 in e + e − annihilation from 3.6 to 5.0 GeV center of mass energy. A substantial increase of the K s 0 yield is observed around 4 GeV in qualitative agreement with the charm hypothesis.
THE DATA GIVEN HERE AT 9.3 GEV AND ABOVE ARE REPORTED IN C. BERGER ET AL., PL 104B, 79 (1981). THE 12.0 AND 30 GEV DATA WERE TAKEN AT PETRA.
No description provided.
No description provided.
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