A study is made of η 0 production in p p → 3π + 3π − π 0 (7500 events) at an incident momentum of 720 MeV/ c . The reaction is dominated by production of ω 0 (≈68 o/o). The η o production has been studied by means of two independent methods: the first, a study of correlations between the (4 π ) ± and (5 π ) 0 and the (3 π ) 0 systems, circumvents the problem of ω 0 reflections. The second attempts to isolate the η 0 4π channel by means of rigorous selections using the decay properties of η 0 and ω 0 . The results of the two methods are consistent and confirnm the production of σ +- , D 0 and E 0 with the decays ifD 0 → σ ± π ± → η 0 π + π ( su −), E 0 → σ ± π ∓ → η ( su 0) π + π − , E 0 → η 0 π + π − .
CORRECTED FOR UNOBSERVED ETA DECAYS AND I=0 ASSUMED FOR ETAPRIME, D(1285) AND E(1420) --> ETA PI0 PI0.
The reaction π − p → ηφ has been studied at 1.8 GeV/ c incident pion momentum using the Bologna-CERN NBC set-up, in order to investigate the electromagnetic decay mode φ → ηγ . We observed (27 ± 6) events, yielding a branching ratio Γ(φ → ηγ) Γ(φ → total ) = (7.3 ± 1.9)% . The theoretical implications of this result are discussed.
ASSUMING THE TOTAL PHI CROSS SECTION IS 35 +- 5 MUB, THIS YIELDS THE BRANCHING RATIO OF (7.3 +- 1.9) PCT FOR PHI --> ETA GAMMA.
The reaction pn → pp π − at 7.0 GeV/ c is studied in a pd experiment. Observations on isobar production and low-mass enhancement are reported. The I = 1 2 isobars and the low-mass enhancement produced at the neutron vertex are discussed in terms of the diffraction dissociation plus duality model.
PART OF THE DIFFERENCE BETWEEN DEL PRODUCTION AT THE NEUTRON AND AT THE PROTON VERTICES COULD ARISE FROM DEUTERON EFFECTS.
Measurements of proton-deuteron scattering have been performed using an incident 24.0 GeV/ c proton beam. Momentum-loss spectra of forward-scattered protons were measured by a single-arm spectrometer over a range of proton angles from 13 to 107 mr. The contributions to the proton spectra of single and double scattering can be separated experimentally, thus allowing estimates of proton-neutron elastic cross sections to be deduced from the data over a range of four-momentum transfer squared, |t| 5.8 GeV 2 . Elastic p - d scattering, in which the proton and deuteron were detected in coincidence, has also been measured over a range of | t | from 0.6 to 1.8 GeV 2 .
No description provided.
EXTRACTED FROM SINGLE AND DOUBLE PEAK DEUTERIUM DATA BY THE GLAUBER METHOD WITH FERMI MOTION CORRECTIONS.
We present results on the differential cross sections for the process K + n → K 0 p extracted from the reaction K + d → K 0 pp measured at 13 momenta between 0.64 and 1.51 GeV/ c .
THESE TOTAL CROSS SECTIONS WERE PRESENTED WITH MORE EXPERIMENTAL DETAILS IN G. GIACOMELLI ET AL., NP B37, 577 (1972).
REACTION HAS A SPECTATOR PROTON. THESE ARE NOT FREE NEUTRON CROSS SECTIONS. A 250 MEV/C MOMENTUM CUT IS APPLIED TO THE SPECTATOR MOMENTUM AND D(SIG)/DOMEGA THEN NORMALIZED TO THE UNCUT TOTAL CROSS SECTION FOR K+ DEUT --> K0 P P.
Cross sections are presented for the K + p interacttions with 2, 3, 4 and 5 particles in the final state for incident momenta between 2.1 and 2.7 GeV/c. The results are compared with those from other experiments at nearby momenta.
Axis error includes +- 0.0/0.0 contribution (?////).
We present complete results concerning the five reactions K − p → Λω , K − p → Λφ , K − p → Σ 0 ϱ and K − p → Σ 0 φ . The experimental data are well described by exchange mechanisms and the agreement with the SU(3) symmetry predictions is excellent.
FORWARD AND BACKWARD CROSS SECTIONS ARE FOR COS(THETA) > AND < 0. SLOPE DETERMINED FOR -TP = 0.2 TO 1.0.
AUTHORS ALSO GIVE CORRELATIONS OF LAMBDA POLARIZATION WITH THE MESON POLARIZATION.
No description provided.
We have measured the cross sections for these reactions and the cross sections of resonances produced in them. The production of Y ∗± (1385) , ϱ o (765), and f o (1260) is observed in the first reaction; ϱ o (765) in the second; Y ∗−,o (1385), ω o (748), B − (1235), probably ϱ o,− (765), and an enhancement we interpret to be the J P = 1 2 − Σ o (1750) in the third. Single particle longitudinal momentum distributions and average values of transverse momentum are presented. The observed single particle production angular distributions show good qualitative but not quantitative agreement with the Reggeized multiperipheral model of Chan, Loskiewicz, and Allison. We found strong disagreement between the amounts of observed resonance production and the results of the multiperipheral model of Plahte and Roberts that is based on the models of Chan et al. and Veneziano. However, we included isospin effects only in an approximate manner.
No description provided.
Resonance production in the above reactions containing a proton in the final state is characterized primarily by the production of K ∗− (890). The events with a final state neutron are characterized by the production of either K ∗− (890) or Δ − (1236), but very little double resonance production. Cross sections are presented. Exponential slopes for the momentum-transfer distributions of the K ∗− (890) and Δ − (1236) were determined and found to be much smaller than for elastic scattering. For the π − π − p K 0 events the spin density matrix elements for the decay of the K ∗− (890) in the Jackson frame imply alignment. Single particle longitudinal momentum distributions and average values of transverse momentum are presented. The single particle production angular distributions of all three reactions were compared with the results of the Reggeized multiperipheral model of Chan, Loskiewicz, and Allison (CLA) modified to include resonance production. Good qualitative agreement was found. The data from the π − π − p K 0 events were also compared with a multiperipheral model of Plahte and Roberts that is based on the CLA and Veneziano models.
No description provided.
The non-strange four-prong events of π + p interactions at 3.5 GeV/ c are studied. Cross sections are calculated for all resonance productions in the channels π + p → p π + π + π − ( σ T = 3.18 ± 0.13 mb) and π + p → p π + π + π − π o ( σ T = 4.03 ± 0.16 mb). The dominant two body reactions Δ ++ ϱ o and Δ ++ ω o are investigated in detail, and production and decay distributions are presented as well as joint decay density matrix elements and joint correlation terms. The Δ ++ ϱ o reaction is compared to predictions of OPE with absorption and the Δ ++ ω o is compared to rho-exchange with sharp cutoff.
FOUR-PRONG, NON-STRANGE CROSS SECTIONS. SYSTEMATIC ERROR INCLUDED.
BREIT-WIGNER RESONANCE FITS, ALLOWING FOR PHASE SPACE AND RELEVANT REFLECTIONS, TO <P PI+ PI+ PI-> FINAL STATE.
BREIT-WIGNER RESONANCE FITS, ALLOWING FOR PHASE SPACE AND RELEVANT REFLECTIONS, TO <P PI+ PI+ PI- PI0> FINAL STATE.
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