Results are presented of a wire-spark-chamber spectrometer measurement of the differential cross section for π−p elastic scattering at 14.15 GeV/c. The region covered in the square of the four-momentum transfer, t, is 0.01<−t<0.78 (GeV/c)2. The cross section is found to obey very nearly a simple exponential t dependence with no evidence of structure. A fit to the data of the form dσdt∝exp(bt+ct2) on the range 0.05<−t<0.78 (GeV/c)2 (i.e., above the region affected by Coulomb scattering) yields b=8.26±0.10 (GeV/c)2 and c=1.01±0.17 (GeV/c)−4. Considering the results of previous measurements, b≃11 (GeV/c)−2 for −t<0.05 (GeV/c)2, a deviation from the simple exponential near −t≃0.05 (GeV/c)2 is indicated.
No description provided.
We have measured the total inelastic cross section (σinel) and charged-particle multiplicities obtained in pp collisions at 405 GeV/c. The data are from a preliminary 12 000-picture bubble-chamber exposure. We find σinel=32.8±1.0 mb; the low moments of the multiplicity distribution for negative particles are 〈n−〉=3.50±0.07, D−=2.37±0.05, f2−=2.1±0.2, and f3−=0.1±0.9. We also present updated results at 102 GeV/c.
SUPERCEDES PRELIMINARY RESULTS IN J. W. CHAPMAN ET AL., PRL 29, 1686 (1972).
No description provided.
FIT TO ELASTIC DIFFERENTIAL CROSS SECTION FOR 0.05 < -T < 0.7 GEV**2.
None
No description provided.
Based on 150 000 photographs taken at the ZGS with the 30 inch deuterium-filled chamber we present an analysis of the elastic p d scattering reaction. Due to unrecoreded small deuteron recoils we were only able to measure the elastic cross section in the four-momentum region | t | > 0.03 (GeV/ c ) 2 . Extrapolation towards small | t | by two different methods gave us two compatible estimates of the total elastic cross section. The differential cross section was analyzed by means of the Glauber formalism both with and without the effects due to the D-wave part of the deuteron wave function. The differential cross sections of np at 5.4 GeV/ c and pn deduced from our data were compared and exhibit a crossover phenomenon.
CALCULATED USING TOTAL ELASTIC SIG(-T > 0.03 GEV**2) = 7.2 +- 0.4. THE SMALL ANGLE SCATTERING APPROXIMATION HOLDS: D(SIG)/DOMEGA(RF=LAB) = (P**2/PI)*D(SIG)/DT.
INTEGRATED CROSS SECTION USING EITHER EXPONENTIAL EXTRAPOLATION OR GLAUBER MODEL FIT FOR -T < 0.03 GEV**2.
The electroproduction of a π-meson and of a Δ(1236) nucleon resonance on hydrogen, ep → e πΔ (1236), was investigated in the two charge states π − Δ ++ and π + Δ 0 by measuring the scattered lepton and the produced π-meson in coincidence. The differential cross sections as funcions of W , q 2 , t − t min and ø πq were determine in the following kinematical region: w = (π + δ) 2 = 2.0 − 3.0 GeV , |q 2 | = |(e−e′) 2 | = 0.15 − 0.8 GeV 2 /c 2 , |t − t min | = 0-0.5 GeV 2 /c 2 with t = ( p − δ) 2 , φ πq = 0 − 360° .
W-DEPENDENCE FOR 4.0 GEV INCIDENT POSITRONS.
W-DEPENDENCE FOR 4.9 GEV INCIDENT POSITRONS.
W-DEPENDENCE FOR 5.4 GEV INCIDENT POSITRONS.
We have measured with good statistics the differential cross section for p p →π + π − , K + K − around 0°. Our data and previous results show that the s -dependence of dσ/d t has a value compatible with the appropriate baryon exchange.
No description provided.
No description provided.
No description provided.
We present results of measurements of K ± p and p p elastic scattering and of the annihilation reactions p p →π + π − and p p → K + K − at an incident laboratory momentum of 5 GeV/ c . Nearly complete angular distributions were obtained. Results are also presented for π -meson proton elastic scattering in the momentum transfer ranges 2 < − t < 8 (GeV/ c ) 2 (for π + ) and 0.16 < − t < 7 (GeV/ c ) 2 (for π − ). All measurements were done in one experimental geometry. The measured differential cross sections range from 10 to 10 −5 mb/(GeV/ c ) 2 .
-U = T + 8.486 GEV**2.
THE DATA FOR -T = 7.31 TO 8.45 GEV**2 WERE NORMALIZED TO OTHER EXPERIMENTS.
-U = T + 8.304 GEV**2.
Angular distributions of proton-proton elastic scattering have been measured for incident beam momenta of 10.0, 12.0, 14.2 and 24.0 GeV/ c over a range of lab scattering angles from 12 to 152 mrad. This is equivalent to a range of four-momentum transfer squared from about 0.1 to 6.7 GeV 2 at the highest momentum. Nucleon resonance production in the two-body reaction p + p → p + X has been studied at 24.0 GeV/ c incident momentum from 13.5 to 112 mrad by measuring the proton momentum spectra from the elastic peak down to a momentum corresponding to a missing mass of about 2.6 GeV. The new data are compared with previous results and theoretical models.
ESTIMATED 8 PCT RANDOM ERROR.
ESTIMATED 8 PCT RANDOM ERROR.
ESTIMATED 8 PCT RANDOM ERROR.
Electron-proton elastic-scattering cross sections have been measured at the Stanford Linear Accelerator Center for four-momentum transfers squared q 2 from 1.0 to 25.0 (GeVc)2. The electric (GEp) and magnetic (GMp) form factors of the proton were not separated, since angular distributions were not measured at each q 2. However, values for GMp were derived assuming various relations between GEp and GMp. Several theoretical models for the behavior of the proton magnetic form factor at high values of q 2 are compared with the data.
No description provided.
No description provided.
No description provided.
The K ∗− spectrum in the reaction K − +p → K ∗− +p has been measured at beam momenta 10.9, 13.4 and 15.9 GeV/ c using the missing mass technique. Production of the L(1770), and a Q-K ∗ (1420) enhancement are observed. Differential cross sections in the range of momentum transfer 0.12 < | t pp | < 0.40 (GeV/ c ) 2 are given. The L meson is observed with a width Γ = 100 ± 26 MeV. The mass spectrum between the L and 2.5 GeV does not show significant structure.
No description provided.
No description provided.
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