del Papa, C.
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A Measurement of the Polarization Parameter in pi- p --> K+ Sigma- Backward Scattering at 3.5-GeV/c

The CERN-Trieste collaboration Birsa, R. ; Bradamante, F. ; Daum, C. ; et al.
Nucl.Phys.B 133 (1978) 220, 1978.
Inspire Record 122588 DOI 10.17182/hepdata.35147

We have measured the polarization parameter in π − p→K + Σ − backward scattering at 3.5 GeV/ c incident momentum, in the u -range −0.6< u <0.1 GeV 2 . The apparatus consisted of a polarized target in a spectrometer magnet, counter hodoscopes for time-of-flight measurements, a large water Čerenkov counter for kaon tagging, and wire spark chambers. After identification of the kaons, the reaction was selected by a missing-mass technique. An isospin analysis has been carried out to separate the contributions of the various isospin exchange amplitudes in the u -channel.

1 data table
Table 1

No description provided.


Inclusive Double Charge Exchange $\pi^-$ Production at 100 GeV/c

Cutts, D. ; Dulude, R. ; Lanou, R.E. ; et al.
Phys.Rev.Lett. 40 (1978) 141, 1978.
Inspire Record 121767 DOI 10.17182/hepdata.20919

Measurements of inclusive cross sections at 100 GeV/c are presented for the double-charge-exchange reactions a+p→π−X with a=π, K, or p. The measurements covered a kinematic range in the Feynman x variable of 0.3<~x<~0.9 at transverse momenta of 0.3 and 0.5 GeV/c. A model summing the contributions from resonance production and from inclusive central-region π− production is used to fit the data and demonstrates the importance of resonance production via one-pion exchange for large values of the Feynman x.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Study of Neutrino Proton Elastic Scattering in the GARGAMELLE Freon Experiment

Pohl, M. ; Welch, L. ; Dewit, M. ; et al.
Phys.Lett.B 72 (1978) 489-492, 1978.
Inspire Record 122236 DOI 10.17182/hepdata.48973

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.

1 data table
Table 1

(C=OBSERVED) and (C=CORRECTED) are the observed and corrected for the nuclear effects ratios.


Study of Photons Produced Simultaneously with the J/psi Particles at the CERN Intersecting Storage Rings

Cobb, J.H. ; Iwata, S. ; Palmer, R.B. ; et al.
Phys.Lett.B 72 (1978) 497-499, 1978.
Inspire Record 122488 DOI 10.17182/hepdata.50369

As a part of the study of the inclusive production of electron pairs in pp collisions at the CERN Intersecting Storage Rings (ISR), a search has been performed for additional photons accompanying J/ψ particles. The results suggest that (43±21)% of the J/ψ's are produced via the photonic decay of one of the χ(3.5) states.

1 data table
Table 1

The cross section times branching ratio.


Production of Slow Protons in the Inclusive Reactions $p (\pi^+) n \to p_{Slow}$ + x at 195 GeV/c

Eisenberg, Y. ; Haber, B. ; Hochman, D. ; et al.
Nucl.Phys.B 135 (1978) 189-202, 1978.
Inspire Record 121977 DOI 10.17182/hepdata.35148

The inclusive reactions pn → p s + x and π + n → p s + x at incident momentum of 195 GeV/ c have been studied in an exposure of the Fermilab 30 inch deuterium filled bubble chamber to a mixed ( π + , p) beam. Analysing the t and M 2 dependence of our data within the framework of triple-Regge models we conclude that pion exchange yields a dominating contribution. Comparing our data with the pp results we conclude that isoscalar Regge exchange, ω, is much larger than isovector, ϱ, Regge exchange. We observe significant leading π − emission from the recoiling mass x, comparable to that observed in on-mass-shell π − p → π − experiments. This verifies our conclusions about pion-exchange dominance in the above reactions.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Single and Double Diffraction Dissociation in K+ p Interactions at 32-GeV/c

The French-Soviet & CERN-Soviet collaborations Saudraix, J. ; Denegri, D. ; Loret, M. ; et al.
SACLAY-DPhPE 77-19, 1977.
Inspire Record 121747 DOI 10.17182/hepdata.19296

None

1 data table
Table 1

No description provided.


Production of A20 and omega-prime (1675) in the Reaction pi+ p --> Delta++ pi+ pi- pi0 at 15-GeV/c

Baltay, C. ; Cautis, C.V. ; Kalelkar, M. ;
Phys.Rev.Lett. 40 (1978) 87, 1978.
Inspire Record 5845 DOI 10.17182/hepdata.37296

We present the results of a detailed study of ω′(1675) production in the reaction π+p→Δ++π+π−π0 from a high-statistics bubble-chamber experiment at 15 GeV/c. We have measured the mass, width, and cross section as well as differential cross section and spin density matrix elements and compare then to A20 production in the same reaction. We show clear evidence for the resonant phase increase of the 3− (ρπ)fI=0 amplitude with ω′(1675) production.

4 data tables
Table 1

No description provided.

Table 2

NOTE THAT THE SCALES FOR THE DIFFERENTIAL CROSS SECTION ARE WRONG IN THE PUBLISHED FIGURE.

Table 3

No description provided.

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Amplitude and Natural Parity Exchange Analysis of K+- p --> (K pi)+- p Data at 10-GeV/c

Martin, Alan D. ; Shimada, T. ; Baldi, R. ; et al.
Nucl.Phys.B 134 (1978) 392-412, 1978.
Inspire Record 122126 DOI 10.17182/hepdata.35128

High statistics data for the reactions K ± p → K S 0 π ± p at 10 GeV/ c are analysed. The K ∗ (1 − ), K ∗ (2 + ), and K ∗ (3 − ) resonance parameters and production cross sections are calculated. The Kπ production amplitudes are determined as a function of t and the produced Kπ mass. Isoscalar natural-parity-exchange (NPE) is dominant. The t dependence of the K ± NPE amplitudes have a cross-over at t = −0.3 (GeV/ c ) 2 for both K ∗ (890) and K ∗ (1420) production, being more pronounced for the K ∗ (1420). Natural-parity-exchange interference effects are isolated. The NPE amplitudes are decomposed into pomeron-, f-, and ω-exchange contributions. S-wave Kπ production is found to be consistent with the Kπ partial-wave analyses of charge-exchange reactions.

2 data tables
Table 1

CORRECTED FOR BACKGROUND, BREIT-WIGNER TAILS AND T-ACCEPTANCE. SYSTEMATIC ERROR INCLUDED.

Table 2

DATA FOR K PI PRODUCTION AND ANGULAR DISTRIBUTIONS ARE IN THE PRECEDING PAPER, R. BALDI ET AL., NP B134, 365 (1978).


J/psi Production by 24-GeV/c Protons

The Annecy(LAPP)-Brussels-Freiburg collaboration Bamberger, A. ; Binon, F.G. ; Bricman, C. ; et al.
Nucl.Phys.B 134 (1978) 1-13, 1978.
Inspire Record 122150 DOI 10.17182/hepdata.35143

We report measurements at the CERN PS of the production cross section of J/ψ(3.1) by 24 GeV protons on hydrogen, carbon, and tungsten.

2 data tables
Table 1

No description provided.

Table 2

ASSUME B.R.(E+E-) =0.069.


Charged Hadron Multiplicities and Inclusive pi- Distributions in Inelastic e p Scattering

Chen, C.K. ; Knowles, J. ; Martin, D. ; et al.
Nucl.Phys.B 133 (1978) 13-37, 1978.
Inspire Record 121936 DOI 10.17182/hepdata.35153

Electroproduction of hadrons is studied in the kinematic region W < 2.8 GeV and 0.3 < Q 2 < 1.4 GeV 2 using the DESY streamer chamber. Prong cross sections, charged-particle multiplicities and inclusive π − distributions are presented. The average charged multiplicity is found to be independent of Q 2 in the Q 2 range studied here; however it is lower than in photoproduction. The fraction of forward π − is found to be significantly less in electroproduction than in photoproduction. The 〈 p ⊥ 2 〉 for inclusive π − is, for all x values, similar to that found in photoproduction.

15 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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