Alvarez, R.
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Elastic pi- p, k- p and anti-p p scattering at momenta of 25 and 40 gev/c

Antipov, Yu.M. ; Ascoli, G. ; Busnello, R. ; et al.
Yad.Fiz. 18 (1973) 353-363, 1973.
Inspire Record 84824 DOI 10.17182/hepdata.19259

None

1 data table
Table 1

No description provided.


rivet Analysis
Multihadronic cross-sections from e+ e- annihilation up to 3 gev center-of-mass energy

Bacci, C. ; Penson, G. ; Salvini, G. ; et al.
Phys.Lett.B 44 (1973) 533-536, 1973.
Inspire Record 84794 DOI 10.17182/hepdata.6496

With an apparatus slightly improved with respect to a previous one we have studied multihadronic production at the Adone e + e − storage ring up to a maximum center of mass energy of 3 GeV.

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Multihadron production in e+ e- collisions at high energy

Grilli, M. ; Iarocci, E. ; Spillantini, P. ; et al.
Nuovo Cim.A 13 (1973) 593-644, 1973.
Inspire Record 87243 DOI 10.17182/hepdata.1179

Multihadron production by electron-positron colliding beams has been investigated for total centre-of-mass energies ranging from 1.2 to 2.4 GeV. The total cross-section, σtot ≡ σ(e+e−→π+π−+ + anything), is of the order of σμμ ≡ σ(e+e−→μ+μ−), with a threshold near 1 GeV. Partial cross-sections for the various channels are also derived. The cross-section of the specific channel e+e−→π+π−π+π− exhibits an energy dependence which is suggestive of a heavier vector meson, ρ' (mρ,≈ 1.6 GeV,Гρ, ≈ 350 Mev), having the same quantum numbers as the ρ-meson. An upper limit is given for the coupling constantfρ′ (fρ′/4π<18, wherefρ′=mρ′2e/gγρ′). Final states withG+ parity are found to be much more abundant than those withG− parity. The average multiplicity (charged plus neutral final-state pions) is found to be betweet 4 and 5 over all the energy range explored.

3 data tables
Table 1

No description provided.

Table 2

VALUES OF R CALCULATED FROM TOTAL CROSS SECTION.

Table 3

No description provided.


Inclusive $\pi^-$ Distributions from 205-GeV/c $pp$ Interactions.

Cho, Y. ; Engelmann, R. ; Fields, T. ; et al.
Phys.Rev.Lett. 31 (1973) 413-416, 1973.
Inspire Record 81713 DOI 10.17182/hepdata.21358

Inclusive π− distributions from 205-GeV/c pp interactions, covering the full range of longitudinal and transverse momenta, have been obtained using the 30-in. hydrogen bubble chamber at the National Accelerator Laboratory. These data provide new evidence for scaling in the fragmentation region and for a plateau in the central region of rapidity. The 90°-c.m. invariant cross section varies as exp[−(10±2)PT2] in the range PT2<~0.1 (GeV/c)2.

1 data table
Table 1

No description provided.


Search for structure in pi- p ---> lambda k0 at sigma k threshold

Nelson, B. ; Knasel, T.M. ; Lindquist, J. ; et al.
Phys.Rev.Lett. 31 (1973) 901-904, 1973.
Inspire Record 83771 DOI 10.17182/hepdata.21338

We have measured the cross section, the angular distribution, and the Λ polarization for the reaction π−p→ΛK0. A spark-chamber spectrometer was used to collect 8400 ΛK0 events at fourteen beam momenta near ΣK threshold. Our data do not show the prominent cross-section enhancement suggested by some previous experiments. However, detailed structure in the cross section and the angular distribution agrees well with a simple model which includes a cusp effect at ΣK threshold.

3 data tables
Table 1

No description provided.

Table 2

BACKWARD-FORWARD PRODUCTION ASYMMETRY.

Table 3

AVERAGE LAMBDA POLARIZATION.


Large angle pi- proton elastic scattering at 14 and 23 gev/c

Cornillon, P. ; Grindhammer, Guenter ; Klems, J.H. ; et al.
Phys.Rev.Lett. 30 (1973) 403-406, 1973.
Inspire Record 84550 DOI 10.17182/hepdata.21401

The differential cross section for π−−p elastic scattering has been measured at 13.8 and 22.6 GeV/c up to −t=5 (GeV/c)2. The dips in the angular distribution at −t≈0.8 and 2.8 (GeV/c)2 previously observed at lower momenta become less prominent at higher momentum. The −t=2.8 (GeV/c)2 dip is still observed at 13.8 GeV/c, but at 22.6 GeV/c it has become a sharp kink in the angular distribution. At large momentum transfers, dσdt at fixed t is still decreasing with increasing s, but at a slower rate in the 14- to 23-GeV/c region than at lower momenta.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Hadron Production by electron positron annihilation at 4-GeV center-of-mass energy

Litke, A. ; Hanson, G. ; Hofmann, A. ; et al.
Phys.Rev.Lett. 30 (1973) 1189-1192, 1973.
Inspire Record 85252 DOI 10.17182/hepdata.21416

We have measured the total cross section for electron-positron annihilation into three or more hadrons, with at least two charged particles in the final state. The measurement was made at a center-of-mass energy of 4 GeV with a 2π−sr nonmagnetic detector. With 88 events detected, we obtain a model-independent lower limit on the hadron production cross section of 9.6 ± 1.4 nb; a calculation of detection efficiency based on invariant phase-space production of pions leads to a total cross section of 26 ± 6 nb. This cross section is 4.7 ± 1.1 times the theoretical total cross section for e+e−→μ+μ−. The average charged multiplicity is n¯=4.2±0.6.

1 data table
Table 1

No description provided.


Sigma- production in high-energy proton interactions

Hungerbuehler, V. ; Majka, R. ; Marx, J.N. ; et al.
Phys.Rev.Lett. 30 (1973) 1234-1237, 1973.
Inspire Record 84497 DOI 10.17182/hepdata.21625

Momentum spectra for forward Σ− production on beryllium by protons of momentum 25.8 and 29.4 GeVc are presented. Data for the two primary proton momenta are compared for scaling behavior in the invariant cross section. In addition, the observed single-particle momentum distributions are compared with single-particle spectra from other inclusive reactions initiated by protons.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Observation of the reaction pi- p ---> anti-p d from 4 to 6 gev/c

Pawlicki, A.J. ; Ayres, D.S. ; Diebold, R. ; et al.
Phys.Rev.Lett. 31 (1973) 665-667, 1973.
Inspire Record 83780 DOI 10.17182/hepdata.21336

Differential cross sections have been measured for the reaction π−p→p¯d. At 4 GeV/c the total cross section is 0.58 ± 0.08 μb with an angular distribution consistent with isotropy. At 5 GeV/c a pronounced forward dip occurs. In contradiction to simple baryon-exchange models, the cross section is found to be an order of magnitude smaller than that for the line-reversed reaction pp→π+d. Upper limits for π−d→p¯t were also found.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Comparison of particle-antiparticle elastic scattering from 3 to 6 gev/c

Ambats, I. ; Ayres, D.S. ; Diebold, R. ; et al.
Phys.Rev.Lett. 29 (1972) 1415-1419, 1972.
Inspire Record 84577 DOI 10.17182/hepdata.21445

Differential cross sections for π±p, K±p, pp, and p¯p elastic scattering were measured at 3, 3.65, 5, and 6 GeVc for momentum transfers from 0.03 to 1.5 GeV2 using the Argonne effective mass spectrometer. Particular attention was paid to the relative particle-antiparticle normalization. The crossover points are consistent with no energy dependence, average values being 0.14 ± 0.03, 1.190 ± 0.005, and 0.160 ± 0.007 GeV2 for π's, K's, and protons, respectively.

1 data table
Table 1

No description provided.