Penso, G.
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$\pi^- p$ Interactions at 360-GeV/c: Measurement of the Total and Elastic Cross-Sections and the Charged Particle Multiplicity Distribution

Firestone, A. ; Anderson, E.W. ; Chang, V. ; et al.
Phys.Rev.D 14 (1976) 2902, 1976.
Inspire Record 3926 DOI 10.17182/hepdata.24670

In a sample of 108 563 pictures taken with the Fermilab 30-inch hydrogen bubble chamber, exposed to a 360-GeV/c π− beam, we have observed 19 453 interactions in a selected fiducial region. The observed charged multiplicity distribution has been corrected for the effects of scan efficiency, errors in prong count, missed close-in vees, secondary interactions, and neutron stars and for Dalitz pairs. The two-prong events have been corrected for losses at low −t. The total cross section is measured to be 25.25 ± 0.35 mb, and the elastic cross section is 3.61 ± 0.11 mb with an exponential slope of (8.82 ± 0.30) (GeV/c)−2. The average charged-particle multiplicity for inelastic events is 8.73 ± 0.04, and the second moment f2 is measured to be 9.83 ± 0.23.

2 data tables
Table 1

SYSTEMATIC CORRECTIONS INCLUDED IN ERRORS.

Table 2

FROM FIT, FORWARD D(SIG)/DT = 31.84 +- 0.68 MB/GEV**2, AND AGREES WITH OPTICAL POINT FROM MEASURED TOTAL CROSS SECTIONS.


Inelastic Diffractive Scattering at FNAL Energies

Ayres, D.S. ; Diebold, Robert E. ; Cutts, D. ; et al.
Phys.Rev.Lett. 37 (1976) 1724, 1976.
Inspire Record 109174 DOI 10.17182/hepdata.21057

Inelastic differential cross sections have been measured for π±p, K±p, and p±p at 140- and 175-GeV/c incident momentum over a |t| range from 0.05 to 0.6 GeV2 and covering a missing-mass region from 2.4 to 9 GeV2. For Mx2 greater than 4 GeV2, the invariant quantity Mx2d2σdtdMx2 was found to be independent of Mx2 at fixed t and could be adequately described by a simple triple-Pomeron form. The values obtained for the triple-Pomeron couplings are identical within statistics for all channels.

1 data table
Table 1

Data from 140 GeV and 175 GeV are combined. The distributions are fit to CONST*(SLOPE(C=1)*T+SLOPE(C=2)*T**2).


Measurement of the Branching Ratio gamma (anti-p p --> e+ e-) / gamma (anti-p p --> Total) in anti-Proton-Proton Annihilation at Rest

Bassompierre, G. ; Binder, G. ; Dalpiaz, P. ; et al.
Phys.Lett.B 64 (1976) 475-478, 1976.
Inspire Record 109375 DOI 10.17182/hepdata.27616

Analyzing a sample of 220 000 events from an experiment still in progress at the CERN Proton Synchrotron (PS), 60 pairs of electrons with an energy above 700 MeV have been observed. The electrons, produced by annihilation of antiprotons stopped in a liquid-hydrogen target, are detected with optical spark chambers and scintillation counters. Twenty-nine out of these 60 pairs have been found to be collinear; normalizing with respect to the hadronic two-body channels π + π − and K + K − , a braching ratio B ee =Γ( p ̄ p → e + e − )/Γ( p ̄ p → total ) = (3.2 ± 0.9) × 10 −7 has been obtained

1 data table
Table 1

No description provided.


Energy Dependence of the Reactions K0(L) p --> K0(s) p, pi+ Lambda, pi+ Sigma0 from 1540-MeV to 1610-MeV

Engler, A. ; Keyes, G. ; Kraemer, R.W. ; et al.
Phys.Lett.B 63 (1976) 231-234, 1976.
Inspire Record 3809 DOI 10.17182/hepdata.27639

The reactions K L o p→K S o p, π + Λ , π + Σ o have been measured for center-of-mass energies from 1540 to 1610 MeV. Channel cross sections and coefficients of the Legendre polynomial expansion of the differential cross sections and hyperon polarizations are presented. We see no evidence in the πΛ channel for the suggested 3 2 − resonance at 1580 MeV. The cross section for the K S o p channel shows an energy dependence which is not predicted by the existing phase shift solutions based on charged kaon data.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Some 0- 1/2+ and 0- 3/2+ Final States in K- p Reactions at 14.3-GeV/c

Chaurand, B. ; Drevillon, B. ; Gago, J.M. ; et al.
Nucl.Phys.B 117 (1976) 1, 1976.
Inspire Record 109200 DOI 10.17182/hepdata.35604

We present data on K − p reactions leading to the final states K 0 n , π 0 Λ, ηΛ, η'Λ, π − Σ + , K 0 Δ 0 (1230), and π − Σ + (1385) from a bubble chamber experiment at 14.3 GeV/ c K − lab momentum. Total and differential cross sections, Λ and Σ ∓ polarisations in π 0 Λ and π − Σ + final states as well as the Σ + (1385) density matrix elements are given.

9 data tables
Table 1

NORMALIZED TO A TOTAL CROSS SECTION OF 21.5 +- 0.2 MB (GALBRAITH ET AL, PR 138B, 913 (1965)).

Table 2

No description provided.

Table 3

No description provided.

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PRISM Plot Analysis of the Reaction pi- p --> p pi+ pi- pi- at 16-GeV/c

The Aachen-Berlin-Bonn-CERN-Cracow-Heidelberg-Warsaw collaboration Grassler, H. ; Honecker, R. ; Kirk, H.G. ; et al.
Nucl.Phys.B 113 (1976) 365-377, 1976.
Inspire Record 109661 DOI 10.17182/hepdata.35583

A prism plot analysis of the reaction π − p→p π + π − π − at 16 GeV/ c has been made and the results are compared with those obtained in a similar analysis of the reaction π + p→ p π + π + π − at the same energy. The three dominating reaction mechanisms (pion dissociation, reggeon exchange, proton diffraction dissociation) appear to be well separated, while considerable residual overlaps are present inside these classes. The prism plot method is discussed as a means for detecting hidden structures and some evidence is presented for a broad three-pion enhancement around 2 GeV decaying primarily into ϱ 0 π − .

2 data tables
Table 1

No description provided.

Table 2

A4(1900) IS CALLED A*(1800) BY AUTHORS. PI+ P CROSS SECTIONS PREVIOUSLY PUBLISHED IN M. DEUTSCHMANN ET AL., NP B99, 397 (1975).


Inclusive Production of Low-Momentum Charged Pions at x=0 at the CERN Intersecting Storage Rings

The British-Scandinavian-MIT collaboration Guettler, K. ; Duff, B.G. ; Prentice, M.N. ; et al.
Phys.Lett.B 64 (1976) 111-116, 1976.
Inspire Record 109344 DOI 10.17182/hepdata.5511

Results are reported for the invariant differential cross-section of charged pions produced at x = 0 in proton-proton collisions at the CERN ISR. The range covered is 40 to 400 MeV/c in transverse momentum and 23 to 63 GeV in collision energy. The inclusive cross-section for π + and π − are increasing by 36 ± 2% and 41 ± 2%, respectively over the ISR energy range with a somewhat stronger increase at the lowest transverse momenta. The transverse momentum distribution is well described by an exponential in the transverse energy.

10 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Resonance Production in the Reaction K+ p --> K0 p pi+ at 5-GeV/c, 8.25-GeV/c and 16-GeV/c

Colley, D.C. ; Carney, J.N. ; James, M.F. ; et al.
Nucl.Phys.B 110 (1976) 333-354, 1976.
Inspire Record 108770 DOI 10.17182/hepdata.35742

We present a systematic analysis of the production of K ∗+ (892) and Δ ++ (1236) resonances in the K + p → K 0 p π + reaction at 5, 8.25 and 16 GeV/ c . We have measured total cross sections, differential cross sections, density matrix elements and examined resonance production mechanisms in terms of the exchange of states with definite naturality. Some results on the reaction K + p → K ∗+ (1420) p are also given.

6 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Experimental Results on Diffractive One Pion Production at the CERN ISR

de Kerret, H. ; Nagy, E. ; Regler, M. ; et al.
Phys.Lett.B 63 (1976) 477-482, 1976.
Inspire Record 109254 DOI 10.17182/hepdata.27619

New experimental results are reported on diffractive dissociation of protons into (nπ + ) in proton-proton collisions at a centre-of-mass energy of s = 45 GeV . The data were obtained using the Split-Field-Magnet detector at the CERN Intersecting Storage Rings. We have searched for resonance contributions and found peaks at mass values of 1.5 GeV, 1.65 GeV, and 2.1 GeV. A dip in d σ d t is observed at low t and low mass; it is most pronounced for events with neutrons emitted at 90° in the Gottfried-Jackson frame. The correlation between mass and slope depends strongly on θ J . The cross section of the channel pp → pnπ + is 400 ± 110 μb at s = 45 GeV , giving an energy dependence of s −0.30±0.07 for isospin exchange zero in this channel.

3 data tables
Table 1

SCALE UNCERTAINTY 20 PCT IS INCLUDED IN ERROR.

Table 2

SIG(P P --> P N PI+) IS NEARLY EQUAL TO SIG(P P --> P (N PI+)) WHICH WAS ACTUALLY MEASURED, SINCE THE CROSS SECTION OF THE REACTION P P --> N (P PI+) IS LESS THAN .1 MUB AS MEASURED BY N. KWAK ET AL., PL 62B, 359, 1976.

Table 3

EXTRAPOLATING TO T=0 AND ALLOWING FOR OTHER DECAY MODES YIELDS RESULT.


Elastic Scattering Crossovers from 50-GeV to 175-GeV

The Fermilab Single Arm Spectrometer Group collaboration Anderson, R.L. ; Anelli, E.F. ; Ayres, D.S. ; et al.
Phys.Rev.Lett. 37 (1976) 1025, 1976.
Inspire Record 108810 DOI 10.17182/hepdata.21092

A comparison of K±p and p±p elastic scattering is made for incident energy 50 to 175 GeV. Average values of 0.19±0.04 and 0.11±0.02 GeV2 were found for the invariant-momentum-transfer values of the Kp and pp crossover points, respectively.

1 data table
Table 1

KP AND PP CROSSOVER POINTS AT -T = 0.19 +- 0.04 AND 0.11 +- 0.02 GEV**2 (AVERAGE VALUES) RESPECTIVELY.