Alvarez, R.
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rivet Analysis
Multiplicity in hadron production by e+ e- colliding beams

Ceradini, F. ; Santonico, R. ; Conversi, M. ; et al.
Phys.Lett.B 42 (1972) 501-503, 1972.
Inspire Record 84978 DOI 10.17182/hepdata.28188

The average multiplicities 〈 n c 〉 and 〈n〉, of charged-plus-neutral pions produced in e + e − collisions, have been determined for total center-of-mass energies ranging from 1.2 to 2.4 GeV. No appreciable multiplicity variation is observed over this energy range, where the mean values 〈; n c 〉 = 3.3 +0.3 −0.2 and 〈 n 〉 = 4.4 +0.4 −0.2 are found.

2 data tables
Table 1

No description provided.

Table 2

VALUES OF R CALCULATED FROM TOTAL CROSS SECTION.


Backward pi- p elastic scattering at 3 and 4 gev/c

Brabson, A. ; Calvelli, G. ; Cittolin, S. ; et al.
Phys.Lett.B 42 (1972) 283-286, 1972.
Inspire Record 85009 DOI 10.17182/hepdata.28198

We have measured dσ du for π − p elastic scattering at 3 and 4 GeV c in the ranges −0.119⩽ u ⩽0.113 and −0.233⩽ u ⩽0.088, respectively. A fit of the form d σ /d u = A exp ( Bu + Cu 2 ) gives B = 4.34±0.42 and C = 7.0±3.5 at 4 GeV c with χ 2 = 5.7 for 9 degrees of freedom; the simpler form d σ /d u = A exp( Bu ) gives B = 3.7 ± 0.3 with χ 2 = 9.6. At 3 GeV c we confirm with high statistics the structures already observed.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


A comparison of the production of k*(890) in k+ p and k- p interactions

Carney, J.N. ; Colley, D.C. ; Jobes, M. ; et al.
Phys.Lett.B 42 (1972) 124-128, 1972.
Inspire Record 85042 DOI 10.17182/hepdata.28222

Results are presented on an analysis of the reaction K + p → K ∗+ (890) p at 16 GeV/ c and compared with data at lower incident momenta and with corresponding results for the reaction K − p → K ∗− (890) p. It is found for both reactions that the energy dependence of the cross section exhibits a simple ( p − n lab behaviour.

1 data table
Table 1

BREIT-WIGNER RESONANCE FITS WITH BACKGROUND.


A measurement of anti-p p ---> pi+ pi- and anti-p p ---> k- k+ for small values of t and u at 3 and 4 gev/c

Brabson, A. ; Calvelli, G. ; Cittolin, S. ; et al.
Phys.Lett.B 42 (1972) 287-290, 1972.
Inspire Record 85008 DOI 10.17182/hepdata.28189

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.

6 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Charged particle productions at 90 degrees in the center-of-mass in very high energy proton proton collisions

Banner, M. ; Hamel, J.L. ; Pansart, J.P. ; et al.
Phys.Lett.B 41 (1972) 547-551, 1972.
Inspire Record 85071 DOI 10.17182/hepdata.28219

The transverse momentum distribution at 90° of pions, protons and antiprotons have been measured at the CERN intersecting storage rings for C.M. energies between 23.2 and 52.7 GeV. In this energy range, the pion and proton distributions are almost energy independent. The antiproton production rises by a factor of two between 23.2 and 52.7 GeV.

3 data tables
Table 1

The invariant cross section was fitted by CONST*EXP(-SLOPE*PT).

Table 2

The invariant cross section was fitted by CONST*EXP(-SLOPE(C=1)*PT+SLOPE(C=2)*PT**2).

Table 3

No description provided.


Experimental study of the reaction $\pi^- p \to \Lambda K^0$ at beam momenta between 930 and 1130 MeV/c

Knasel, T.M. ; Lindquist, J. ; Nelson, B. ; et al.
Phys.Rev.D 11 (1975) 1-13, 1975.
Inspire Record 107188 DOI 10.17182/hepdata.24916

We have used an optical spark-chamber spectrometer to perform a systematic study of the reaction π−p→ΛK0 at beam momenta between 930 and 1130 MeV/c. The cross section, angular distribution, and Λ polarization have been measured. We present our complete data from a sample of 11 400 events along with Legendre polynomial coefficients for the angular distributions. No striking cross-section enhancement at ΣK threshold is observed, but there is evidence for a small cusp effect. A simple model which takes account of the ΣK channel provides a good fit to our data.

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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The reaction k- p ---> lambda eta from 0.80 to 1.84 gev/c

Rader, R. ; Barloutaud, R. ; Griselin, J. ; et al.
Nuovo Cim.A 16 (1973) 178-186, 1973.
Inspire Record 86997 DOI 10.17182/hepdata.37772

We present new data on the reaction K−p→Λη from 0.80 to 1.84 GeV/c. An interpretation is attempted in terms of the formation of known hyperon resonances.

3 data tables
Table 1

THE ORIGINAL DATA AT 49 MOMENTA HAVE BEEN GROUPED INTO 27 MOMENTUM BANDS. SIG = 4*PI*(REDUCED CM K- WAVELENGTH)**2*LEG(L=0).

Table 2

DATA FURTHER GROUPED INTO 9 MOMENTUM REGIONS.

Table 3

DATA FURTHER GROUPED INTO 9 MOMENTUM REGIONS.


Total cross-section measurement at the isr

Amendolia, S.R. ; Bellettini, G. ; Braccini, P.L. ; et al.
Nuovo Cim.A 17 (1973) 735-755, 1973.
Inspire Record 87700 DOI 10.17182/hepdata.37766

We present the first results of an experiment at the CERN intersecting storage rings, which measures the total cross-section in proton-proton collisions. The equivalent laboratory momenta are 291, 496, 1068 and 1480 GeV/c. We have made a direct measurement of αT as the ratio between the total interaction rate and the machine luminosity. The present paper gives a detailed description of the experimental apparatus and of the analysis procedure. We find that αT increases by about 10% in the energy region studied.

1 data table
Table 1

No description provided.


Polarization measurement of antiproton scattered elastically from proton at 220 mev

Ohsugi, T. ; Fujisaki, M. ; Kaneko, S. ; et al.
Nuovo Cim.A 17 (1973) 456-463, 1973.
Inspire Record 87646 DOI 10.17182/hepdata.37771

The polarization of scattered antiproton in\(\bar pp\) elastic scattering has been measured at the kinetic energy of 220MeV by means of double scattering in a bubble chamber. The polarizations obtained are 0.28±0.11, 0.46±0.12, 0.51±0.19 and 0.38±0.31 at the scattering angles 28°, 42°, 56° and 73° in the c.m. system, respectively. These results do not seem to be in good agreement with a prediction given by Bryan and Phillips. We have also compared these data with a modified diffraction model.

1 data table
Table 1

POLARIZATION ASSUMED POSITIVE.


Analysis of the reaction pi- p ---> p omega pi- at 9.1 gev/c

Armenise, N. ; Fogli Muciaccia, M.T. ; Silvestri, A. ; et al.
Nuovo Cim.A 17 (1973) 707-720, 1973.
Inspire Record 87699 DOI 10.17182/hepdata.37770

The reaction π-p→pωπ- has been studied at 9.1 GeV/c, its total cross-section is σ=(123±22) μb. The pB− and the quasi-three-body channels contribute with cross-section of σ=(24±7) μb and σ=(94±23) μb, respectively. The main features of the quasi-three-body pωπ- channel, displayed by some techniques of data presentation, are satisfactorily described by a double-Regge-pole model. In this model pomeron-meson and meson-meson exchanges are taken into account. An OPE modelà la Veneziano predicts a total cross-section too high and reproduces very poorly the observed features.

1 data table
Table 1

BREIT-WIGNER PLUS BACKGROUND FITS FOR B(1235)- AND OMEGA MESONS.