Date

Photoproduction of two pions in the energy range of 4.1-GeV - 6.2-GeV

The Aachen-Hamburg-Heidelberg-Muenchen collaboration Struczinski, W. ; Dittmann, P. ; Eckardt, V. ; et al.
Nucl.Phys.B 57 (1973) 1-17, 1973.
Inspire Record 84071 DOI 10.17182/hepdata.32562

The reaction γp→; π + π − p in the energy range 4.1 to 6.2 GeV has been studied with a tagged photon beam incident on a liquid hydrogen target in the DESY one-meter streamer chamber. The reaction is analysed in terms of the longitudinal phase space (LPS) method. The one-pion-exchange model for Δ(1236) production and decay is examined. For the diffractive part of the LPS a dual model with pomeron exchange is investigated. In particular, the s -channel helicity conservation dual model of Dewey and Humpert describes the data well.

4 data tables

No description provided.

CORRECTED FOR LOSSES AT SMALL T (UNLIKE VALUES OF 'REF 1'). BACKGROUND SUBTRACTION ERROR HAS BEEN ADDED QUADRATICALLY TO THE STATISTICAL ERROR.

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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

No description provided.

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

No description provided.

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

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

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

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

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

No description provided.


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

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

POLARIZATION ASSUMED POSITIVE.


The reaction e+ e- ---> p anti-p at a total energy of 2.1 gev

Castellano, M. ; Di Giugno, G. ; Humphrey, J.W. ; et al.
Nuovo Cim.A 14 (1973) 1-20, 1973.
Inspire Record 87244 DOI 10.17182/hepdata.37782

An optical spark-chamber counter experiment at Adone, the Italian colliding electron-positron ring, has succeeded in measuring the cross-section for the process e+e−→p\(\bar p\) near threshold (Ec.m.=2.1 GeV). The result isσ(e+e−→p\(\bar p\))=(0.91±0.22) nb.

1 data table

ISOTROPIC ANGULAR DISTRIBUTION ASSUMED.


Properties of the b-meson observed in 11 gev/c pi+- p interactions

Afzal, M. ; Evans, D. ; Neat, K.P. ; et al.
Nuovo Cim.A 15 (1973) 61-76, 1973.
Inspire Record 86986 DOI 10.17182/hepdata.37808

Production and decay properties of the B-meson are studied in the reactions π±p→B±p at 11 GeV/c. Values for mass, width, total and differential cross-sections and spin density matrix elements are given. The spin and parity, and the helicity states in the B→πω decay, are analysed.

3 data tables

BREIT-WIGNER FIT WITH 30 PCT BACKGROUND SUBTRACTED AND CORRECTED FOR UNSEEN OMEGA DECAYS.

FOR <OMEGA PION> EVENTS IN THE B REGION (1.16 TO 1.32 GEV) WITHOUT SUBTRACTING BACKGROUND.

ASSUMING B HAS SPIN-PARITY OF 1+.