Amaldi, E.
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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.


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
Table 1

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

Table 2

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

Table 3

ASSUMING B HAS SPIN-PARITY OF 1+.


Hadron pair production by electron-positron colliding beams

Barbiellini, G. ; Grilli, M. ; Iarocci, E. ; et al.
Lett.Nuovo Cim. 6S2 (1973) 557-565, 1973.
Inspire Record 86306 DOI 10.17182/hepdata.37335

None

1 data table
Table 1

THIS HADRON PAIR CROSS SECTION PROVIDES ONLY AN UPPER LIMIT TO THE PION FORM FACTOR ABOVE 1.5 GEV SINCE KAON PRODUCTION IS NOT DISTINGUISHED.


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
Table 1

ISOTROPIC ANGULAR DISTRIBUTION ASSUMED.


Analysis of the reaction gamma n ---> p pi- in the first and second resonance regions

Rossi, V. ; Piazza, A. ; Susinno, G. ; et al.
Nuovo Cim.A 13 (1973) 59-89, 1973.
Inspire Record 87242 DOI 10.17182/hepdata.37785

The final results of an experimental investigation of the reaction γ+n→p+π− performed with a deuterium bubble chamber at the 1 GeV Frascati electrosynchrotron are presented. Total and differential cross-sections on neutrons are extracted by means of the spectator model, the reliability of which has been checked by numerous tests and is extensively discussed. The problems of a possible isotensor component in the electromagnetic current, the time-reversal invariance of the electromagnetic interactions and the photoproduction of the Roper resonance are considered in detail.

21 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Production of high transverse momentum particles in p p collisions in the central region at the CERN ISR

The British-Scandinavian ISR collaboration Alper, B. ; Boggild, H. ; Jarlskog, G. ; et al.
Phys.Lett.B 44 (1973) 521-526, 1973.
Inspire Record 85256 DOI 10.17182/hepdata.28095

The inclusive production al all charged particles of transverse momentum p T between 1.5 and 4.4 GeV/ c at centre of mass angles 90° and 59.4° from p-p-collisions with √ s = 44 and 53 GeV has been measured. No strong energy dependence is observed for these transverse momenta.

6 data tables
Table 1

Errors are statistical only.

Table 2

Errors are statistical only.

Table 3

Errors are statistical only.

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Electroproduction of rho0 mesons at 1.5 > q-squared > 0.3 gev-squared and 2.8 > w > 1.7 gev

Eckardt, V. ; Gebauer, H.J. ; Joos, P. ; et al.
Phys.Lett.B 43 (1973) 240-244, 1973.
Inspire Record 84944 DOI 10.17182/hepdata.28153

Production and decay characteristics of electroproduced rho mesons were studied in the final state epπ + π − .

1 data table
Table 1

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.


The time-like electromagnetic form factors of the charged pseudoscalar mesons from 1.44-GeV**2 to 9.0-GeV**2.

Bernardini, M. ; Bollini, D. ; Brunini, P.L. ; et al.
Phys.Lett.B 46 (1973) 261-264, 1973.
Inspire Record 85277 DOI 10.17182/hepdata.28063

The study of 620 hadron pairs produced in the s -range (1.44−9.0) GeV 2 , has yielded 110 collinear hadronic events. Their identification in terms of π and K mesons allows the determination of the time-like electromagnetic from factors of these pseudoscalar mesons in the above time-like range. The total number of (e + e − ) events observed in the same experimental conditions is 18 048.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


The Energy dependence of the proton proton total cross-section for center-of-mass energies between 23 and 53 GeV

Amaldi, U. ; Biancastelli, R. ; Bosio, C. ; et al.
Phys.Lett.B 44 (1973) 112-118, 1973.
Inspire Record 83729 DOI 10.17182/hepdata.28110

Measurements of proton-proton elastic scattering at angles around 6 mrad have been made at centre-of-mass energies of 23, 31, 45 and 53 GeV using the CERN Intersecting Storage Rings. The absolute scale of the cross-section was established by determination of the effective density of the colliding beans in their overlap region. Proton-proton total cross sections were deduced by extrapolation of the elastic differential cross-section to the forward direction and by application of the optical theorem. The results indicate that over the energy range studied the proton-proton total cross-section increases from about 39 to about 43 mb.

2 data tables
Table 1

No description provided.

Table 2

NEW VALUES OF ELASTIC SLOPE USING APPARATUS DESCRIBED IN U. AMALDI ET AL., PL 43B, 231 (1973).