Pierazzini, G.
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Charged Baryon and Anti-baryon Production in the Fragmentation Region by 240-{GeV} Protons

The Bristol-Geneva-Heidelberg-Orsay-Rutherford-Strasbourg collaboration Bourquin, M. ; Brown, R.M. ; Chatelus, Y. ; et al.
Z.Phys.C 5 (1980) 275, 1980.
Inspire Record 153261 DOI 10.17182/hepdata.15026

Measurements of the production inp-BeO collisions of charged baryons and antibaryons with strangeness between −3 and +3 at\(\sqrt s= 21.2GeV\)x=0.48, andpT=600MeV/c are reported. The experimental results can be interpreted within the framework of a simple proton fragmentation-recombination model.

5 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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A Determination of the Total Width of the $\Upsilon$ (9.46) Meson

Albrecht, H. ; Childers, R. ; Darden, C.W. ; et al.
Phys.Lett.B 93 (1980) 500-504, 1980.
Inspire Record 153029 DOI 10.17182/hepdata.6334

Using the DASP detector at the DESY storage ring DORIS we have continued measuring e + e − annihilations near and on the ϒ(9.46) resonance. From the cross sections for e + e − → μ + μ − and e + e − → hadrons we obtain a μ + μ − branching ratio for the ϒ(9.46) of (2.9 ± 1.3 ± 0.5) %, a leptonic width г ee = (1.35 ± 0.11 ± 0.22) keV and a total width of (47 −15 +37 keV.

2 data tables
Table 1

VISIBLE HADRONIC CROSS SECTION. PEAK VALUE AT UPSILON IS 10.1 +- 0.7 NB.

Table 2

No description provided.


Observation of a Fourth Upsilon State in e+ e- Annihilations

The CLEO collaboration Andrews, D. ; Berkelman, Karl ; Cabenda, R. ; et al.
Phys.Rev.Lett. 45 (1980) 219, 1980.
Inspire Record 153182 DOI 10.17182/hepdata.20674

A fourth state in the upsilon energy region has been seen in e+e− collisions at the Cornell Electron Storage Ring. A resonance is observed with a mass 1112±5 MeV above the lowest upsilon state. The 9.6-MeV rms width is greater than the 4.6-MeV energy resolution of the e+e− beams. The observed characteristics of the new state make it a likely candidate for the 4S3 state of the bb¯ system, lying above the threshold for the production of B mesons.

1 data table
Table 1

NOT CORRECTED FOR TAU HEAVY LEPTON PRODUCTION NOR TWO-PHOTON COLLISIONS.


Test of {QED} in $e^+ e^-$ Annihilation at Energies Between 12-{GeV} and 31.6-{GeV}

The TASSO collaboration Brandelik, R. ; Braunschweig, W. ; Gather, K. ; et al.
Phys.Lett.B 94 (1980) 259-265, 1980.
Inspire Record 153127 DOI 10.17182/hepdata.45228

We have measured the reactions e + e − → e + e − → μ + μ − and e + e − → γγ at c.m. energies between 12 and 31.6 GeV. Excellent agreement with the predictions of QED has been found, resulting in cut off parameters Λ + > 112 GeV and Λ − > 139 GeV for the first process and Λ + > 34 GeV and Λ − > 42 GeV (95% c.1.) for the last one. A limit on the Weinberg angle of sin 2 θ W < 0.55 (95% c.1.) has been obtained.

3 data tables
Table 1

SIG(C=QED) QED predictions for the cross sections. Only statistical errors are given.

Table 2

SIG(C=QED) QED predictions for the cross sections. Only statistical errors are given.

Table 3

SIG(C=QED) QED predictions for the cross sections. Only statistical errors are given.


Photoproduction of $K^+ K^-$ Pairs on Hydrogen at Photon Energies of 20-{GeV} to 36-{GeV}

The Bonn-CERN-Ecole Poly-Glasgow-Lancaster-Manchester-Orsay-Paris-Rutherford-Sheffield collaboration Aston, D. ; Atkinson, M. ; Bailey, R. ; et al.
Nucl.Phys.B 172 (1980) 1-12, 1980.
Inspire Record 153022 DOI 10.17182/hepdata.34516

The reaction γ p→K + K − p has been investigated with photons in the energy range of 20< E γ <36 GeV and with K + K − pairs in the mass range of M K + K − <2.0 GeV. The production of the φ(1019) contributes with a cross section σ ( γ p → φ p) × BR( φ →K + K − ) = 240±6 nb with an additional systematic error of ±20 nb. In the higher mass range of 1.05< M K + K − <2.0 GeV the production of K + K − pairs yields a cross section σ ( γ p→K + K − p) = 160±8 nb with an additional systematic error of +40 −30 nb.

3 data tables
Table 1

No description provided.

Table 2

K+ K- PRODUCTION ABOVE PHI MASS.

Table 3

No description provided.


Search for the Production of a New Quark Flavor at the Highest {PETRA} Energies

Barber, D.P. ; Becker, U. ; Benda, H. ; et al.
Phys.Rev.Lett. 44 (1980) 1722, 1980.
Inspire Record 152616 DOI 10.17182/hepdata.20702

This paper reports the results of a study of hadron production in e+e− collisions at c.m. system energies of 33, 35, and 35.8 GeV. Production of a new quark flavor has been sought. The measured values of the total cross section, the thrust distributions, and the study of inclusive muon production show no evidence for the production of a new charge-23e quark near threshold. In addition, during an energy scan in the region 29.9<~s<~31.6 GeV, no hadron resonance indicating the existence of a bound state composed of charge-23e quarks has been found.

3 data tables
Table 1

No description provided.

Table 2

ENERGY SCAN IN 20 MEV STEPS.

Table 3

THRUST DISTRIBUTION (1/N)*DN/DTHRUST AT 29.9 TO 31.6 AND 35 GEV. THESE DATA ARE RATHER DETECTOR DEPENDENT.


Study of Low-energy Anti-neutrino Interactions on Protons

Fanourakis, G. ; Resvanis, L.K. ; Grammatikakis, G. ; et al.
Phys.Rev.D 21 (1980) 562, 1980.
Inspire Record 9011 DOI 10.17182/hepdata.24171

We present a study of antineutrino interactions in hydrogen obtained in a 138000-picture run at the BNL 7-ft bubble chamber. The antineutrino beam had an energy distribution that peaked at ∼1.1 GeV. The cross section measured for charged-current interactions is σ(ν¯p→μ++anything)=(0.32±0.08)×10−38×[Eν¯ (GeV)] cm2. The neutral-current cross section is σ(ν¯p→ν¯pπ+π−)=5.5−2.6+4.4×10−40 cm2. The ratio of strangeness-changing to non-strangeness-changing charged currents is Rs=0.06−0.05+0.13. An upper limit determined for charm production is σc<3.8×10−40 cm2 at the 90% confidence level. From the momentum-transfer distribution we measure average Q2 for inelastic charged-current events with energy greater than 2 GeV, 〈Q2〉=(0.10±0.03)[Eν¯ (GeV)]+(0.10±0.09) (GeV/c)2. Using a maximum-likelihood method we determine from the quasielastic events ν¯p→μ+n an axial-vector mass MA=0.9−0.3+0.4 GeV/c2.

1 data table
Table 1

Measured charged current total cross section.


Electroproduction of $\rho^0$ Mesons

Cohen, I. ; Erickson, R. ; Messing, F. ; et al.
Phys.Rev.D 25 (1982) 634, 1982.
Inspire Record 152921 DOI 10.17182/hepdata.47139

Cross sections for ρ0 electroproduction measured in a streamer-chamber experiment are separated into elastic (ep→epρ0) and inelastic production channels. For the elastic channel, the total cross section and t dependence are presented. For the inelastic channel (1σ)dσdz, (1σ)dσdpT2, and a density matrix element are shown and compared to quark-parton-model predictions. The ratio of ρ0 to direct π0 production is found to be 2.0±0.5±0.3, where the first error is statistical, and the second error is systematic.

8 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Diffraction Dissociation, Resonances and Deck Mechanism in the $K \omega$ Systems of the Reactions $K^+^- p \to$ ($K^+^- \omega$) $p$

The Aachen-Berlin-CERN-London-Vienna & Birmingham-Brussels-CERN-Mons-Serpukhov collaborations Otter, G. ; Rudolph, G. ; Wieczorek, H. ; et al.
Nucl.Phys.B 181 (1981) 1-21, 1981.
Inspire Record 153195 DOI 10.17182/hepdata.34348

A study is presented of the reactions K + p→(K + ω )p at 8.25 and 16 GeV/ c and K − p→(K − ω )p at 10 and 16 GeV/ c and comparison is made with K + results at 10 GeV/ c and K − at 7.3 GeV/ c . The (K + ω) and (K − ω) mass spectra both present a strong enhancement very near threshold, while a second peak at ∼1.7 GeV is evident only with incident K − at the lower energies. The threshold peak has very weak energy dependence and is mostly due to the 1 + S state which is produced conserving s -channel helicity. It is suggested that this is another decay mode of the resonance Q 1 (1290) known to decay mainly into Kϱ. The ratio of the Q 1 coupling constants to the Kω and Kϱ decay channels, R ω = g K ω 2 / g K ϱ 2 is determined to be 0.21±0.04. The enhancement at 1.7 GeV is predominantly, but not exclusively, due to the 2 − state. While the K + and K − induced reactions give basically similar results, small differences are observed that can be qualitatively explained in the framework of the Deck model.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


General Features of the Anti-p $p$ Interaction at 12-{GeV}/c

Johnson, P. ; Mason, P. ; Muirhead, H. ; et al.
Nucl.Phys.B 173 (1980) 77-92, 1980.
Inspire Record 8886 DOI 10.17182/hepdata.34472

Simple inclusive cross sections for p p interactions at 12 GeV/ c are given. The data cover prong cross sections, V 0 production and resonances. Separation has been made into annihilation and non-annihilation modes. Some implications of the data are discussed. It is pointed out that the ratios of cross sections for ϱ 0 π − production are independent of incident antiproton momentum in p p annihilation processes, and that data at the highest available pp energies (ISR) tend to the same value.

1 data table
Table 1

NORMALIZED TO A TOTAL CROSS SECTION OF 51.7 +- 0.8 MB.