Abramowicz, H.
[6.0, 7.0]
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rivet Analysis
Cross-Sections and Event Topologies in e+ e- Annihilation at 13-GeV and 17-GeV Observed with the PLUTO Detector

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.
Phys.Lett.B 81 (1979) 410-415, 1979.
Inspire Record 140294 DOI 10.17182/hepdata.45239

First results from the magnetic detector PLUTO at the new e + e − storage ring PETRA are shown. The ratio R of the cross section for hadron production to that for μ-pair production has been measured to be R = 5.0 ± 0.5 at 13 GeV and 4.3 ±0.5 at 17 GeV. Both values have an additional systematic error of 20%. The events show a typical 2-jet structure. The mean transverse momentum approaches a constant value with increasing energy implying a shrinkage of the jet opening angle.

2 data tables
Table 1

TAU HEAVY LEPTON PAIR CONTRIBUTIONS HAVE BEEN SUBTRACTED. R AT 13 AND 17 GEV, TOGETHER WITH SOME SELECTED LOWER ENERGY MEASUREMENTS FROM PLUTO AT DORIS.

Table 2

Data from earlier preprint DESY-79-06. NUMERICAL VALUES MEASURED OFF GRAPH IN PREPRINT.


NEUTRON DISSOCIATION INTO P PI- AT 19-GEV/C

Bakken, V. ; Jacobsen, T. ; Gennow, H. ; et al.
Nuovo Cim.A 49 (1979) 465-483, 1979.
Inspire Record 145707 DOI 10.17182/hepdata.37532

The reaction pn→ppπ at 19 GeV/c is studied. It is dominated by the process where the neutron dissociates into the pπ- system and exhibits the characteristic features of diffraction dissociation. The pπ- mass distribution shows a strong peak at 1.3 GeV but is otherwise rather structureless. By comparison with other experiments we find that this peak is neither seen at higher nor at lower energies. The reason why it is not seen in experiments at higher energies seems to be that they suffer from strong experimental limitations. The 1.3 GeV peak is connected with small momentum transfers and an analysis of the moments of the decay angular distributions shows that this peak is a low-spin phenomenon. For larger momentum transfers the lowest moments show an onset already at threshold. By comparison with a pion exchange Deck model we find a substantial baryon exchange contribution for small momentum transfers. This contribution seems to become more pronounced at higher energies.

1 data table
Table 1

CORRECTED FOR UNOBSERVED DECAY MODES.


Reaction $\pi^- p \to \eta n$ in the 15-{GeV}/$c$ to 40-{GeV}/$c$ Momentum Range

The Serpukhov-CERN collaboration Apel, W.D. ; Augenstein, K.H. ; Bertolucci, E. ; et al.
Nucl.Phys.B 152 (1979) 1, 1979.
Inspire Record 133409 DOI 10.17182/hepdata.41487

A high-statistics measurement of the reaction π − p→ η n; η →2 γ has been performed at the 70 GeV Serpukhov accelerator for 15, 20, 25, 30 and 40 GeV/ c incident pion momentum using the NICE set-up with its associated 648-channel hodoscope spectrometer for γ-ray detection. It is found that the spin-flip and non-spin-flip amplitudes can be parametrized, for small | t |, as exponentials with the same slopes to within a few percent. For | t | ≳ 1 (GeV/ c ) 2 there is a break in the differential cross section. In addition, the A 2 effective trajectory deviates markedly for | t | ≳ 1 GeV/ c ) 2 from the linear behaviour valid for smaller | t |.

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Pion Production at High Transverse Momentum in 24-{GeV} Proton Proton Collisions

Beier, E.W. ; Patton, R. ; Raychaudhuri, K. ; et al.
Phys.Rev.D 18 (1978) 2235, 1978.
Inspire Record 7054 DOI 10.17182/hepdata.24372

We report measurements of the inclusive π− and π+ yields in 24-GeV proton-proton collisions at θc.m.=90° for 2.2≤PT≤2.8 GeV/c. There is a high-PT deficit, rather than excess, at this incident energy.

3 data tables
Table 1

THIS DATA IS FROM AN 'UNBIASED TRIGGER' WHICH RESPONDS TO ANY CHARGED PARTICLE.

Table 2

THIS DATA IS FROM AN 'ELECTRON TRIGGER' WHICH RESPONDS ONLY TO PARTICLES THAT ARE ABOVE THRESHOLD IN > OR = 2 OF THE 3 CERENKOV COUNTERS IN THE LEAD- GLASS DETECTORS.

Table 3

THIS DATA IS FROM AN 'ELECTRON TRIGGER' WHICH RESPONDS ONLY TO PARTICLES THAT ARE ABOVE THRESHOLD IN > OR = 2 OF THE 3 CERENKOV COUNTERS IN THE LEAD- GLASS DETECTORS.


A2- Production in the Reaction $\pi^- p \to K^- K^0_S p$ at 9.8-{GeV} and 18.8-{GeV}

The CERN-Munich collaboration Chabaud, V. ; Hyams, B. ; Jones, C. ; et al.
Nucl.Phys.B 145 (1978) 349-366, 1978.
Inspire Record 131631 DOI 10.17182/hepdata.34875

Results of two spark chamber experiments on A 2 − production in the reaction π − p → K − K S 0 (→ π + π − )p at 9.8 and 18.8 GeV are presented. Decay angular distributions and differential cross sections are given, and the energy dependence of the cross section σ [ π − p → A 2 − (→ K − K 0 )p] is compared with results from π − p → A 2 − (→ 3 π )p.

4 data tables
Table 1

FITS WITH CONSTANT BACKGROUNDS. A TWO-PARAMETER LINEAR BACKGROUND GIVES MUCH LARGER ERRORS.

Table 2

INTEGRATED OVER M(K AK) = 1.20 TO 1.42 GEV.

Table 3

No description provided.

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Inclusive Electron Production in Multiprong Events Produced by $e^+ e^-$ Annihilation

Feller, J.M. ; Litke, A. ; Madaras, R. ; et al.
Phys.Rev.Lett. 40 (1978) 1677, 1978.
Inspire Record 129962 DOI 10.17182/hepdata.38080

We have measured inclusive electron production in multiprong events produced by e+e− annihilation in the center-of-mass energy range 3.9-7.4 GeV. We find the electron momentum spectra are consistent with the electrons coming mainly from decays of charmed particles, with a smaller contribution from decays of the τ lepton. From our data we calculate the average branching ratio for charmed particles to decay into an electron plus additional particles to be (8.2±1.9)%.

1 data table
Table 1

No description provided.


INVARIANT CROSS-SECTIONS FOR THE INCLUSIVE REACTIONS anti-p p ---> pi+ X AND anti-p p ---> p X AT 22.4-GeV/c

The Alma Ata-Dubna-Helsinki-Moscow-Prague collaboration Boos, E.G. ; Ermilova, D.I. ; Samoilov, V.V. ; et al.
Nuovo Cim.A 47 (1978) 377, 1978.
Inspire Record 130221 DOI 10.17182/hepdata.37561

Invariant inclusive cross-sections for π+-mesons and protons from\(\bar pp\) reactions at 22.4 GeV/c are presented. The average multiplicity for the production of π+-mesons is 1.92±0.02 and for protons 0.41±0.02. Annihilation spectra have been approximated by using the difference between\(\bar pp\) and pp data. The resulting distributions have similar gross features as the total\(\bar pp\) data.

1 data table
Table 1

No description provided.


Inclusive Neutron and Lambda Production in Proton Proton Interactions at 12-GeV/c and 24-GeV/c

The BONN-HAMBURG-MUNICH collaboration Blobel, V. ; Fesefeldt, H. ; Franz, H. ; et al.
Nucl.Phys.B 135 (1978) 379-404, 1978.
Inspire Record 135054 DOI 10.17182/hepdata.8290

A method for the determination of neutron spectra in a bubble chamber experiment is developed. Double differential cross sections for inclusive neutron and lambda production are presented. The n/Λ particle ratios are determined as functions of x and p T ; at p T = 0 GeV/ c they are compatible with the ratios measured in pCu interactions at 24 GeV/ c . Our neutron spectra are compared with spectra for protons produced near the direction of the incident neutron in pn interactions at FNAL and with neutron spectra measured in pp interactions at the ISR. Exchange mechanisms are studied in the framework of single diffraction dissociation and the triple-Regge model. The scattering of virtual pions and kaons on real protons is investigated.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


The s Dependence of Proton Fragmentation by Hadrons. 2. Incident Lab Momenta 30-GeV/c - 250-GeV/c

Weisberg, H. ; Beier, E. ; Brody, H. ; et al.
Phys.Rev.D 17 (1978) 2875, 1978.
Inspire Record 122402 DOI 10.17182/hepdata.24404

Measurements of inclusive scattering in the target-fragmentation region are extended to higher incident energy. The combined data set shows departures from an approach to the asymptotic scaling limit as A+Bs−12 that are significant even at the highest energies. When these departures are taken into account, the data approach a limit that is consistent with equal cross sections induced by particles and antiparticles and with Pomeron factorization. The corrections to A+Bs−12 are so large that detailed tests of Mueller-Regge relationships are not conclusive.

6 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Inclusive rho0 Production in anti-p p Interactions at 22.4-GeV/c

The Alma Ata-Dubna-Helsinki-Kosice-Moscow-Prague collaboration Ermilova, D.I. ; Filippova, V.V. ; Samoilov, V.V. ; et al.
Nucl.Phys.B 137 (1978) 29, 1978.
Inspire Record 122943 DOI 10.17182/hepdata.35097

Inclusive ϱ 0 production has been investigated in p p reactions at 22.4 GeV/ c . The total cross section for ϱ 0 production is 8.1 ± 2.0 mb. The average ϱ 0 's per event is 0.17 ± 0.03. The average transverse momentum, as obtained by extrapolation of a fitted simple exponential to the p T 2 distribution, is 0.52 ± 0.12 GeV/ c . The Feynman x and c.m. rapidity distributions show ϱ 0 to be “centrally” produced.

2 data tables
Table 1

No description provided.

Table 2

No description provided.