Althoff, M.
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Elastic and total $\pi^{+}\pi^{-}$ cross-sections from a high statistics measurement of the reaction $\pi^{-}p \to \pi^{+}\pi^{-}n$ at 63 GeV/c

Weilhammer, P. ; Berglund, A. ; Chabaud, V. ; et al.
2 (1979) 628-635, 1979.
Inspire Record 148986 DOI 10.17182/hepdata.75420

A sample of about 230000 events of the reaction pi /sup -/p to pi /sup +/ pi /sup -/n, measured with a magnetic forward spectrometer set up in an unseparated pi /sup -/ beam with a momentum of 63 GeV/c at the SPS has been analysed in terms of one pion exchange. The elastic pi /sup +/ pi /sup -/ cross section has been determined using an extrapolation to the pion pole in the mass range up to m( pi /sup +/ pi /sup -/)=4 GeV. The total pi /sup +/ pi /sup -/ cross section is obtained via the optical theorem. (7 refs).

5 data tables
Table 1

INTEGRATED 2- S-WAVE INTENSITY FOR 1500 TO 1800 MEV, INCLUDING SIGNIFICANT BACKGROUND.

Table 2

No description provided.

Table 3

No description provided.

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Average Charged Particle Multiplicities in $\pi^- P$ Inclusive Reactions at 147-{GeV}/$c$

Brick, D. ; Fong, D. ; Heller, M. ; et al.
Phys.Rev.D 19 (1979) 743, 1979.
Inspire Record 140350 DOI 10.17182/hepdata.4430

The experimentally determined average charged-particle multiplicities, 〈nX〉, of the systems, X, produced in the following reactions for 147 GeV/c incident pion momentum are presented as functions of the square of the invariant mass of X, MX2, and of |t|:π−p→πfast−X, π−p→pX, π−p→Δ++X, π−p→(π−π+)ρ0X, and π−p→Λ0X. Details of the analysis are discussed. These data can be fit by the expression 〈nX〉=A+B ln MX2+C|t| and the coefficients obtained for B are equal within their uncertainties. C is significantly different from zero only for π−p→πfast−X. These results and 〈nX〉 data from other inclusive and total-inelastic-reaction studies are discussed in terms of a simple model which assumes contributions to 〈nX〉 from the target-fragmentation, the central, and the beam-fragmentation regions in the case of total-inelastic reactions. For inclusive reactions, either the beam or target fragmentation is replaced by an exchange-particle-fragmentation contribution. The s, t, and MX2 dependence of the parameters of the model are deduced from triple-Regge considerations. The data are found to be consistent with the model and values are presented for the parameters.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Study of Resolved High {P(T)} Neutral Pions at the {CERN} {ISR}

Kourkoumelis, C. ; Resvanis, L.K. ; Voulgaris, G. ; et al.
Phys.Lett.B 83 (1979) 257-260, 1979.
Inspire Record 140588 DOI 10.17182/hepdata.27353

The inclusive production of π 0 at large values of p T in pp collisions at the ISR has been studied. In this experiment the two photons are resolved and separately measured for p T values of up to 6 GeV/ c , giving confidence that the desired signal has been separated from various backgrounds.

1 data table
Table 1

No description provided.


rivet Analysis
Properties of Hadron Final States in e+ e- Annihilation at 13-GeV and 17-GeV Center-Of-Mass Energies

The TASSO collaboration Brandelik, R. ; Braunschweig, W. ; Gather, K. ; et al.
Phys.Lett.B 83 (1979) 261-266, 1979.
Inspire Record 140303 DOI 10.17182/hepdata.27352

We have observed e + e − hadrons at C.M. energies of 13 GeV and 17 GeV at PETRA using the TASSO detector. We find R (13 GeV) = 5.6 ± 0.7 and R (17 GeV) = 4.0 ± 0.7. The additional systematic uncertainty is 20%. Comparing inclusive charged hadron spectra we observe scaling between 5 GeV and 17 GeV for x = p / p beam > 0.2; however the 13 GeV cross section is above the 17 GeV cross section for smaller x . This may be due to copious bb̄ production. The events become increasingly jet like at high energies as evidenced by a shrinking sphericity distribution with increasing energy.

2 data tables
Table 1

TAU HEAVY LEPTON CONTRIBUTION SUBTRACTED.

Table 2

THESE DATA FOR S*D(SIG)/DX AT 13 AND 17 GEV ARE INCLUDED IN THE RECORD OF R. BRANDELIK ET AL., PL 89B, 418 (1980).


Inclusive $\rho^0$ and F Production in $p p$ Interactions at 405-{GeV}/$c$

Suzuki, A. ; Kichimi, H. ; Cooper-Sarkar, Amanda M. ; et al.
Lett.Nuovo Cim. 24 (1979) 449, 1979.
Inspire Record 140494 DOI 10.17182/hepdata.37962

None

5 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Test of Quantum Electrodynamics at {PETRA} Energies

The Aachen-DESY-Annecy(LAPP)-MIT-NIKHEF-Beijing collaboration Barber, D. ; Becker, U. ; Benda, H. ; et al.
Phys.Rev.Lett. 42 (1979) 1110, 1979.
Inspire Record 140093 DOI 10.17182/hepdata.20817

We report on the measurement of the reaction e+e−→e+e− with a large—solid-angle electromagnetic shower detector at center-of-mass energies s=13 and 17 GeV. Comparison of our results with predictions of quantum electrodynamics shows excellent agreement in both the angular distribution and energy dependence. Values of cutoff parameters are also given.

1 data table
Table 1

No description provided.


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.


Photoproduction of Neutral Pions in the Region of the Fourth Nucleon Resonance

Althoff, K.H. ; Gies, M. ; Kaul, O. ; et al.
Z.Phys.C 1 (1979) 257, 1979.
Inspire Record 140695 DOI 10.17182/hepdata.50276

We report the measurement of the differential cross section of the reaction γ +p→π0 +p at a photon energy of 1.4 GeV and pion c.m. angles between 60 and 175 degrees. The angular distribution confirms the simple quark model prediction of a pure magnetic excitation of theF37 (1950) resonance.

1 data table
Table 1

No description provided.


rivet Analysis
Measurement of Leptonic Branching Ratios of the $\Upsilon$ (9.46)

The PLUTO collaboration Berger, Christoph ; Lackas, W. ; Raupach, F. ; et al.
Z.Phys.C 1 (1979) 343, 1979.
Inspire Record 140818 DOI 10.17182/hepdata.16475

The electronic width Γee and the muonic branching ratioBμμ=Γμμ/Γtot of the Γ(9.46) have been measured as Γee=(1.33±0.14) andBμμ=(2.2±2.0)%. From these values a lower limit of Γtot<23keV for the total width of the Γ(9.46) is obtained.

2 data tables
Table 1

THE DATA POINTS INCLUDE 10 PCT OF THE TAU HEAVY LEPTON PAIR EVENTS.

Table 2

NUMERICAL VALUES MEASURED OFF GRAPH IN PREPRINT.


A MEASUREMENT OF THE K0(L) p ELASTIC CROSS-SECTION FOR 3 less than or equal to p less than or equal to 13-GeV/c AND .1 less than or equal to |t| less than or equal to 1.3-GeV**2

Cittolin, S. ; Gasparini, F. ; Limentani, S. ; et al.
Nucl.Phys.B 157 (1979) 197-211, 1979.
Inspire Record 7663 DOI 10.17182/hepdata.34662

The cross section for the K L 0 p elastic scattering has been measured for the first time. The incident momentum and momentum transfer ranges are 3 ⩽ p ⩽ 13 GeV/ c , 0.1 ⩽ | t | ⩽ 1.3 GeV 2 . The results are compared to those of other experiments related to ours by isotopic spin conservation, finding agreement with some and discrepancies with others. The differential cross sections have been parametrized in the form A e bt . The coefficients show little or no dependence on energy, with A ≅ 9.8 mb · GeV −2 and b ≅ 4.7 GeV −2 . The effective linear trajectory has been determined and gives α 0 = 0.95 ± 0.15, α ′ = −0.35 ± 0.48 GeV −2 , in good agreement with dominance by pomeron exchange.

3 data tables
Table 1

CROSS SECTIONS DEDUCED FROM THE 46 PCT OF EVENTS WHICH YIELD UNIQUE SOLUTIONS.

Table 2

<RAW> CROSS SECTIONS DEDUCED FROM A STATISTICAL TREATMENT OF ALL EVENTS.

Table 3

<SMOOTHED> CROSS SECTIONS DEDUCED FROM A STATISTICAL TREATMENT OF ALL EVENTS.