HEPData Search

Showing 10 of 230 results

Multiplicity, Momentum and Angular Characteristics of $\pi^-$ Mesons for $p$ C, $d$ C, $\alpha$ C and C C Interactions at 4.2-{GeV}/$c$ Per Nucleon

The Alma Ata-Baku-Belgrade-Bucharest-Dubna-Kishinev-Leipzig- Moscow-Prague-Samarkand-Sofiya-Tashkent-Tbilisi-Ulan Bator-Varna collaboration Agakishiev, G.N. ; Akhababian, N. ; Armutliisky, D. ; et al.

Z.Phys.C 27 (1985) 177, 1984.

Inspire Record 203342 DOI 10.17182/hepdata.1999

Light ion collisions with carbon target at 4.2 GeV/c/N are studied. Pion multiplicity distributions, momentum and angular spectra are analysed. These data are described in terms of models assuming independent interactions of nucleons from the projectile nucleus with the target.

18 data tables

Table 1

No description provided.

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High Statistics Study of ($\sim$ 10$^6$ events) of $J/\psi$ Production and $\Upsilon$ Production in the energy range 150 to 280 GeV by $\pi^\pm$, $p^\pm$ incident particle

The Saclay-CERN-College de France-Ecole Poly-Orsay collaboration Badier, J. ; Boucrot, J. ; Bourotte, J. ; et al.

AIP Conf.Proc. 68 (1981) 201-204, 1981.

Inspire Record 154782 DOI 10.17182/hepdata.49656

We have performed in the NA3 experiment the study of high mass dimuon production by a hadronic unseparated beam on hydrogen and platinum targets. The comparison of the production cross‐section for proton and antiproton together with the differential cross‐section dσ/dx allows us to compare the data with a production mechanism involving quark‐antiquark and gluon‐gluon interactions. The cosΘ* distribution of the same J/ψ data have also been analysed and results will be presented. Finally we have observed T production from 150 GeV/c incident pions.

4 data tables

Table 1

No description provided.

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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.

Inclusive $\rho^0$ Production in Anti-neutrino $p$ Charged Current Interactions

Derrick, M. ; Gregory, P. ; Lopinto, F. ; et al.

Phys.Lett.B 91 (1980) 307-310, 1980.

Inspire Record 8534 DOI 10.17182/hepdata.6495

Using data from the Fermilab 15 ft hydrogen bubble chamber, we have studied inclusive ϱ 0 production in antineutrino-proton charged-current interactions. We measure (0.21 ± 0.03) ϱ 0 /event, corresponding to ϱ 0 / π − =0.12 ± 0.02. As a function of Q 2 and for hadronic masses above a threshold region, the ϱ 0 / π − ratio shows little variation. At least 50% of the ϱ 0 's are consistent with coming from the current fragmentation region. The results agree reasonably well with the predictions of the quark fragmentation model of Feynman and field.

4 data tables

Table 1

AVERAGE BEAM ENERGY 31 GEV.

Table 2

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Confirmation of the Existence of the $\Sigma_c$ $^{++}$ and $\Lambda_c$ $^+$ Charmed Baryons

Baltay, C. ; Caroumbalis, D. ; French, H. ; et al.

Phys.Rev.Lett. 42 (1979) 1721, 1979.

Inspire Record 140761 DOI 10.17182/hepdata.50280

In a broadband neutrino exposure of the Fermilab 15-ft bubble chamber, we observe the production of the Σc++(2426) charmed baryon followed by its decay to Λc+(2260) and π+. We find the mass of the Λc+ to be 2257±10 MeV and the m(Σc++)−m(Λc+) mass difference to be 168±3 MeV. Previously unseen two-body decay modes of the Λc+(2260) are observed.

1 data table

Table 1

No description provided.

Measurement of the Relative Total Hadronic Cross-section R at {PETRA}

The Aachen-DESY-Annecy(LAPP)-MIT-NIKHEF-Beijing collaboration Barber, D. ; Becker, U. ; Boehm, A. ; et al.

Phys.Rev.Lett. 42 (1979) 1113, 1979.

Inspire Record 140059 DOI 10.17182/hepdata.3235

We report the first measurement of the ratio R=(σe+e−→hadrons)(σe+e−→μ+μ−) (with negligible τ-lepton contribution) at a center-of-mass energy s=13 GeV and s=17 GeV, from the just finished electron-positron colliding-beam facility PETRA. The detector, MARK-J, has an approximately 4π solid angle and measures γ, e, μ, and charged and neutral hadrons simultaneously. Our results yield R(s=17 GeV)=4.9±0.6 (statistical) ±0.7 (systematic error), and R(s=13 GeV)=4.6±0.5 (statistical) ±0.7 (systematic error). The ratio R(s=17 GeV)R(s=13 GeV) is 1.08±0.18.

2 data tables

Table 1

No description provided.

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Measurement of the Elastic Scattering of Neutrinos and Anti-neutrinos by Protons

Entenberg, A. ; Horstkotte, J. ; Kozanecki, W. ; et al.

Phys.Rev.Lett. 42 (1979) 1198, 1979.

Inspire Record 140053 DOI 10.17182/hepdata.20799

We have observed 217 (66) events of the process νp→νp (ν¯p→ν¯p) with an estimated background of 82 (28). The neutral-to-charged-current ratios are σ(νp→νp)σ(νn→μ−p)=0.11±0.02 and σ(ν¯p→ν¯p)σ(ν¯p→μ+n)=0.19±0.05 for 0.40<Q2<0.90 (GeV/c)2, where -Q2 is the square of the momentum transfer to the nucleon. These yield σ(ν¯p→ν¯p)σ(νp→νp)=0.53±0.17. The neutral-current form factors at Q2=0 are GE=0.5−0.5+0.25, GM=1.0−0.04+0.35, and gA=0.5−0.15+0.2.

1 data table

Table 1

No description provided.

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.

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