Gaspar, C.
SIG/SIG
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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 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

1 data table
Table 1

No description provided.


PRODUCTION OF PHOTONS ASSOCIATED WITH THE PSI BY 217-GEV/C PI- MESONS

Kirk, T.B.W. ; Raja, R. ; Goodman, M. ; et al.
Phys.Rev.Lett. 42 (1979) 619-622, 1979.
Inspire Record 145303 DOI 10.17182/hepdata.20780

Dimuon production is studied in 217-GeV/c π−-hydrogen and π−-beryllium collisions with a lead-glass array to detect photons associated with the ψ. The ψ−γ mass spectrum shows a 2.6-standard-deviation excess of events above background at ∼3.5 GeV. This excess, if attributed to the decay χ(∼3.5)→ψγ, implies that 0.70±0.28 of the ψ's are produced via radiative decay of one of the χ states.

2 data tables
Table 1

E*D(SIG)/D(XL) is fitted by (1-X)**POWER.

Table 2

No description provided.


Experimental Limits on Heavy Lepton Production by Neutrinos

Cnops, A.M. ; Connolly, P.L. ; Kahn, S.A. ; et al.
Phys.Rev.Lett. 40 (1978) 144-146, 1978.
Inspire Record 121918 DOI 10.17182/hepdata.37905

We present upper limits on the production of heavy leptons (L±) by neutrinos via the process νμ+Ne→L±+⋯, L±→e±+ν+ν¯. These limits imply that the L− and L+, if they couple in full strength to νμ, are heavier than 7.5 and 9 GeV, respectively. They also imply that the coupling strength νμ to the recently discovered 1.9-GeV heavy lepton τ is less than 0.025 of the normal νμ−μ coupling.

1 data table
Table 1

No description provided.


Study of Neutrino Proton Elastic Scattering in the GARGAMELLE Freon Experiment

Pohl, M. ; Welch, L. ; Dewit, M. ; et al.
Phys.Lett.B 72 (1978) 489-492, 1978.
Inspire Record 122236 DOI 10.17182/hepdata.48973

The cross section ratio of the elastic neutral current reaction ν p→ ν p to the quasi-elastic charged current reaction ν n→ μ − p has been measured in the kinematical region 0.3⩽ q 2 ⩽1.0 (GeV/ c ) 2 . The measured value is R M =0.17±0.08. Model dependent corrections are applied, especially for ν n→ ν n contamination, and the result is compared to various models.

1 data table
Table 1

(C=OBSERVED) and (C=CORRECTED) are the observed and corrected for the nuclear effects ratios.


Measurement of the Branching Ratio gamma (anti-p p --> e+ e-) / gamma (anti-p p --> Total) in anti-Proton-Proton Annihilation at Rest

Bassompierre, G. ; Binder, G. ; Dalpiaz, P. ; et al.
Phys.Lett.B 64 (1976) 475-478, 1976.
Inspire Record 109375 DOI 10.17182/hepdata.27616

Analyzing a sample of 220 000 events from an experiment still in progress at the CERN Proton Synchrotron (PS), 60 pairs of electrons with an energy above 700 MeV have been observed. The electrons, produced by annihilation of antiprotons stopped in a liquid-hydrogen target, are detected with optical spark chambers and scintillation counters. Twenty-nine out of these 60 pairs have been found to be collinear; normalizing with respect to the hadronic two-body channels π + π − and K + K − , a braching ratio B ee =Γ( p ̄ p → e + e − )/Γ( p ̄ p → total ) = (3.2 ± 0.9) × 10 −7 has been obtained

1 data table
Table 1

No description provided.


Inclusive rho0 Production in pi- p Interactions at 205-GeV/c

Winkelmann, F.C. ; Bingham, H.H. ; Chew, D.M. ; et al.
Phys.Lett.B 56 (1975) 101-104, 1975.
Inspire Record 91206 DOI 10.17182/hepdata.27880

The inclusive ϱ ° production cross section has been measured in the reaction π − p → π + π − X at 205 GeV/ c . We find σ ( ϱ ° ) = 13.5 ± 3.4 mb, with most of the production occuring in the central region. Assuming σ ( ϱ + ) ≈ σ ( ϱ − ) ≈ σ ( ϱ ° ), it is concluded that approximately one-third of the pions at this energy come from ϱ -decay.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Measurement of Rates for Muonless Deep Inelastic Neutrino and anti-neutrino Interactions

Aubert, Bernard ; Benvenuti, A.C. ; Cline, D. ; et al.
Phys.Rev.Lett. 32 (1974) 1457, 1974.
Inspire Record 1123 DOI 10.17182/hepdata.21890

Relative rates for deep inelastic neutrino and antineutrino scattering without a finalstate muon have been measured. For neutrinos the result is Rν=σ(νμ+nucleon→νμ+hadrons)σ(νμ+nucleon→μ−+hadrons)=0.11±0.05. The corresponding ratio for antineutrinos is Rν¯=0.32±0.09.

1 data table
Table 1

No description provided.


Further observation of muonless neutrino-induced inelastic interactions.

Aubert, Bernard ; Benvenuti, A.C. ; Cline, D. ; et al.
Phys.Rev.Lett. 32 (1974) 1454-1457, 1974.
Inspire Record 882 DOI 10.17182/hepdata.21934

We report here additional positive results of a search for muonless neutrino- and anti-neutrino-induced events using an enriched antineutrino beam and a muon identifier of relatively high geometric detection efficiency. The ratio of muonless to muon event rates is observed to be R=0.20±0.05. We observe no background derived from ordinary neutrino or antineutrino interactions that is capable of explaining the muonless signal.

1 data table
Table 1

No description provided.