Albajar, C.
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rivet Analysis
A Measurement of the Leptonic Branching Ratios of the $\Upsilon$ (1s), $\Upsilon$ (2s), and $\Upsilon$ (3s)

The CLEO collaboration Andrews, D. ; Avery, P. ; Berkelman, Karl ; et al.
Phys.Rev.Lett. 50 (1983) 807, 1983.
Inspire Record 188805 DOI 10.17182/hepdata.20536

Using the CLEO detector at the Cornell Electron Storage Ring, the authors have measured the leptonic branching fractions, Bμμ, of the ϒ(1S), ϒ(2S), and ϒ(3S) to be 2.7±0.3±0.3%, 1.9±1.3±0.5%, and 3.3±1.3±0.7%, respectively. Combining these values of Bμμ with previous measurements of the leptonic widths of these resonances, the authors find the total widths of the ϒ(1S), ϒ(2S), and ϒ(3S) to be 48±4±4, 27±17±6, and 13±4±3 keV.

1 data table
Table 1

No description provided.


The Reactions $pp \to pp$ $\pi^+ \pi^-, K^+ p \to K^+ p$ $\pi^+ \pi^-$, $\pi^+ p \to \pi^+ p$ $\pi^+ \pi^-$ and $\pi^- p \to \pi^+ \pi^-$ at 147 GeV/c

Brick, D.H. ; Rudnicka, H. ; Shapiro, A.M. ; et al.
Z.Phys.C 19 (1983) 1-9, 1983.
Inspire Record 194363 DOI 10.17182/hepdata.16321

We have studied the reactionspp→ppπ+π-,K+p→K+pπ+π−π, π+p→ π+,pπ+π− and π−p →π+π− at 147 GeV/c using the 30-inch Fermilab hybrid system. All four reactions were detected with the same apparatus and analyzed in the same way. The energy dependence of the channel cross section was found to beAp−0.6+B for thepp reaction andAp−1+B for the other three. About 90% of the cross section at 147 GeV/c can be accounted for by either beam or target diffraction. Some of the remaining cross section may come from double Pomeron exchange reactions which we tried to isolate. We have tested the hypothesis of a factorizable Pomeron and our data indicates a violation of this hypothesis. We show that the 3π mass enhancement in the mass region 1.2–1.4 GeV is diffractively produced in the π± beam reactions. Fourprong, four-constraint and six-prong, four-constraint cross sections are reported.

6 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

CROSS SECTIONS FOR DIFFRACTION DISSOCIATION OF BEAM. FEYNMAN X OF OUTGOING PROTON <-0.96.

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Polarization of $\Xi^0$ and $\Lambda$ Hyperons Produced by 400 GEV/c Protons

Heller, Kenneth J. ; Cox, P.T. ; Dworkin, J. ; et al.
Phys.Rev.Lett. 51 (1983) 2025-2028, 1983.
Inspire Record 196831 DOI 10.17182/hepdata.20515

The polarization of Ξ0 and Λ hyperons produced by 400-GeV protons interacting with a beryllium target has been measured in the projectile fragmentation region. The Ξ0 polarization agrees in sign, magnitude, and kinematic behavior with that of Λ. The target dependence of these Ξ0 and Λ polarizations was also investigated with use of Cu and Pb targets.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Resonance Production in Diffractive $\pi^- N \to K^0_s K^0_s \pi^- N^{\prime}$ at 200-GeV/c

Chen, T.Y. ; Jenkins, E.W. ; Johnson, K.J. ; et al.
Phys.Rev.D 28 (1983) 2304, 1983.
Inspire Record 182627 DOI 10.17182/hepdata.23787

The reaction π−N→KS0KS0π−N′ at 200 GeV/c has been observed with a sensitivity of 450±150 events/μb. The KS0KS0π− system exhibits substantial K*−(890)K0 production. Also produced are f0(1270)π−, f′(1515)π−, and K*−(1430)K0 final states. These resonances occur predominantly at threshold. The diffractive KS0KS0π− cross section is 3.4±1.1 μb. An enhancement near the A3−(1680) is observed in the KS0KS0π− invariant-mass distribution.

2 data tables
Table 1

No description provided.

Table 2

EVIDENCE FOR A3 MESON SEEN.


Inclusive $\phi$ Meson Production in $K^-$, $\bar{p}$ and $p$ Be Interactions at 100-{GeV}/$c$

The ACCMOR collaboration Daum, C. ; Hertzberger, L.O. ; Hoogland, W. ; et al.
Z.Phys.C 18 (1983) 1, 1983.
Inspire Record 183362 DOI 10.17182/hepdata.16360

Inclusive ϕ-meson production has been measured for 100 GeV/cK−,\(\bar p\) andp incident on a Be target. Differential cross sectionsdσ/dxF anddσ/dp⊥2 are presented in the interval 0.075<xF<0.225 and 0<p⊥<1 GeV/c respectively. The shape of thedσ/dxF distributions agrees with predictions from a quark fusion model. Comparison with cross sections measured on a hydrogen target in the samexF andp⊥ range suggest a linearA-dependence fromA=1 toA=9.

1 data table
Table 1

No description provided.


Charm $D$ Meson Production in 360-{GeV} $\pi^- p$ Interactions: Evidence for Leading Quarks

The LEBC-EHS collaboration Aguilar-Benitez, M. ; Allison, W.W.M. ; Bagnaia, P. ; et al.
Phys.Lett.B 123 (1983) 98-102, 1983.
Inspire Record 182456 DOI 10.17182/hepdata.30715

Charm D-meson production in 360 GeV π − p interactions has been studied using the high-resolution hydrogen bubble chamber LEBC and the European Hybrid Spectrometer. The data show evidence for leading quark effects both in the number of D-meson types and in the Feynman x distributions. The production cross section is of the form d 2 δ d x d p T 2 ∞(1-x) n exp (-ap T 2 ) with n = 2.8±0.8 and a = 1.1±0.3 (GeV/ c ) −2 . The x distribution is, however, compatible with the presence of both central ( n = 6) and leading (n = 1) D / D production. The fraction of D-messons in the leading component is estimated to be ≈30%. The rapidity gap between members of reconstructed charm pairs is small compared to the available rapidity range. The inclusive cross section for single D-messons in the forward direction is: δ(D/ D )=(40 8 +15 )μ b ( for x>0) .

1 data table
Table 1

No description provided.


Experimental Study of the Nucleon Structure Functions and of the Gluon Distribution from Charged Current Neutrino and anti-neutrinos Interactions

The CHARM collaboration Bergsma, F. ; Dorenbosch, J. ; Jonker, M. ; et al.
Phys.Lett.B 123 (1983) 269, 1983.
Inspire Record 181908 DOI 10.17182/hepdata.30729

Inclusive neutrino and antineutrino charged current interactions were studied in the CHARM detector exposed to neutrino and antineutrino Wide Band Beams of the CERN 400 GeV SPS. The x and Q 2 dependence of the structure functions F 2 and xF 3 and of the antiquark momentum distribution q were determined. The data have been interpreted in terms of QCD theory using the Furmanski-Petronzio method. In this way we have determined Λ LO = [190 −40 +70 ( stat ) ± 70 ( syst .)] MeV and the structure functions of quarks and gluons without specific assumptions on their analytic dependence. The results agree with previous experiments which relied on model assumptions in the analysis. We conclude that the model independent simultaneous analysis of the xF 3 , F 2 , q structure functions gives a more reliable determination of the gluon distribution in the nucleon.

2 data tables
Table 1

No description provided.

Table 2

HERE THE QBAR IS D2(SIG(ANU))/DX/DY - (1-Y)**2*D2(SIG(NU))/DX/DY.


NEW RESULTS ON KAON - PROTON ELASTIC SCATTERING AT LARGE MOMENTUM TRANSFERS

The Annecy(LAPP)-CERN-Bohr Inst-Genoa-Oslo-London collaboration Asad, Z. ; Baglin, C. ; Bock, R. ; et al.
Phys.Lett.B 123 (1983) 265-268, 1983.
Inspire Record 182422 DOI 10.17182/hepdata.30730

Measurements of the K - p and K + p elastic differential cross sections at 20 and 50 GeV/ c , respectively, have been made in the momentum transfer range 0.7 < ∥ t ∥ < 8.0 GeV/ c .

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Charm $D$ Meson Production in 360-{GeV}/$c p p$ Interactions: Comparison With $\pi^- p$ at the Same Energy

The LEBC-EHS collaboration Aguilar-Benitez, M. ; Allison, W.W.M. ; Bagnaia, P. ; et al.
Phys.Lett.B 123 (1983) 103-107, 1983.
Inspire Record 182457 DOI 10.17182/hepdata.30746

Charm D-meson production in 360 GeV pp interactions has been studied using the high-resolution hydrogen bubble chamber LEBC and the European Hybrid Spectrometer. D-mesons are produced with a differential cross section of the form d 2 σ d x d p T 2 δ(1-x) n exp (-ap T 2 ) , with n =1.8± 0.8 and a =1.1±0.03 GeV/ c −2 for the Feynman x and Transverse momentum p T behaviour. The inclusive partle prticle crossssection for D and D̄;measured to be: σ(D/ D ̄ ) = (56 −12 25 μ b (for all x ). The Λ c D ̄ cross section can be estimated to be ≈20 μ b. No strong correlation is observed between DD̄ pairs. The results are compared with results from a study of D-meaon production in 360 GeV/ c π − p interactions also using LEBC-EHS.

1 data table
Table 1

No description provided.


Investigation of Two Photon Final States in $e^+ e^-$ Annihilation at $\sqrt{s}=34$.2-{GeV}

The CELLO collaboration Behrend, H.J. ; Chen, C. ; Fenner, H. ; et al.
Phys.Lett.B 123 (1983) 127-132, 1983.
Inspire Record 182585 DOI 10.17182/hepdata.30780

Two photon final states in e + e − annihilation have been analyzed at CM energies around 34 GeV. Good agreement with QED is observed. Lower limits for the QED cutoff parameters of Λ + > 59 GeV and Λ - > 44 GeV are determined. A search for two photons with missing energy yields an upper limit for the production of neutral particles which decay into a photon and a non-interacting particle. Constraints on the mass and the coupling strength of supersymmetric photinos are discussed.

2 data tables
Table 1

Cross section for ABS(cos(theta)) <0.85.

Table 2

No description provided.