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Backward $K^{*0}$ Production in $\pi^- p \to \Lambda^0 K^+ \pi^-$ Reaction at 9-{GeV}/$c$ and 12-{GeV}/$c$

Ferrer, A. ; Treille, D. ; Rivet, P. ; et al.
Nucl.Phys.B 178 (1981) 373-391, 1981.
Inspire Record 153782 DOI 10.17182/hepdata.34397

We have analysed about 85 000 fast Λ 0 events, obtained in a fast proton triggered experiment performed at the CERN-Ω spectrometer at 9 and 12 GeV/ c incident π − beam. Nearly 2500 Λ 0 K + π − events have been isolated. We find strong production of quasi-two-body processes Λ 0 K ∗0 and ∑ ∗− K + consistent with u -channel hyperon exchange. Results on Λ 0 polarization, K ∗0 decay parameters and differential cross sections are given for Λ 0 K ∗0 (892) and Λ 0 K ∗0 (1430) final states. A comparison is made with the associated backward Λ 0 (1520) K ∗0 production seen in the four-prong reaction π − p→pK − K + π − obtained in the same experiment.

8 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

EXPONENTIAL FIT TO DN/DU.

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Polarization in Charge Exchange Reaction $\pi^- p \to \pi^0 n$ in Small Momentum Transfer Range at 40-{GeV}/$c$

Apokin, V.D. ; Avvakumov, I.A. ; Bagaturiya, Yu.Sh. ; et al.
Experientia Suppl. 38 (1981) 554, 1981.
Inspire Record 154047 DOI 10.17182/hepdata.11048

None

2 data tables
Table 1

AVERAGE TARGET POLARIZATION WAS 76 +- 3 PCT.

Table 2

No description provided.


rivet Analysis
Total Cross-section for Hadron Production by $e^+ e^-$ Annihilation Between 9.4-{GeV} and 9.5-{GeV}

The DESY-Hamburg-Heidelberg-Munich collaboration Bock, P. ; Heinzelmann, G. ; Pietrzyk, B. ; et al.
Z.Phys.C 6 (1980) 125, 1980.
Inspire Record 153896 DOI 10.17182/hepdata.14364

The total cross section fore+e− annihilation into hadrons for center of mass energies from 9.4 to 9.5 GeV has been measured with the nonmagnetic DESY-Heidelberg detector at DORIS. A value ofR=σhad/σµµ=3.8±0.7 for the continuum region around the Υ (9.46) resonance has been determined. The ratioΓeeΓhad/Γtot of electronic, hadronic and total widths has been reevaluated to be (1.00±0.23) keV for the Υ resonance and (0.37±0.16) keV for the Υ′. In addition, a search for directly produced pohotons from Υ decays of the type Υ→γ+gluon+gluon has been performed. The Υ decay into muon pairs has also been searched for.

1 data table
Table 1

TOTAL CROSS SECTION FOR THE CONTINUUM REGIONS AROUND THE UPSI(9460)0 AND UPSI(10020)0 RESONANCES.


Photoproduction of $\pi \Delta(1232)$ From Hydrogen in the Energy Range 2.4-{GeV} to 4.8-{GeV}

The LAMP2 Group collaboration Barber, D.P. ; Dainton, J.B. ; Lee, L.C.Y. ; et al.
Z.Phys.C 6 (1980) 93, 1980.
Inspire Record 153944 DOI 10.17182/hepdata.14328

We present differential cross sections andΔ++ spin density matrix elements for the photoproduction processγp→π−Δ++ and differential cross sections for the processγp→π+Δ0. The incident photon energy dependence is studied and a comparison is made with previous experiments and with the predictions of a theoretical model.

5 data tables
Table 1

DIFFERENTIAL CROSS SECTION AVERAGED OVER WHOLE ENERGY RANGE.

Table 2

DIFFERENTIAL CROSS SECTION AVERAGED OVER WHOLE ENERGY RANGE.

Table 3

DIFFERENTIAL CROSS SECTION FOR DIFFERENT ENERGY RANGES.

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Study of the Reactions $\pi^- p \to K^0 \Lambda$ and $\pi^- p \to K^0 \Sigma^0$ at 3.95-{GeV}/$c$

The CERN-College de France-Madrid-Stockholm collaboration Loverre, P.F. ; Armenteros, R. ; Dionisi, C. ; et al.
Z.Phys.C 6 (1980) 283, 1980.
Inspire Record 153918 DOI 10.17182/hepdata.14374

The reactions π−p→K0Λ,K0Σ0 are studied at an incident momentum of 3.95 GeV/c using data from a high statistics bubble chamber experiment corresponding to ∼90 events/μb. The differential cross sections and hyperon polarizations are presented and compared with existing data from earlier electronic experiments. The data in the forward hemisphere are used to perform an amplitude analysis of the 0−1/2+→0−1/2+ hypercharge exchange processes.

9 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Study of the Reactions $\pi^- p \to K^0 \Sigma^0(1385)$ and $\pi^- p \to K^+ \Sigma^-(1385)$ at 3.95-{GeV}/$c$

The CERN-College de France-Madrid-Stockholm collaboration Aguilar-Benitez, M. ; Albajar, M.C. ; Ferrando, A. ; et al.
Z.Phys.C 6 (1980) 109-123, 1980.
Inspire Record 153921 DOI 10.17182/hepdata.14369

The reactionsπ−p→K0∑0(1385) andπ−p→K+∑−(1385) are studied at an incident momentum of 3.95 GeV/c using data from a high statistics bubble chamber experiment corresponding to approximately 90 events/μb. The total and differential cross sections and the density matrix elements of the Σ(1385) are presented. The results are compared with those obtained for the related processesπpp→K+∑+(1385) and\(K^ -p \to \pi ^ \mp\sum ^ \pm(1385)\) in this energy range. Evidence is presented for the existence of production mechanisms with exotic exchanges in thet channel.

16 data tables
Table 1

FROM THE CHANNEL PI- P --> LAMBDA K0 PI0 WHICH HAS A CROSS SECTION OF 72 +- 4 MUB.

Table 2

FROM THE CHANNEL PI- P --> LAMBDA K+ PI- WHICH HAS A CROSS SECTION OF 79 +- 3 MUB.

Table 3

FORWARD CROSS SECTION.

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Strangeness Exchange in the Photoproduction of $K^+ \Lambda$ (1520) Between 2.8-{GeV} and 4.8-{GeV}

Barber, D.P. ; Dainton, J.B. ; Lee, L.C.Y. ; et al.
Z.Phys.C 7 (1980) 17, 1980.
Inspire Record 153887 DOI 10.17182/hepdata.14096

A tagged photon beam (2.8<Eγ<4.8 GeV) and multiparticle spectrometer have been used to study the photoproduction in hydrogen ofK+Λ(1520). Precise values for the mass and width of the Λ(1520) are given. The total cross-section is found to fall with increasing photon energy like (6.5±0.7)Eγ−(2.1±0.2) μb. The differential cross sectiondσ/dt indicates peripheral forward production and exhibits no evidence for shrinkage when compared with higher energy data. The Λ(1520) spin density matrix shows thatK exchange alone cannot account for the production mechanism. The reaction is found to resemble the process γp→K+ Λ(1115) in all measurable respects.

3 data tables
Table 1

FITTED CROSS SECTION ENERGY DEPENDENCE IS SIG = (6.7 +- 0.7 MUB*GEV**2) * P**(-2.1 +- 0.2), INCLUDING HIGHER ENERGY DATA.

Table 2

EXPONENTIAL SLOPE IS 6.1 +- 2.0 GEV**-2 FOR -T = 0.2 TO 0.7 GEV**2.

Table 3

No description provided.


Total Width and Leptonic Branching Ratio of the $\Upsilon$ (9.46)

The LENA collaboration Niczyporuk, B. ; Zeludziewicz, T. ; Chen, K.W. ; et al.
Phys.Rev.Lett. 46 (1981) 92, 1981.
Inspire Record 153813 DOI 10.17182/hepdata.20644

With use of the LENA detector at the DORIS e+e− storage ring, the hadronic cross section and the μ-pair decay branching ratio of the ϒ(9.46) resonance have been measured. Γee=1.23±0.10 (±0.14) keV, Bμμ=[3.5±1.4 (±0.4)]%, and Γtot=35−10+25 ({+9}{−7}) keV have been obtained. The first set of errors gives the statistical uncertainty. The numbers in parentheses represent systematic errors arising from the uncertainty in the total hadronic cross section.

1 data table
Table 1

No description provided.


INCLUSIVE MUON PRODUCTION AT PETRA ENERGIES

The Pluto collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.
Phys.Rev.Lett. 45 (1980) 1533-1537, 1980.
Inspire Record 153812 DOI 10.17182/hepdata.20692

In this Letter, a measurement of inclusive muon production (pμ>2 GeV/c) in e+e− annihilation into hadrons at center-of-mass energies from s=12 to 31.6 GeV is reported. The results agree with the expected semileptonic decays from charmed and bottom mesons.

2 data tables
Table 1

MUONS PER HADRONIC EVENT.

Table 2

INVARIANT CROSS SECTION, ASSUMING HADRONIC CROSS SECTION HAS R VALUE OF 3.9 +- 0.5.


Observation of the Upsilon''' at CESR

Finocchiaro, G. ; Giannini, G. ; Lee-Franzini, Juliet ; et al.
Phys.Rev.Lett. 45 (1980) 222, 1980.
Inspire Record 9427 DOI 10.17182/hepdata.20691

During an energy scan at the Cornell Electron Storage Ring, with use of the Columbia University-Stony Brook NaI detector, an enhancement in σ(e+e−→hadrons) is observed at center-of-mass energy ∼10.55 GeV. The mass and leptonic width of this state (ϒ′′′) suggest that it is the 4S13 bound state of the b quark and its antiquark. After applying to the data a cut in a (pseudo) thrust variable, the natural width is measured to be Γ=12.6±6.0 MeV, indicating that the ϒ′′′ is above the threshold for BB¯ production.

1 data table
Table 1

VISIBLE TOTAL HADRONIC CROSS SECTION FOR FIRST, THIRD AND FOURTH UPSILONS.