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Measurement of the Spin Correlation Parameters A(ll) and A(sl) for the Reaction $P P \to D \pi^+$ in the Energy Region 500-{MeV} - 800-{MeV}

Barlow, D.B. ; Saha, A. ; Seth, K.K. ; et al.

Phys.Rev.C 37 (1988) 1977-1986, 1988.

Inspire Record 242361 DOI 10.17182/hepdata.26282

Angular distributions of the spin-correlation parameters Asl and All for the reaction pp→π+d have been measured at pion center-of-mass angles 40°≤θπ+*≤130° at incident energies of 500, 650, and 800 MeV. Additional measurements of All were made at 600, 700, and 750 MeV. The results of the experiment are compared with the predictions of several unified coupled-channel calculations and partial-wave analyses. While the latest partial-wave analyses were found to fit the data reasonably well, all except one of the various model predictions not only do not fit the data well, but also tend to be in disagreement with each other. The data show no clear sign of a need for proposed dibaryon resonances.

9 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

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Inclusive $\Lambda^0$ Polarization in Proton Nucleus Collisions at 12-{GeV}

Abe, F. ; Hara, K. ; Kim, S. ; et al.

Phys.Rev.D 34 (1986) 1950-1959, 1986.

Inspire Record 237791 DOI 10.17182/hepdata.23459

The polarization of Λ0 hyperons in inclusive production by 12-GeV protons on nuclei has been measured for beryllium, copper, and tungsten targets. Data are obtained at five production angles, 3.5°, 5.0°, 6.5°, 8.0°, and 9.5°, covering the kinematic range 0.26≤xF≤0.77 and 0.4≤pT≤1.5 GeV/c. The dependence of the polarization on target nuclei is investigated by statistical analyses of the data. The polarization at fixed pT increases roughly linearly with xF. The present results are compared with other work at higher energies in terms of the A dependence and the (xF,pT) dependence.

5 data tables

Table 1

No description provided.

Table 2

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Table 3

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Production of Xi0 and anti-Xi0 hyperons by 400-GeV Protons

Beretvas, A. ; Deck, L. ; Devlin, T. ; et al.

Phys.Rev.D 34 (1986) 53-74, 1986.

Inspire Record 233799 DOI 10.17182/hepdata.23426

Inclusive production cross sections have been measured for the processes p+A→Ξ0+X (A=Be, Cu, Pb) and for p+Be→Ξ¯0+X. Data were taken at angles of 0, 2, 3.5, 7.3, and 9.8 mrad between the incident 400-GeV proton beam and the outgoing hyperon beam. Production cross sections for Λ and Λ¯ production were measured at the same time. The A dependence of the Ξ0 cross sections is discussed, along with interpretations in terms of various models.

8 data tables

Table 1

No description provided.

Table 2

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Table 3

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Measurements of Production Polarization and Decay Asymmetry for $\Xi^-$ Hyperons

Rameika, R. ; Beretvas, A. ; Deck, L. ; et al.

Phys.Rev.D 33 (1986) 3172-3179, 1986.

Inspire Record 233005 DOI 10.17182/hepdata.23517

The polarization of Ξ− hyperons produced by 400-GeV protons in the reaction p+Be→Ξ−+X has been measured as a function of momentum at two production angles. The average polarization for the full sample (192 110 events) was -0.108±0.007. Comparisons are made with polarization measurements for other hyperons produced under similar conditions. From the same data, αΛαΞ was measured to be -0.303±0.004±0.004, where αΛ is the asymmetry parameter in the decay Λ→pπ−, αΞ is the asymmetry parameter in the decay Ξ−→Λπ−, and the uncertainties are statistical and systematic, respectively. This yields αΞ=-0.472±0.006±0.011, where the systematic uncertainty is dominated by the uncertainty in αΛ. An updated test of the ΔI=1/2 rule in Ξ decay is presented.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

Prompt Electron Production From Delco at {PEP}

The DELCO collaboration Pal, T. ; Atwood, W.B. ; Barish, B.C. ; et al.

Phys.Rev.D 33 (1986) 2708, 1986.

Inspire Record 226886 DOI 10.17182/hepdata.23516

We report final results on prompt electron production in hadronic events from e+e− annihilations at √s =29 GeV, obtained with the DELCO detector at the SLAC storage ring PEP. We find the semielectronic branching ratios of charm and bottom quarks to be B(c→se+νe)=(11.6−0.9 +1.1)% and B(b→ce−ν¯e)=(14.9−1.9 +2.2)% respectively. These results, from the complete data set, are consistent with an earlier analysis of partial data and indicate hard fragmentation functions for both c and b quarks, with mean values 〈zc〉=0.59±0.04 and 〈zb〉=0.72±0.05. The errors indicated here are a combination of statistical and systematic uncertainties.

4 data tables

Table 1

Axis error includes +- 0.0/0.0 contribution (NOT GIVEN).

Table 2

Axis error includes +- 0.0/0.0 contribution (NOT GIVEN).

Table 3

Axis error includes +- 0.0/0.0 contribution (NOT GIVEN).

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Search for $D^*$ Production in Pion Nucleon Interactions

Fitch, V.L. ; Montag, A.D. ; Palestini, S. ; et al.

Phys.Rev.D 33 (1986) 1486-1487, 1986.

Inspire Record 232140 DOI 10.17182/hepdata.23545

Results are presented of a measurement of the production of D*+ (D*−) in 250-GeV/c π−N interactions. We observe 2.1±7.8 events corresponding to a charge-D* cross section σ(D*) of 0.4±1.5 μb/nucleon. When averaged with our previous measurement made at 200 GeV/c, the result is σ(D*)=2.3±1.0 μb/nucleon with (dσ/dx)‖x=0=4.6±2.0 μb.

3 data tables

Table 1

THIS DATA FROM PREVIOUS PUBLICATION : PRL 46, 761 (1981).

Table 2

No description provided.

Table 3

No description provided.

Observation of Double $\phi$ Meson Production in the Central Region for the Reactions $\pi^+ P \to \pi^+ (K^+ K^+ K^- K^-$) $P$ and $P P \to P (K^+ K^+ K^- K^-$) $P$ at 85-{GeV}/c

The ATHENS-BARI-BIRMINGHAM-CERN collaboration Armstrong, T.A. ; Bloodworth, I.J. ; Carney, J.N. ; et al.

Phys.Lett.B 166 (1986) 245-248, 1986.

Inspire Record 228698 DOI 10.17182/hepdata.30307

The reactions π + p → π + ( K + K + K − K − ) p and pp → p ( K + K + K − K − ) p in which the K + K + K − K − system is centrally produced have been studied at 85 GeV c . Evidence is found for φφ production. The relative rates for production of φφ , φK + K − and K + K + K − K − have been determined.

1 data table

Table 1

No description provided.

Neutral and Charged $D^*$ Production in 360-{GeV}/$c \pi^- p$ Interactions

The LEBC-EHS collaboration Aguilar-Benitez, M. ; Allison, W.W. ; Baland, J.F. ; et al.

Phys.Lett.B 169 (1986) 106-112, 1986.

Inspire Record 227059 DOI 10.17182/hepdata.30268

The first data on the production of D ∗ (2010) are presented as observed in π − -proton interactions at √ s = 27 GeV . It is found that D ∗ (2010) dominates the total charm D-meson production, without a significant non-central component.

4 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Lepton and pion pair production in γγ collisions measured near the threshold at DCI

Courau, A. ; Falvard, A. ; Haissinski, J. ; et al.

Nucl.Phys.B 271 (1986) 86800013 1-20, 1986.

Inspire Record 232808 DOI 10.17182/hepdata.38240

This paper reports a complete analysis of data taken at DCI to measure lepton and pion pair production close to the threshold in two-photon processes: e+e− → e+e−(e+e−, μ+μ−, π+π−). Preliminary results have been previously published including one-half of the total statistics. Final results presented here are in good agreement with QED for lepton pair production. The measured cross section for pion pair production is twice as large as that expected from Born terms only — a two standard deviation effect.

1 data table

Table 1

Normalised to number of observed electron pairs. Fully corrected for acceptance, radiative effects etc.

Inclusive Production of Hyperons and Anti-hyperons in $N$ C Collisions at an Energy of About 40-{GeV} (In Russian)

The BIS-2 collaboration Aleev, A.N. ; Arefev, V.A. ; Balandin, V.P. ; et al.

Yad.Fiz. 44 (1986) 661-670, 1986.

Inspire Record 239304 DOI 10.17182/hepdata.17456

None

4 data tables

Table 1

No description provided.

Table 2

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Table 3

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Measurement of the Spin Correlation Parameters A(ll) and A(sl) for the Reaction $P P \to D \pi^+$ in the Energy Region 500-{MeV} - 800-{MeV}

Inclusive $\Lambda^0$ Polarization in Proton Nucleus Collisions at 12-{GeV}

Production of Xi0 and anti-Xi0 hyperons by 400-GeV Protons

Measurements of Production Polarization and Decay Asymmetry for $\Xi^-$ Hyperons

Prompt Electron Production From Delco at {PEP}

Search for $D^*$ Production in Pion Nucleon Interactions

Observation of Double $\phi$ Meson Production in the Central Region for the Reactions $\pi^+ P \to \pi^+ (K^+ K^+ K^- K^-$) $P$ and $P P \to P (K^+ K^+ K^- K^-$) $P$ at 85-{GeV}/c

Neutral and Charged $D^*$ Production in 360-{GeV}/$c \pi^- p$ Interactions

Lepton and pion pair production in γγ collisions measured near the threshold at DCI

Inclusive Production of Hyperons and Anti-hyperons in $N$ C Collisions at an Energy of About 40-{GeV} (In Russian)