Hoffnagle, J.
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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.


Observation of a Dependence in Koba-nielsen-olesen Scaling Distributions for High-energy Hadron Nucleus Interactions

Biswas, N.N. ; Ting, S.J.Y. ; Mattingly, M.C.K. ; et al.
Phys.Rev.D 33 (1986) 3167-3171, 1986.
Inspire Record 233004 DOI 10.17182/hepdata.23515

Experimental multiplicity distributions scaled in the Koba-Nielsen-Olesen (KNO) form for hadron-nucleus interactions show clear deviations from the scaling distribution observed for hadron-hadron interactions. The deviations become larger as A increases. Our data can be described by a model which invokes the hypothesis that KNO scaling is valid for hadron-nucleus interactions at a fixed impact parameter. In this model, the A dependence of the multiplicity distributions results from the convolution of scatterings at various impact parameters.

6 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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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.


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 THE S MESON IN ANTI-PROTON PROTON INTERACTIONS

Fickinger, W. ; Marino, R. ; Robinson, D.K. ; et al.
Phys.Rev.D 34 (1986) 3332-3342, 1986.
Inspire Record 239036 DOI 10.17182/hepdata.26472

The interaction between antiprotons and protons has been studied in the range 1910 to 1990 MeV center-of-mass energy in a drift-chamber experiment at the Brookhaven Alternating Gradient Synchrotron. The total cross section has been determined at eleven different incident momenta, and the elastic cross section between 8 and 30 deg in the laboratory has been measured with an energy resolution of about 5 MeV. The cross section for annihilation into charged mesons has also been measured, with the same resolution. There is no evidence in any of these channels for the existence of a narrow resonance.

3 data tables
Table 1

Data are for total sample with nuclear physics calculation as described in the paper.

Table 2

Partial elastic cross sections.

Table 3

Partial annihilation cross sections.


rivet Analysis
PION AND KAON MULTIPLICITIES IN HEAVY QUARK JETS FROM e+ e- ANNIHILATION AT 29-GeV

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Avery, R.E. ; et al.
Phys.Lett.B 184 (1987) 299-304, 1987.
Inspire Record 235694 DOI 10.17182/hepdata.30210

The multiplicities per event of π ± and K ± are measured separately for e + e - annihilation into c c , b b , and light quark pairs at E cm=29 GeV. The K ± multiplicity is higher for heavy quark events than for light quark events. The π ± multiplicity and the π ± scaled differential cross section at low x = E beam/ E beam are found to be higher for b b events than for other events.

5 data tables
Table 1

Numerical values requested from authors. Data given separately for (b bbar), (c cbar) and light quark jets.

Table 2

Measured multiplicities for (b bbar) jets.

Table 3

Measured multiplicities for (c cbar) jets.

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A SEARCH FOR NARROW STATES IN ANTI-NEUTRON PROTON TOTAL AND ANNIHILATION CROSS-SECTIONS NEAR ANTI-N N THRESHOLD

Armstrong, T. ; Chu, C. ; Clement, J.C. ; et al.
Phys.Lett.B 175 (1986) 383-386, 1986.
Inspire Record 236704 DOI 10.17182/hepdata.30241

The n̄p total and annihilation cross section have been measured from near N̄N threshold (1880 MeV) to 1940 MeV with RMS resolution ranging from 0.08 MeV (1880 MeV) to 6.7 MeV (1940 MeV). No significant narrow meson structures were seen, with 90% CL upper limits of 40–180 mb-MeV on σΓ for states with width less than our resolution. Combined with increasing unitarity bounds on σ as one approaches threshold, these limits confine widths of possible predicted states below 1900 MeV to less than ∼ 1 MeV.

1 data table
Table 1

No description provided.


High-energy Photoproduction of Large Transverse Momentum $\pi^0$ Mesons: A Quantitative Test of {QCD}

The NA14 collaboration Auge, E. ; Barate, R. ; Bloch, D. ; et al.
Phys.Lett.B 168 (1986) 163-169, 1986.
Inspire Record 227057 DOI 10.17182/hepdata.30278

The first results on inclusive photoproduction of π 0 at transverse momenta up to 4 GeV/ c , using incident γ energies between 50 and 150 GeV are presented. A comparison is made with inclusive π 0 production obtained, in the same experiment, with incident π − . Using the π − data to parametrize the hadronic behaviour of the photon, significant differences are observed in quantitative agreement with QCD Compton scattering and corrections thereof.

2 data tables
Table 1

FC,IC,BC REFER TO FORWARD,INTERMEDIATE AND BACKWARD CALORIMETERS.

Table 2

FC,IC,BC REFER TO FORWARD,INTERMEDIATE AND BACKWARD CALORIMETERS.


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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Rapidity Dependence of the Charged Particle Multiplicity Distributions in e+ e- Annihilation at 29-GeV

Derrick, M. ; Gan, K.K. ; Kooijman, P. ; et al.
Phys.Lett.B 168 (1986) 299-304, 1986.
Inspire Record 17794 DOI 10.17182/hepdata.30277

The charged particle multiplicity distribution for e + e − annihilations at s = 29 GeV has been measured using the High Resolution Spectrometer at PEP. The multiplicity distribution, expressed as a function of the mean, shows KNO scaling when compared to e + e − data at other energies. Multiplicity distributions for particles selected in different central rapidity spans are presented. All of these are well presented by the Negative binomial distribution. As the rapidity span is narrowed, the distributions become broader and approach a constant value of the parameter k .

12 data tables
Table 1

KNO charged multiplicity distributions for the Inclusive Data Sample. The numerical values are calculated from the multiplicity distributions given in Derrick et al., PR D34,3304.

Table 2

Folded rapidity distribution measured along the thrust axis of the event. Errors are dominated by systematics. All charged particles are assigned the pion mass.

Table 3

KNO charged multiplicity distribution for the Two Jet Data Sample. The numerical values are calculated from the multiplicity distributions given in Derrick et al., PR D34,3304.

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