Armstrong, D.S.
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rivet Analysis
Observation of Tensor and Scalar Mesons Produced in $e^+ e^-$ Annihilation at 29-{GeV}

Abachi, S. ; Baringer, Philip S. ; Bylsma, B.G. ; et al.
Phys.Rev.Lett. 57 (1986) 1990, 1986.
Inspire Record 18688 DOI 10.17182/hepdata.20227

The production of the tensor mesons f0(1270) and K*0(1430) and the scalar meson S(975) has been observed in e+e− annihilation at 29 GeV center-of-mass energy by use of data obtained with the high-resolution spectrometer at the SLAC e+e− storage ring PEP. The mean multiplicities for meson momenta greater than 1450 MeV/c are 〈nf0〉=0.11±0.04, 〈nK*0(1430)〉=0.10±0.06, and 〈nS〉=0.05±0.02 per hadronic event. The fragmentation functions of the tensor mesons are in good agreement with the predictions of the Webber cluster model. The data are consistent with a predominant strange-quark content on the S meson.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Asymmetry in the Angular Distribution of Inclusive $\Lambda$ Baryons From $e^+ e^-$ Annihilations at $\sqrt{s}=29$-{GeV}

Abachi, S. ; Baringer, Philip S. ; Bylsma, B.G. ; et al.
Phys.Lett.B 181 (1986) 403-406, 1986.
Inspire Record 18955 DOI 10.17182/hepdata.30215

A forward-backward asymmetry A , consistent with that expected from the γ − Z 0 interference term in the process e + e − → q q , is observed in the laboratory production angular distribution of high-momentum ∧ baryons. The data were collected with the High Resolution Spectrometer at PEP. The asymmetry for ∧ baryons with fractional energy z= 2E s greater than 0.3 is A = (−23± 8 plusmn ; 2)%.

2 data tables
Table 1

No description provided.

Table 2

Data read from graph.


Charged Particle Multiplicity Distributions in $e^+ e^-$ Annihilation at 29-{GeV}: A Comparison With Hadronic Data

Derrick, M. ; Gan, K.K. ; Kooijman, P. ; et al.
Z.Phys.C 35 (1987) 323, 1987.
Inspire Record 235873 DOI 10.17182/hepdata.15773

The charged particle multiplicity distributions for two-jet events ine+e− annihilation at 29 GeV have been measured using the High Resolution Spectrometer at PEP. A Poisson distribution describes the data for both the complete event and for the single jets. In addition, no correlation is observed between the multiplicities in the two jets of an event. For fixed values of the prong number of the complete event, the multiplicity sharing between the two jets is in good agreement with a binomial distribution. The rapidity gap distribution is exponential with a slope equal to the mean rapidity density. These observations, which are consistent with a picture of independent emission of single particles, are contrasted to the results from soft hadronic collisions and conclusions are drawn about the nature of clusters.

4 data tables
Table 1

Charged Particle Multiplicity distributions for single jet and whole event from the two jet sample. The numerical values are given in the paper Derrick et al, PR D34 (86) 3304, and are coded in this database as (<a href=http://durpdg.dur.ac.uk/scripts/reacsearch.csh/TESTREAC/red+1437> RED = 1437 </a>).

Table 2

Single Jet Mean Multiplicities.

Table 3

Total event charged multiplicities.

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Measurement of Anti-neutron Proton Total and Annihilation Cross-sections From 100-{MeV}/c to 500-{MeV}/c

The BROOKHAVEN-HOUSTON-PENNSYLVANIA STATE-RICE collaboration Armstrong, T. ; Chu, C. ; Clement, J. ; et al.
Phys.Rev.D 36 (1987) 659-673, 1987.
Inspire Record 253128 DOI 10.17182/hepdata.26943

Total and annihilation n¯p cross sections from 100 to 500 MeV/c are reported, the first such measurements with good statistics in this momentum range. These cross sections are well represented by A+B/p, where p is the incident antineutron momentum, and are in agreement with previous n¯p and p¯n measurements. A comparison of these cross sections with phenomenological potential model calculations is good overall. However, the microscopic quark model gives unsatisfactory predictions. The agreement between previous p¯p annihilation cross sections and n¯p cross sections above 300 MeV/c is excellent. The total n¯p cross section is lower than the total p¯p cross section in this momentum range. Both of these types of behavior are predicted by potential models. The anticipated availability of future p¯p data below 300 MeV/c should indicate whether these trends continue at lower momenta.

1 data table
Table 1

No description provided.


Measurement of inclusive cross sections for production of cumulative protons in pi-, K-, and anti-p interactions in Be at 40-GeV/c.

Antipov, Yu.M. ; Batarin, V.A. ; Bezzubov, V.A. ; et al.
Sov.J.Nucl.Phys. 48 (1988) 297-300, 1988.
Inspire Record 254775 DOI 10.17182/hepdata.40801

None

1 data table
Table 1

No description provided.


Version 2
rivet Analysis
Production of Strange Baryons in $e^+ e^-$ Annihilations at 29-{GeV}

Abachi, S. ; Baringer, Philip S. ; Bylsma, B.G. ; et al.
Phys.Rev.Lett. 58 (1987) 2627, 1987.
Inspire Record 246162 DOI 10.17182/hepdata.20154

The production of strange baryons Σ± (1385) and Ξ− has been observed in e+e− annihilations at 29 GeV center-of-mass energy, by use of data obtained with the High Resolution Spectrometer at the SLAC storage ring PEP. The total mean multiplicities are measured to be 〈nΣ±(1385)〉=0.033±0.006±0.005 and &〉=0.016±0.004 ±0.004 per hadronic event. The results are in good agreement with the Lund string model.

4 data tables
Table 1

Lund model extrapolation to full x range.

Table 2

Lund model extrapolation to full x range.

Table 3

No description provided.

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ELASTIC SCATTERING OF pi- AND K- MESONS ON PROTONS AT 43-GeV/c MOMENTUM

The SIGMA-AYaKS & Dubna-Serpukhov-Tbilisi collaborations Antipov, Yu.M. ; Batarin, V.A. ; Bezzubov, V.A. ; et al.
Sov.J.Nucl.Phys. 48 (1988) 85, 1988.
Inspire Record 253399 DOI 10.17182/hepdata.38881

None

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

FROM EXPONENTIAL FIT OF D(SIG)/D(T) IN RANGE 0. < ABS(T) < 1. GEV.


Charged $K^*$ Production in $e^+ e^-$ Annihilations at 29-{GeV}

Abachi, S. ; Baringer, Philip S. ; Bylsma, B.G. ; et al.
Phys.Lett.B 199 (1987) 151-154, 1987.
Inspire Record 22433 DOI 10.17182/hepdata.6521

We report a measurement of the charged K ∗ (892) production in e + e − annihilations at 29 GeV center-of-mass energy. The 300 pb −1 data sample used for this analysis is obtained with the High Resolution Spectrometer at the SLAC storage ring PEP. The total mean multiplicity is measured to be 〈n K ∗± (892) 〉=0.62±0.045±0.04 per hadronic event. Evidence is also given for the production of a charged K 2 ∗ (1430) tensor meson.

6 data tables
Table 1

Extrapolation to full x-range using Lund model.

Table 2

Data requested from authors.

Table 3

Extrapolation to full x-range usisng fragmentation friction predicted by the Webber cluster model.

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Measurement of the imaginary part of the I=1 $\bar{N} N$ S‐wave scattering length

Mutchler, G.S. ; Clement, J. ; Kruk, J. ; et al.
Phys.Rev.D 38 (1988) 742-753, 1988.
Inspire Record 268866 DOI 10.17182/hepdata.23244

The survival time spectrum of slow antineutrons produced in a LH2 target has been measured. From these data the imaginary part of the I=1 spin averaged S‐wave antineutron proton scattering length has been deduced to be Im a1= −0.83±0.07 fm. The result lies within the range of values calculated from current potential models.

1 data table
Table 1

THE VALUE AT PLAB = 0. HAVE BEEN OBTAINED BY EXTRAPOLATION.


A Measurement of the S and $P$ Wave Content of Anti-proton Annihilation at Rest Into Two Pions in Liquid Deuterium

The Athens-Irvine-Karlsruhe-New Mexico-Pennsylvania State collaboration Angelopoulos, A. ; Apostolakis, A. ; Armstrong, T.A. ; et al.
Phys.Lett.B 212 (1988) 129-132, 1988.
Inspire Record 269695 DOI 10.17182/hepdata.29910

Based on our measurement of the ratio f(π − π 0 p ) f(π + π − n ) =2.07±0.05 for antiproton annihilation at rest in liquid deuterium, we find that S-wave annihilation of the antiproton on the proton or neutron into ππ is dominant. We quote a 95% confidence level upper limit of 8% for P-wave annihilation into ππ.

1 data table
Table 1

No description provided.