Morfin, J.
Phenomenology-HEP
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Measurements of r and a Search for Heavy Quark Production in e+ e- Annihilation at s**(1/2) = 50-GeV and 52-GeV

The AMY collaboration Sagawa, H. ; Mori, T. ; Abe, K. ; et al.
Phys.Rev.Lett. 60 (1988) 93, 1988.
Inspire Record 251270 DOI 10.17182/hepdata.20143

The ratio R of the cross section for e+e− annihilation into hadronic final states to the QED cross section for muon-pair production is measured to be 4.34±0.45±0.30 and 4.23±0.20±0.21 at c.m. energies of 50 and 52 GeV, respectively. From these values of R and an analysis of the event shapes we deduce a 95%-confidence-level upper limit for the production rate of new heavy charge +23e or −13e quarks to be 0.19 units of R.

1 data table
Table 1

No description provided.


COMPARISON OF THE PARTICLE FLOW IN q anti-q g AND q anti-q gamma EVENTS IN e+ e- ANNIHILATION

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Avery, R.E. ; et al.
Phys.Rev.Lett. 57 (1986) 945, 1986.
Inspire Record 230224 DOI 10.17182/hepdata.38183

We compare the particle flow in the event plane of three-jet qq¯g (quark-antiquark-gluon) events with the particle flow in radiative annihilation events qq¯γ (quark-antiquark-photon) for similar kinematic configurations. In the angular region between quark and antiquark jet, we find a significant decrease in particle density for qq¯g as compared to qq¯γ. This effect is predicted in QCD as a result of destructive interference between soft-gluon radiation from quark, antiquark, and hard gluon.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


LIMITS ON CHARM PRODUCTION IN HADRONIC INTERACTIONS NEAR THRESHOLD

Christenson, J.H. ; Hummel, E. ; Kreiter, G.A. ; et al.
Phys.Rev.Lett. 55 (1985) 154, 1985.
Inspire Record 16192 DOI 10.17182/hepdata.3274

We present the results of an experiment to search for associated charm production near threshold in 13-GeV/c π−p interactions. A large aperture PWC spectrometer was sensitive to the decay fragments of the forward-produced D*−’s expected from the two-body reactions π−+p→D*−+Λc+,Σc +,. . . . The missing baryon mass was determined from the vector momenta of the incident pion and the candidate D*−. No evidence for these reactions was found, which resulted in a 7-nb upper limit (95% confidence level) for each of the cross sections σ(π−p→D*−Λc+) and σ(π−p→D*−Σc+).

2 data tables
Table 1

Axis error includes +- 0.0/0.0 contribution (?////NOT GIVENDECAY-BR(BRN=D*(2010)- --> AD0 PI-,BR=64 IN PCT)//DECAY-BR(BRN=AD0 --> K+ PI-, BR=3 IN PCT)).

Table 2

No description provided.


Hyperon Production in $e^+ e^-$ Interactions in the $\Upsilon$ Region

The CLEO collaboration Alam, M.S. ; Csorna, S.E. ; Garren, L. ; et al.
Phys.Rev.Lett. 53 (1984) 24, 1984.
Inspire Record 200712 DOI 10.17182/hepdata.20410

We report measurements from the CLEO detector of the rate of Ξ and Λ production in e+e− interactions in the upsilon region. Hyperon production from the decay of the ϒ(1s) is compared with continuum e+e− data. The ratio of the production rates of Λ (and Λ―) to K0 (and K―0) on the ϒ(1s) is 0.21 ± 0.03, much larger than in the continuum, 0.07 ± 0.01. The ratios of the production rates of the Ξ and Λ are comparable, 0.10±0.02 [ϒ(1S)] and 0.07 ± 0.02 (continuum). We discuss some implications of the data for gluon and quark fragmentation models.

2 data tables
Table 1

CONTINUUM IS ECM 10.38 TO 10.64 GEV.

Table 2

No description provided.


Data on the Gross-llewellyn Smith Sum Rule as a Function of $q^2$

The Aachen-Bonn-CERN-Democritos-London-Oxford-Saclay collaboration Bolognese, T. ; Fritze, P. ; Morfin, J. ; et al.
Phys.Rev.Lett. 50 (1983) 224, 1983.
Inspire Record 178566 DOI 10.17182/hepdata.20544

Data are presented on the Gross-Llewellyn Smith sum rule obtained from combined narrow-band neon and Freon bubble-chamber neutrino-antineutrino experiments. Remarkably no significant deviation from the parton-model prediction for the sum rule is observed at very low values of q2≲1 GeV2. Limits on the effective QCD scale parameter Λ and on the magnitude of the twist-4 correction are set. The best fit, neglecting higher-twist contributions, gives Λ=92−36+20 MeV.

1 data table
Table 1

NACHTMANN MOMENT IS EVALUATED (IE TARGET MASS COEERCTIONS INCLUDED).


Study of Longitudinal Distributions in the Fragmentation Regions, Using the Quark - Parton Model in $K^- p$ Interactions at 70-{GeV}/$c$

de Billy, L. ; Briand, H. ; Dumarchez, J. ; et al.
Nucl.Phys.B 191 (1981) 574-590, 1981.
Inspire Record 10816 DOI 10.17182/hepdata.34218

The study of π ± , π 0 , K 0 and Λ production in the fragmentation regions (| x |0.2) of K − p interactions at 70 GeV/ c shows that the x -dependence of each invariant cross section is well described by the power law (1−| x |) n suggested by the dimensional counting rule. Furthermore, pion production is found, both in K − and proton fragmentation regions, to be very similar to their production in ν( ν ) p interactions as expected from quark-parton models. The quark and diquark fragmentation functions D u π , D uu π and D ud π are extracted from our data.

1 data table
Table 1

No description provided.


Cross-section and $p \bar{p}$ Invariant Mass Distribution of the Reaction $\gamma p \to p \bar{p} p$ at 4.7-{GeV} $\le e \gamma \le$ 6.6-{GeV}

Bodenkamp, J. ; Fries, D.C. ; Markou, A. ; et al.
Phys.Lett.B 133 (1983) 275-278, 1983.
Inspire Record 10564 DOI 10.17182/hepdata.30612

Cross section and pp¯ in variant mass distribution of the reaction γp→pp¯p are presented. Further evidence for a narrow pp¯ mass state at 2.023 GeV will be given.

3 data tables
Table 1

Axis error includes +- 0.0/0.0 contribution (?////SYSTEMATIC ERRORS HAVE BEEN FOLDED IN QUADRATURE WITH STATISTICAL ERRORS).

Table 2

Axis error includes +- 0.0/0.0 contribution (?////SYSTEMATIC ERRORS HAVE BEEN FOLDED IN QUADRATURE WITH STATISTICAL ERRORS).

Table 3

Axis error includes +- 0.0/0.0 contribution (?////SYSTEMATIC ERRORS HAVE BEEN FOLDED IN QUADRATURE WITH STATISTICAL ERRORS).


MEASUREMENTS OF LAMBDA0 POLARIZATION PRODUCED BY 40-GeV NEUTRONS ON CARBON NUCLEI IN INCLUSIVE PROCESSES

The Dubna-Berlin-Moscow-Prague-Sofiya-Tbilisi collaboration Aleev, A.N. ; Arefev, V.A. ; Balandin, V.P. ; et al.
JINR-P1-81-165, 1981.
Inspire Record 165431 DOI 10.17182/hepdata.39207

None

1 data table
Table 1

No description provided.


Energy Dependence of Transverse Momentum Invariant Distribution of Pions and Neutral Kaons in $K^- p$ Interactions Between 14.3-{GeV}/$c$ and 70-{GeV}/$c$

Laffaille, J.M. ; Barloutaud, R. ; Louedec, C. ; et al.
Nucl.Phys.B 192 (1981) 18, 1981.
Inspire Record 156048 DOI 10.17182/hepdata.34202

The energy dependence of the transverse momentum invariant distribution of pions and neutral kaons is studied in K − p interactions between 14.3 and 70 GeV/ c . The large P T part of the distributions violates the Feynman scaling and, above P T ≃ 1.5 GeV/ c , appears to be reasonably described by hard scattering models. The variation of the average transverse momentum is also studied as a function of the c.m. reduced longitudinal momentum, and its behaviour is compared to the data obtained via the hadronic shower produced in lepton-hadron interactions.

2 data tables
Table 1

HERE K0 MEANS K0 OR AK0 I.E. K(NEUTRAL).

Table 2

No description provided.


Inclusive $\K^0$(s), $\Lambda$ and Anti-lambda Production in $\pi^+ D$ Interactions at 24-{GeV}/c

Dado, S. ; Goldberg, J. ; Toaff, S. ; et al.
Phys.Rev.D 22 (1980) 2656, 1980.
Inspire Record 8878 DOI 10.17182/hepdata.4164

We have studied inclusive KS0, Λ, and Λ¯ production in π+d interactions at 24 GeV/c. The observed cross sections are 2.5±0.13 mb for KS0, 1.62±0.09 mb for Λ, and 0.12±0.02 mb for Λ¯. Longitudinal- and transverse-momentum distributions of the produced particles are presented. The average charged multiplicities of the system associated with a KS0 or with a Λ are presented and discussed. A nonzero average Λ polarization (-0.10±0.03) is observed. The x distribution of the backward (forward) KS0 and Λ produced in the reaction are in agreement with the x distribution of valence quarks in nucleons in nuclear target (pion beam), as predicted by the quark-recombination model of particle production applied to nuclear targets.

14 data tables
Table 1

Axis error includes +- 0.0/0.0 contribution (?////THE QUOTED IN THE TABLES ERROR INCLUDE ESTIMATES OF UNCERTAINTY IN EACH OF THE CORRECTIONS MADE IN ADDITION TO THE STATISTICAL ERRORCORRECTIONS HAVE BEEN MADE FOR DETECTION, MEASURING, AND FITTING LOSSES AS WELL AS FOR NEUTRAL DECAY MODES OF THE STRANGE PARTICLESNO CORRECTION WAS MADE FOR CONTAMINATION FROM KL'S NOR FOR UNAVOIDABLE INCLUSION OF SIGMA0 EVENTS).

Table 2

Axis error includes +- 0.0/0.0 contribution (?////THE QUOTED IN THE TABLES ERROR INCLUDE ESTIMATES OF UNCERTAINTY IN EACH OF THE CORRECTIONS MADE IN ADDITION TO THE STATISTICAL ERRORCORRECTIONS HAVE BEEN MADE FOR DETECTION, MEASURING, AND FITTING LOSSES AS WELL AS FOR NEUTRAL DECAY MODES OF THE STRANGE PARTICLESNO CORRECTION WAS MADE FOR CONTAMINATION FROM KL'S NOR FOR UNAVOIDABLE INCLUSION OF SIGMA0 EVENTS).

Table 3

Axis error includes +- 0.0/0.0 contribution (?////THE QUOTED IN THE TABLES ERROR INCLUDE ESTIMATES OF UNCERTAINTY IN EACH OF THE CORRECTIONS MADE IN ADDITION TO THE STATISTICAL ERRORCORRECTIONS HAVE BEEN MADE FOR DETECTION, MEASURING, AND FITTING LOSSES AS WELL AS FOR NEUTRAL DECAY MODES OF THE STRANGE PARTICLESNO CORRECTION WAS MADE FOR CONTAMINATION FROM KL'S NOR FOR UNAVOIDABLE INCLUSION OF SIGMA0 EVENTS).

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