Aschman, D.
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INCLUSIVE CHARGED D* PRODUCTION IN 205-GEV/C PI- BE INTERACTIONS

Mooney, P. ; Sarmiento, M. ; Bishop, J.M. ; et al.
Phys.Rev.D 39 (1989) 2494-2498, 1989.
Inspire Record 282266 DOI 10.17182/hepdata.23225

The inclusive cross section for charged-D* production by 205-GeV/c π− mesons incident on a beryllium target was measured with a two-arm spectrometer triggered by prompt muons. Using the mass-difference technique often employed in D* studies, a signal of 31±11 charged D*’s was isolated; it includes contributions from both the D*+ and D*− charged modes in correlation with triggering muons of the proper charge. This corresponds to an inclusive charged-D* production cross section of 220±77−57+77 μb per Be nucleus or 24±9−6+9 μb per nucleon when the cross section is scaled linearly with atomic mass number. The first error is statistical and the second is systematic.

1 data table
Table 1

No description provided.


High-energy Photoproduction of $\pi^+ \pi^- \pi^0$, $K^+ K^-$, and $P \bar{P}$ States

Busenitz, J. ; Olszewski, C. ; Callahan, P. ; et al.
Phys.Rev.D 40 (1989) 1-21, 1989.
Inspire Record 285137 DOI 10.17182/hepdata.23148

We report measurements from elastic photoproduction of ω's on hydrogen for photon energies between 60 and 225 GeV, elastic φ photoproduction on hydrogen between 35 and 165 GeV and on deuterium between 45 and 85 GeV, elastic photoproduction on deuterium of an enhancement at 1.72 GeV/c2 decaying into K+K−, and elastic and inelastic photoproduction on deuterium of pp¯ pairs.

7 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

More…

Experimental Evidence for the Nonabelian Nature of {QCD}

The AMY collaboration Park, I.H. ; Schnetzer, S. ; Green, J. ; et al.
Phys.Rev.Lett. 62 (1989) 1713, 1989.
Inspire Record 276619 DOI 10.17182/hepdata.20045

We present evidence for the non-Abelian nature of QCD from a study of multijet events produced in e+e− annihilations from √s =50 to 57 GeV in the AMY detector at the KEK storage ring TRISTAN. A comparison of the three-jet event fraction at TRISTAN to the fraction of the DESY storage ring PETRA shows that the QCD coupling strength αs decreases with increasing Q2. In addition, measurements of the angular distributions of four-jet events show evidence for the triple-gluon vertex.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


MEASUREMENTS OF THE e+ e- TOTAL HADRONIC CROSS-SECTION AND A DETERMINATION OF M(Z) AND LAMBDA (MS)

The AMY collaboration Mori, T. ; Nozaki, T. ; Blanis, D. ; et al.
Phys.Lett.B 218 (1989) 499-507, 1989.
Inspire Record 276653 DOI 10.17182/hepdata.29847

The total cross section for e + e − annihilation into hadrons has been measured for CM energies ranging from 50 to 57 GeV. We fit the predictions of the standard model to these measurements and those at lower energies. The mass of the Z 0 boson, M Z , and the QCD scale parameter, Λ MS , are derived from the fit. The results are M Z =88.6 −1.8 +2.0 GeV/ c 2 , and Λ MS =0.15 −0.11 +0.16 GeV .

1 data table
Table 1

No description provided.


Anti-proton - Helium Annihilation Around 44-{MeV}/$c$

Balestra, F. ; Bossolasco, S. ; Bussa, M.P. ; et al.
Phys.Lett.B 230 (1989) 36-40, 1989.
Inspire Record 276657 DOI 10.17182/hepdata.49625

The p¯4He annihilation cross section averaged over the interval 40–50 MeV/ c has been measured using a streamer chamber in a magnetic field. The measured value is 1342±250 mb. It agrees with a behaviour like 1/ p of the annihilation cross section. Our result has been obtained at the lowest momentum achieved till now in measurements of antiproton annihilation in flight.

1 data table
Table 1

No description provided.


Production Cross-section and Topological Decay Branching Fractions of the $\tau$ Lepton

The HRS collaboration Abachi, S. ; Derrick, M. ; Kooijman, P. ; et al.
Phys.Rev.D 40 (1989) 902, 1989.
Inspire Record 267739 DOI 10.17182/hepdata.23018

We report new measurements of the production cross section for the reaction e+e−→τ+τ− at s=29 GeV, as well as the topological decay branching fractions of the τ lepton. The data were taken with the High Resolution Spectrometer at the SLAC e+e− colliding-beam facility PEP. The measured cross section yields Rττ=1.044±0.014±0.030 [where the first (second) error is statistical (systematic)], consistent with QED and corresponding to QED cutoff parameters of Λ+>129 GeV and Λ−>284 GeV at the 95% C.L. The fractions of τ decays into one and three charged particles are B1=0.864±0.003±0.003 and B3=0.135±0.003±0.003.

1 data table
Table 1

No description provided.


Limiting Fragmentation in Oxygen Induced Emulsion Interactions at 14.6-a/{GeV}, 60-a/{GeV} and 200-a/{GeV}

The EMU01 collaboration Adamovich, M.I. ; Aggarwal, M.M. ; Arora, R. ; et al.
Phys.Rev.Lett. 62 (1989) 2801, 1989.
Inspire Record 268021 DOI 10.17182/hepdata.20041

Pseudorapidity distributions of relativistic singly charged particles in oxygen-induced emulsion interactions at 14.6, 60, and 200 GeV/nucleon are studied. Limiting fragmentation behavior is observed in both the target and projectile fragmentation regions for a central as well as for a minimum-bias sample. Comparisons with the fritiof model reveal that the picture of fragmenting strings successfully describes the observed data.

2 data tables
Table 1

NUCLEUS IS AVERAGE NUCLEUS OF EMULSION.

Table 2

NUCLEUS IS AVERAGE NUCLEUS OF EMULSION.


THE pi, K, PROTON ELECTROMAGNETIC FORM-FACTORS AND NEW RELATED DM2 RESULTS

The DM2 collaboration Castro, A. ; Bisello, D. ; Busetto, G. ; et al.
LAL-88-58, 1988.
Inspire Record 267117 DOI 10.17182/hepdata.38181

None

1 data table
Table 1

No description provided.


rivet Analysis
Observation of the D*0 (2459) in e+ e- Annihilation

The ARGUS collaboration Albrecht, H. ; Bockmann, P. ; Glaser, R. ; et al.
Phys.Lett.B 221 (1989) 422-426, 1989.
Inspire Record 268577 DOI 10.17182/hepdata.29827

Using the ARGUS detector at the DORIS II storage ring at DESY, we have observed a charmed meson of mass (2455±3±5) MeV/c2, decaying to D + π − . The natural width of this state is determined to be (15 +13+5 −10−10 ) MeV c 2 . The fragmentation function is hard, as expected for a leading charmed particle from nonresonant e + e − annihilation. Analysis of the decay angular distribution supports the hypothesis that the observed state is an L =1 excited charmed meson with spin-parity 2 + .

2 data tables
Table 1

Corrected to zero momentum using fragmentation function of Peterson et al., PR D29 (83) 105.

Table 2

Data read from graph.


rivet Analysis
Measurement of the Reaction $\gamma \gamma \to \rho^+ \rho^-$ With the Cello Detector

The CELLO collaboration Behrend, H.J. ; Criegee, L. ; Dainton, J.B. ; et al.
Phys.Lett.B 218 (1989) 493-498, 1989.
Inspire Record 267081 DOI 10.17182/hepdata.29842

Results on the reaction γγ → π + π − π 0 π 0 are presented. There is clear evidence for correlated ϱ + ϱ − production. The cross section is much lower than for γγ → ϱ 0 ϱ 0 .

2 data tables
Table 1

Results using 3 parameter fit (rho+ rho-, rho+- pi+- pi0, and non-resonant 4pi) to data.

Table 2

Results using 2 parameter fit (rho+ rho-, and non-resonant 4pi) to data.