Bell, J.
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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.


Polarization in Inclusive $\Lambda$ and $\bar{\Lambda}$ Production at Large $p_T$

Lundberg, B. ; Handler, R. ; Pondrom, L. ; et al.
Phys.Rev.D 40 (1989) 3557-3567, 1989.
Inspire Record 287809 DOI 10.17182/hepdata.23077

A study of the inclusive polarization of Λ hyperons produced by 400-GeV/c protons incident on nuclear targets has been performed at Fermilab. The polarization P of the Λ has been mapped over a large range of xF and pT to good precision for pT up to 3.8 GeV/c. The magnitude of the polarization at fixed xF rises with pT to a plateau at about 1 GeV/c, and the size of the plateau increases monotonically with xF. The Λ¯ were found to be unpolarized for pT<2.4 GeV/c. A target-nucleus dependence for the Λ polarization has been observed.

17 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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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.

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Multiparticle Production by 200-GeV/c Hadrons on Gold, Silver, and Magnesium Targets

Brick, D.H. ; Widgoff, M. ; Beilliere, P. ; et al.
Phys.Rev.D 39 (1989) 2484-2493, 1989.
Inspire Record 282254 DOI 10.17182/hepdata.23227

We have used the Fermilab 30-in. bubble-chamber hybrid spectrometer to study multiparticle production in the interactions of 200-GeV/c protons and π+ and K+ mesons with nuclei of gold, silver, and magnesium. We find that the multiplicities of produced particles and negative particles increase linearly with the number of projectile collisions, with no beam or target dependence. The number of secondary collisions in the nucleus increases significantly less rapidly with the number of projectile collisions than has been reported by a streamer chamber experiment. The properties of secondary collisions suggest that they arise from rescattering of recoil nucleons rather than intranuclear cascade of produced particles. Dispersions of multiplicity distributions at fixed impact parameter are in better agreement with a model of independent sources than with Koba-Nielsen-Olesen scaling.

3 data tables
Table 1

No description provided.

Table 2

PION means all charged secondaries except identified protons.

Table 3

No description provided.


Charm Photoproduction

The Tagged Photon Spectrometer collaboration Anjos, J.C. ; Appel, J.A. ; Bean, A. ; et al.
Phys.Rev.Lett. 62 (1989) 513-516, 1989.
Inspire Record 289318 DOI 10.17182/hepdata.20043

We present results on the photoproduction of 10 000 charmed particles from the 108 recorded triggers of Fermilab experiment E691. The total cross section for the photoproduction of D0 and D+ particles (and antiparticles) for xF>0.2 is measured to be 3.88±0.06±0.40 μb/Be nucleus at 〈Eγ〉=145 GeV. We have also measured the relative production of different charmed particles, their pT2 and xF distributions, and the energy dependence of the total charm cross section. The mean pT2 is 1.16±0.04 GeV2/c2 and the ratio of charm cross sections at 200 and 100 GeV is 1.96±0.24. Results of fits to the xF distribution are also reported.

12 data tables
Table 1

D0/AD0 cross section from K-PI+/K+PI- decay mode.

Table 2

D+/D- cross section from K-2PI+/K+2PI- decay mode.

Table 3

D*+/D*- cross section from D0<K-PI+>PI+ + CC decay mode.

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The Production of $J/_{\psi}$ and Associated Particles in the Collision of 530 GeV/c Protons and Pions with Nuclear Targets

De, K. ; Crittenden, R. ; Dzierba, A. ; et al.
(1989) 467-472, 1989.
Inspire Record 280605 DOI 10.17182/hepdata.22998

None

3 data tables
Table 1

Interacting beam cross-section.

Table 2

No description provided.

Table 3

No description provided.


Lambda0 and anti-Lambda0 Production from Proton - anti-Proton Collisions at s**(1/2) = 1.8-TeV

The E735 collaboration Banerjee, S. ; Beery, P.D. ; Biswas, N.N. ; et al.
Phys.Rev.Lett. 62 (1989) 12, 1989.
Inspire Record 24875 DOI 10.17182/hepdata.20125

The transverse-momentum spectra of lambdas (Λ0, Λ¯0) produced in the central region has been measured in p¯p collisions at s=1.8 TeV at the Fermilab Collider. We find that the average transverse momentum of the lambdas increases more rapidly with center-of-mass energy than that of charged particles, and the ratio of lambdas to charged particles increases as a function of center-of-mass energy.

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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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.


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.