Meschi, Emilio
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A High Statistics Study of Upsilon Meson Production in $\pi^- W$ Reactions at 286-{GeV}/$c$

The NA10 collaboration Grossmann-Handschin, M. ; Guanziroli, M. ; Le Coultre, P. ; et al.
Phys.Lett.B 179 (1986) 170, 1986.
Inspire Record 230301 DOI 10.17182/hepdata.30229

With a sample of about 2000( γ + γ ′+ γ ″) events observed in π-W interactions at 286GeV/ c , the ratio ( γ ′+ γ ″)/ γ =0.51±0.07, the branching ratio times the inclusive total cross section Bσ =(386±17±85) pb per W nucleus, as well as the differential cross sections in χ F and p T have been measured. These results are compared with previous data obtained with the same apparatus at a lower beam momentum (194 GeV/ c ). Both data sets are compared with a theoretical calculation (“duality model”) which also allows one to extract the shape parameter β g of the gluon distribution in the pion. β g is found to be 2.3 −0.3 +0.4 (stat.) −0.5 +0.1 (syst.).

1 data table
Table 1

No description provided.


Upper Limits for $B \bar{B}$ Production in $\pi^-$ Tungsten Interactions at 194-{GeV}/$c$

The NA10 collaboration Ereditato, A. ; Gorini, E. ; Strolin, Paolo Emilio ; et al.
Phys.Lett.B 157 (1985) 463-468, 1985.
Inspire Record 213161 DOI 10.17182/hepdata.30393

We present a study of events with three muons in the final state, produced in π − -tungsten interactions at 194 GeV/ c . Trimuons can be attributed to B-meson pair production, and this allows us to set (model-dependent) upper limits for the corresponding cross section. Assuming a correlated central production model, we obtain the limit of 1.5 nb per nucleon at the 95% confidence level.

1 data table
Table 1

No description provided.


A-dependence of Muon Pair Production in $\pi^-$ Nucleus Interactions at 280-{GeV}/$c$

Falciano, S. ; Freudenreich, K. ; Juillot, P. ; et al.
Phys.Lett.B 104 (1981) 416-420, 1981.
Inspire Record 166161 DOI 10.17182/hepdata.31061

We have measured the relative cross sections for muon pair production by 280 GeV/ c negative pions on three different targets: carbon, copper, and tungsten. The value of α obtained from the parametrization σ = constant × A α is 0.94 ± 0.02 ± 0.02, whereas the parametrization σ≈σ 0 ( Z A ) A α′ , where σ 0 ( Z A ) is given by the Drell-Yan model, leads to α ′ = 0.97 ±0.02±0.02. This last result is in agreement with the quark additivity rule which is inherent in the Drell-Yan model, no dependence is observed on the transverse momentum of the muon pair.

2 data tables
Table 1

PARAMETRISATION OF CROSS-SECTION IS SIG=CONST.*A**POWER.

Table 2

PARAMETRISATION OF CROSS-SECTION IS SIG=SIG0(Z/A)*A**POWER WHERE SIG0(Z/A) IS GIVEN BY DRELL-YAN MODEL.


Production of High Transverse Momentum Low Mass Electron - Positron Pairs in High-energy $p p$ Collisions

Chilingarov, A. ; Clark, A.G. ; Darriulat, P. ; et al.
Nucl.Phys.B 151 (1979) 29-45, 1979.
Inspire Record 133024 DOI 10.17182/hepdata.34778

The production of electron-positron pairs of masses below 1200 MeV/ c 2 and of transverse momentum above 1.8 GeV/ c has been studied in pp collisions at √ s = 53 and 63 GeV. The cross section for ϱ, ω, and φ production are presented. The continuum below 600 MeV/ c 2 is consistent with origination from Dalitz decays of η and ω mesons and from semileptonic decay of D and D mesons.

1 data table
Table 1

No description provided.


Large Transverse Momentum $\pi^0$ Production in Proton Proton, Deuteron Proton, and Deuteron-deuteron Collisions at the {CERN} {ISR}

Clark, A.G. ; Darriulat, P. ; Eggert, K. ; et al.
Nucl.Phys.B 142 (1978) 189-204, 1978.
Inspire Record 130468 DOI 10.17182/hepdata.35022

Measurements are presented of the inclusive π 0 production cross section, in the transverse momentum range 2.3 ⪅ p T ⪅4.5 GeV/c, for dd and dp interactions at total c.m. energies of √ s = 52.7 GeV and √ s = 63.2 GeV and for pp interactions at √ s = 52.7 GeV. The produced π 0 's are detected by identifying both protons from the decay π 0 → γγ . As in pp interactions, the data can be adequately described by a p T −n ƒ(x T ) dependence with n ≌ 8 . The data are approximately consistent with the expectations of free nucleon scattering. No significant differenceare observed in either the charged or the neutral particle distributions associated with π 0 , for dd, dp and pp interactions.

5 data tables
Table 1

GLOBAL NORMALIZATION UNCERTAINTY = 12 PCT. RELATIVE NORMALIZATION UNCERTAINTY = 5 PCT.

Table 2

GLOBAL NORMALIZATION UNCERTAINTY = 10 PCT. RELATIVE NORMALIZATION UNCERTAINTY = 6 PCT.

Table 3

GLOBAL NORMALIZATION UNCERTAINTY = 15 PCT. RELATIVE NORMALIZATION UNCERTAINTY = 7 PCT.

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Inclusive $\pi^0$ Production From High-energy $P P$ Collisions at Very Large Transverse Momenta

Clark, A.G. ; Darriulat, P. ; Dittmann, P. ; et al.
Phys.Lett.B 74 (1978) 267-272, 1978.
Inspire Record 6427 DOI 10.17182/hepdata.27460

We report on measurements of inclusive π 0 production at c.m. energies of 53 and 63 GeV, θ ≅90°, from p-p collisions at the CERN ISR. In the range 0.2< x t <0.45 the data can be described by a form: Ed 3 σ d p 3 ∝p − (6.6±0.8) t (1−x t ) (9.6±1.0) .

2 data tables
Table 1

No description provided.

Table 2

No description provided.


First Results on Diffraction Dissociation of Neutrons at the ISR

Mantovani, G.C. ; Cavalli-Sforza, M. ; Conta, C. ; et al.
Phys.Lett.B 64 (1976) 471-474, 1976.
Inspire Record 110024 DOI 10.17182/hepdata.27617

Neutron diffraction dissociation has been measured at the ISR in proton-neutron interactions at 37 GeV c.m. energy. The data were taken with the Split Field Magnet detector, during a short deuteron storage test run with colliding p-d beams. Differential mass and momentum transfer distributions are reported; the value of the total cross-section shows a weak s -dependence when compared to lower energy data.

2 data tables
Table 1

ERROR IS MOSTLY SYSTEMATIC.

Table 2

No description provided.


Production of Nucleon Resonances by Single Diffraction Dissociation at the CERN ISR

Webb, R. ; Trilling, G. ; Telegdi, V. ; et al.
Phys.Lett.B 55 (1975) 331-335, 1975.
Inspire Record 91189 DOI 10.17182/hepdata.27915

The single diffraction dissociation process pp → (p π + π − )p has been studied at the CERN ISR at √ s = 45 GeV and 0.1 < − t < 0.6 GeV 2 . The reaction is dominated by nucleon resonance production: pp → pN (1520) and pp → pN(1688) with cross-sections (0.25 ± 0.08) mb and (0.56 ± 0.19) mb respectively.

2 data tables
Table 1

DIFFERENTIAL CROSS SECTIONS FOR THREE RANGES OF <P PI+ PI-> MASS.

Table 2

FROM BREIT-WIGNER PLUS BACKGROUND FITS. CORRECTIONS FOR OTHER DECAY MODES USE THE PDG 1974 TABLES FOR N(1520) AND N(1688).


Small angle proton proton elastic scattering at very high-energies (460-GeV**2 < s < 2900-GeV**2)

Barbiellini, G. ; Bozzo, M. ; Darriulat, P. ; et al.
Phys.Lett.B 39 (1972) 663-667, 1972.
Inspire Record 73452 DOI 10.17182/hepdata.28304

We have investigated the above processes at the CERN Intersecting Storage Rings (ISR). Results show a marked change of the slope parameter b ( t , s ) = (d/d t ) ln (d σ /d t ) around − t ≈ 0.10 GeV 2 . The s − and t − dependence of b ( t , s ) have been observed over the interval 460 GeV 2 < s < 2900 GeV 2 and 0.02 GeV 2 < t < 0.40 GeV 2 .

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Further results on small angle elastic proton proton scattering at very high energies

Holder, M. ; Radermacher, E. ; Staude, A. ; et al.
Phys.Lett.B 36 (1971) 400-402, 1971.
Inspire Record 69148 DOI 10.17182/hepdata.28407

This work extends our previous investigations at the CERN Intersecting Storage Rings, with improved statistics at three different energies, wider angular range and a better control over systematic errors. Values for the (diffraction) shape parameter b are given.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.