Allison, W.W.
Pion-Proton Scattering
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PRODUCTION OF PHOTONS ASSOCIATED WITH THE PSI BY 217-GEV/C PI- MESONS

Kirk, T.B.W. ; Raja, R. ; Goodman, M. ; et al.
Phys.Rev.Lett. 42 (1979) 619-622, 1979.
Inspire Record 145303 DOI 10.17182/hepdata.20780

Dimuon production is studied in 217-GeV/c π−-hydrogen and π−-beryllium collisions with a lead-glass array to detect photons associated with the ψ. The ψ−γ mass spectrum shows a 2.6-standard-deviation excess of events above background at ∼3.5 GeV. This excess, if attributed to the decay χ(∼3.5)→ψγ, implies that 0.70±0.28 of the ψ's are produced via radiative decay of one of the χ states.

2 data tables
Table 1

E*D(SIG)/D(XL) is fitted by (1-X)**POWER.

Table 2

No description provided.


$D \bar{D}$ Correlations in 360-{GeV}/$c \pi^- p$ Interactions

The NA27 & LEBC-EHS collaborations Aguilar-Benitez, M. ; Allison, W.W. ; Baland, J.F. ; et al.
Phys.Lett.B 164 (1985) 404-409, 1985.
Inspire Record 216598 DOI 10.17182/hepdata.49642

Charm-charm correlation properties are studied in detail for the first time using a sample of D D pairs produced in 360 GeV/ c π − p interactions. The data are compared with various models of charm production.

1 data table
Table 1

No description provided.


A Search for F Production in 360-{GeV}/$c \pi^- p$ Interactions

The LEBC-EHS collaboration Aguilar-Benitez, M. ; Allison, W.W. ; Baland, J.F. ; et al.
Phys.Lett.B 156 (1985) 444-450, 1985.
Inspire Record 214934 DOI 10.17182/hepdata.30417

We present the results of a search for charm F mesons in 360 GeV/ c π − p interactions. Several methods have been used; all yield no evidence for the F and are interpreted as 90% confidence level cross section upper limits.

2 data tables
Table 1

D/S+- lifetime was assumed tau = 3.2*10**-13 s.

Table 2

D/S+- lifetime was assumed tau = 3.2*10**-13 s.


Charm Hadron Properties in 360-GeV/c $\pi^-$ p-Interactions

The LEBC-EHS collaboration Aguilar-Benitez, M. ; Allison, W.W.M. ; Bailly, J.L. ; et al.
Z.Phys.C 31 (1986) 491-511, 1986.
Inspire Record 214935 DOI 10.17182/hepdata.15883

A study of the properties of charm particles produced in 360 GeV/c π-p interactions is reported. The experiment was performed using the high resolution hydrogen bubble chamber LEBC in association with the European Hybrid Spectrometer at the CERN SPS. Details of the exposure and operation of the spectrometer are given and the methods used to extract the charm data are presented. The essential physics results on the decay properties (lifetime, branching ratios) as well as on the hadroproduction properties (cross sections forD,\(\bar D\),F, Λc,D, correlations between charm particles) are given.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


NEW RESULTS ON NEUTRAL D MESON PROPERTIES IN 360-GeV/c pi- p INTERACTIONS

Aguilar-Benitez, M. ; Allison, W.W. ; Barr, V.M. ; et al.
IFVE-85-21, 1985.
Inspire Record 223942 DOI 10.17182/hepdata.40961

None

1 data table
Table 1

No description provided.


THE REACTIONS P P ---> P P PI+ PI-, K+ P ---> K+ P PI+ PI-, PI+ P ---> PI+ P PI+ PI- AND PI- P ---> PI- P PI+ PI- AT 147-GeV/c

Brick, D.H. ; Rudnicka, H. ; Shapiro, A.M. ; et al.
Z.Phys.C 19 (1983) 1-9, 1983.
Inspire Record 194363 DOI 10.17182/hepdata.16321

We have studied the reactionspp→ppπ+π-,K+p→K+pπ+π−π, π+p→ π+,pπ+π− and π−p →π+π− at 147 GeV/c using the 30-inch Fermilab hybrid system. All four reactions were detected with the same apparatus and analyzed in the same way. The energy dependence of the channel cross section was found to beAp−0.6+B for thepp reaction andAp−1+B for the other three. About 90% of the cross section at 147 GeV/c can be accounted for by either beam or target diffraction. Some of the remaining cross section may come from double Pomeron exchange reactions which we tried to isolate. We have tested the hypothesis of a factorizable Pomeron and our data indicates a violation of this hypothesis. We show that the 3π mass enhancement in the mass region 1.2–1.4 GeV is diffractively produced in the π± beam reactions. Fourprong, four-constraint and six-prong, four-constraint cross sections are reported.

6 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

CROSS SECTIONS FOR DIFFRACTION DISSOCIATION OF BEAM. FEYNMAN X OF OUTGOING PROTON <-0.96.

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Topological, Total and Elastic Cross-sections for $K^+ p$, $\pi^+ p$ and $p p$ Interactions at 147-{GeV}/$c$

Brick, D. ; Rudnicka, H. ; Shapiro, A.M. ; et al.
Phys.Rev.D 25 (1982) 2794, 1982.
Inspire Record 11840 DOI 10.17182/hepdata.4111

The Fermilab hybrid 30-in. bubble-chamber spectrometer was exposed to a tagged 147-GeV/c positive beam containing π+, K+, and p. A sample of 3003 K+p, 19410 pp, and 20745 π+p interactions is used to derive σn, 〈n〉, f2cc, and 〈nc〉D for each beam particle. These values are compared to values obtained at other, mostly lower, beam momenta. The overall dependence of 〈n〉 on Ea, the available center-of-mass energy, for these three reactions as well as π−p and pp interactions has been determined.

13 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Inclusive Strange Resonance Production in $p p$, $\pi^+ p$ and $K^+ p$ Interactions at 147-{GeV}/$c$

Brick, D. ; Rudnicka, H. ; Shapiro, A.M. ; et al.
Phys.Rev.D 25 (1982) 2248-2258, 1982.
Inspire Record 176545 DOI 10.17182/hepdata.23976

We have studied the inclusive production of K*±(890) and Y*±(1385) in pp, π+p, and K+p interactions at 147 GeV/c. The experiment used the Fermilab 30-inch hydrogen bubble chamber with the hybrid spectrometer system. Results are based on a sample of 1916 observed KS and 932 observed A. Inclusive cross sections are given for K*± and Y*± production from the three beams, and comparisons are made with experiments at other energies. Feynman-x and transverse-momentum-squared distributions are also calculated. The results suggest that the K*− is entirely produced in the central region, while the K*+ includes a component from beam fragmentation. Comparisons are made with the additive quark model.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


The Effective Energy Dependence of the Charged Particle's Multiplicity in $P / \pi^+ / K^+$ Interactions on Protons at 147-{GeV}/c

Brick, D. ; Rudnicka, H. ; Shapiro, A.M. ; et al.
Phys.Lett.B 103 (1981) 241-246, 1981.
Inspire Record 170358 DOI 10.17182/hepdata.6707

The energy dependence of the average of the charged multiplicity and its dispersion in π + /K + /p interaction on protons at 147 GeV/ c is found to be the same as in e + e − annihilations if an “effective energy” variable is used instead of the total energy. The effective energy S eff is defined as the invariant mass of all secondaries left after the two leading particles have been removed. Fitting the expression aS eff b to the average charge multiplicity 〈 n ch 〉, we find the power b to be in good agreement with the value of 0.25 predicted by Fermi's statistical model and by Landau's hydrodynamical model.

6 data tables
Table 1

BINS IN WEFF SELECTED SO AS TO YIELD 200 EVENTS IN EACH BIN.

Table 2

200 EVENTS IN EACH BIN IN WEFF.

Table 3

50 EVENTS IN EACH BIN IN WEFF.

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Inclusive and Semiinclusive $\rho^0$ Production in $\pi^+ / \pi^- / K^+ / P P$ Interactions at 147-{GeV}/$c$

Schouten, M. ; De Bock, H. ; Dziembowski, Z. ; et al.
Z.Phys.C 9 (1981) 93-104, 1981.
Inspire Record 170594 DOI 10.17182/hepdata.1419

In an experiment with the 30-inch Hybrid Spectrometer at Fermilab we have obtained the inclusive and semi-inclusive production cross sections of the ϱ0 meson using a conventional background subtraction technique. Production cross sections for the ϱ0 are derived as a function of the Feynman scaling variablex, and the transverse variablespt2 andEt=(pt2+M2)1/2. The longitudinal distributions are compared with the (1−x) dependence of the proton and meson valence quark structure functions, using various forms of recombination and fragmentation models. The transverse distributions are compared with thermodynamic models. We give density matrix elements for the ϱ0 production from pions in the extreme forward region.

6 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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