Balestra, F.
hep-ex
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Measurement of Differential Cross-Section and Polarization in the Backward Peak of the Reactions pi- p --> Lambda K0 and pi- p --> Lambda K* (890) at 8-GeV/c

Brundiers, H. ; Hartung, R. ; Runge, K. ; et al.
Nucl.Phys.B 119 (1977) 349-361, 1977.
Inspire Record 123952 DOI 10.17182/hepdata.35527

Differential cross sections and polarizations have been measured for the backward peaks in the reactions π − p →Λ K 0 and π − p →Λ K ∗ (890) at 8 GeV/c. The experiment was performed with a liquid hydrogen target at the ω spectrometer. The cross sections for u′>−2 ( GeV /c) 2 are 0.27 ± 0.03 μ b for π − p →Λ+ K 0 and 0.55±0.07 μ b for π − p →Λ K ∗0 . Large positive Λ polarization was observed in both reactions for u ′>−0.5 (GeV/ c ) 2 . The dominant production mechanism was found to be unnatural baryon exchange.

3 data tables
Table 1

Axis error includes +- 0.0/0.0 contribution (?////).

Table 2

Axis error includes +- 0.0/0.0 contribution (?////).

Table 3

No description provided.


Study of the Reaction d (p, pi+) t at t(p) = 410-MeV, 605-MeV and 809-MeV

Aslanides, E. ; Bertini, R. ; Bing, O. ; et al.
Phys.Rev.Lett. 39 (1977) 1654-1656, 1977.
Inspire Record 126515 DOI 10.17182/hepdata.20981

Pion production on a CD2 target has been measured using the high-resolution magnetic spectrometer SPES I. Differential cross sections for the reaction D(p, π+)T have been determed at Tp=410, 605, and 809 MeV. The present data, together with previous results establish a complete angular distribution of the reaction D(p, π+)T at ∼ 600 MeV and the energy dependence of the differential cross section for this reaction at several constant momentum transfers.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Inelastic Photoproduction of omega and rho+- Mesons

Nelson, C.A., Jr. ; May, E.N. ; Abramson, J. ; et al.
Phys.Rev.D 17 (1978) 647, 1978.
Inspire Record 4373 DOI 10.17182/hepdata.24401

We report measurements of inelastic photoproduction of ω and ρ± mesons from hydrogen and deuterium at incident photon energies in the range 7.5-10.5 GeV. For ωΔ and ρ−Δ++ production, differential cross sections dσdt′ and spin density matrices are presented. For higher missing masses the cross sections dσdMX2 and invariant structure functions F(x) are also given. The data are compared to a one-pion-exchange model. We conclude that pion exchange is dominant for inelastic ω photoproduction, but unimportant for ρ±.

4 data tables
Table 1

CROSS SECTION PER NUCLEON FOR COMBINED HYDROGEN AND DEUTERIUM DATA ALLOWING FOR A GLAUBER CORRECTION FACTOR OF 0.88 FOR THE DEUTERIUM CROSS SECTIONS.

Table 2

HYDROGEN AND DEUTERIUM DATA COMBINED BY AVERAGING.

Table 3

OBTAINED BY EXTRAPOLATING A FIT TO D(SIG)/DT OVER -T = 0 TO 0.52 GEV**2.

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Inclusive Production of Nonstrange Mesons in anti-p p Annihilations

The Bombay-CERN-College de France-Madrid collaboration Hamatsu, R. ; Ganguli, S.N. ; Malhotra, P.K. ; et al.
Nucl.Phys.B 123 (1977) 189, 1977.
Inspire Record 111926 DOI 10.17182/hepdata.35452

A study of the inclusive production of π − , η , ϱ 0 , ω ad f mesons in p p annihilation at 0.7 GeV/ c is presented. Topological and channel cross sections are determined. Longitudinal and transversal momentum distributions of non-strange mesons are studied. It is deduced that nearly 48% of all negative pions arise from the decay of η , ϱ 0 , ω and f mesons.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


The Reactions K- p --> pi-+ Sigma+- at 4.2-GeV/c

The Amsterdam-CERN-Nijmegen-Oxford collaboration Massaro, G.G.G. ; Barlag, S. ; de Groot, A.J. ; et al.
Phys.Lett.B 66 (1977) 385-389, 1977.
Inspire Record 110532 DOI 10.17182/hepdata.27595

We present differential cross sections and the Σ + polarization for the reactions K − p → π ∓ Σ ± using data from a high statistics bubble chamber experiment at 4.2 GeV/ c incident momentum. The statistical level allows a detailed analysis of these reactions over the whole t range. Several significant structures are observed. Comparisons are made with SU(3)-related reactions; for backward production of π − Σ + such a comparison shows good evidence for Δ exchange. The exotic forward peak in K − p → π + Σ − is definitely confirmed.

7 data tables
Table 1

Axis error includes +- 5/5 contribution.

Table 2

Axis error includes +- 5/5 contribution.

Table 3

Axis error includes +- 5/5 contribution.

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Study of Sigma+- (1385) Inclusive Production in K- p Interactions at 4.2-GeV/c

The Amsterdam-CERN-Nijmegen-Oxford collaboration Barreiro, F. ; Berge, J.P. ; Ganguli, S.N. ; et al.
Nucl.Phys.B 126 (1977) 319-339, 1977.
Inspire Record 111752 DOI 10.17182/hepdata.35325

Properties of Σ ± (1385) inclusively produced in 4.2 GeV/ c K − p interactions are studied. Inclusive cross sections are presented together with differential cross sections as functions of x and p t 2 for both Σ + (1385) and Σ − (1385). The complete density matrix for Σ + (1385) production at small momentum transfer is studied as a function of t and of recoil mass MM 2 . Substantial agreement with the predictions of the additive quark model is found. The Σ + (1385) production in the target fragmentation region is studied in the framework of the triple-Regge model.

3 data tables
Table 1

Axis error includes +- 5/5 contribution (ERROR OF NORMALIZATION).

Table 2

Axis error includes +- 5/5 contribution (ERROR OF NORMALIZATION).

Table 3

Axis error includes +- 5/5 contribution (ERROR OF NORMALIZATION).


Production and Decay Properties of f-prime (1514) in K- p Interactions at 4.2-GeV/c

The Amsterdam-CERN-Nijmegen-Oxford collaboration Barreiro, F. ; Diaz, J. ; Gay, J.B. ; et al.
Nucl.Phys.B 121 (1977) 237-250, 1977.
Inspire Record 111490 DOI 10.17182/hepdata.35514

Results are presented for the hypercharge exchange reaction K − p→ f ′(1514) Λ at a beam momentum of 4.15 GeV/ c . Total and differential cross sections have been determined. The Λ polarization and the tensor meson density matrix elements are given as a function of t ′.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

ALL EVENTS WITH 1.46<M(KS KS)<1.60GEV.


Observation of Neutron Neutron Interactions with Double Diffraction Dissociation at the ISR

Mantovani, G.C. ; Cavalli-Sforza, M. ; Conta, C. ; et al.
Phys.Lett.B 65 (1976) 401-404, 1976.
Inspire Record 110581 DOI 10.17182/hepdata.27598

Neutron-neutron interactions have been observed at the CERN ISR with deutron colliding beams. The double - diffraction dissociation process →(p π p − )( pπ − ) has been measured with the Split Field Magnet at √ s = 26 GeV detecting all final state particles, including the two spectator protons. Mass and t distributions are presented and compared with corresponding spectra observed in single neutron diffraction in the same energy range with supporting evidence for factorization. The cross-section of the process is 11.5±2.8 μ b and can be directly related to the corresponding value for double diffraction dissociation of protons in the same energy range.

2 data tables
Table 1

ERROR IS MOSTLY SYSTEMATIC. DEUTERON CORRECTIONS APPLIED.

Table 2

No description provided.


Energy and Momentum Distributions of Muoproduced Hadrons

del Papa, C. ; Dorfan, David E. ; Flatte, Stanley M. ; et al.
Phys.Rev.D 15 (1977) 2425, 1977.
Inspire Record 109678 DOI 10.17182/hepdata.24649

We present inclusive distributions for final-state hadrons produced in inelastic muon-proton scattering. Over the total energy range 2

7 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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The Reactions K- p --> pi-+ Sigma+- (1385) at 4.2-GeV/c

The Amsterdam-CERN-Nijmegen-Oxford collaboration Holmgren, S.O. ; Aguilar-Benitez, M. ; Barreiro, F. ; et al.
Nucl.Phys.B 119 (1977) 261-291, 1977.
Inspire Record 110408 DOI 10.17182/hepdata.35566

The reactions K − p→ π − Σ + (1385) and K − p→ π + Σ − (1385) are studied at 4.2 GeV c incident momentum using data from a high statistics bubble chamber experiment corresponding to ∼80 events/μb. The total and differential cross sections are presented. Amplitude analyses are performed and the complete Σ ± (1385) helicity spin density matrices are extracted. The results are compared with the predictions of the additive quark model and exchange degeneracy. A substantial cross section is observed for the reaction K − p→ π + Σ − (1385) in the forward direction, which implies exotic meson quantum numbers in the t -channel. One possible interpretation of this process provides an explanation for the small but significant violations of the additive quark model predictions observed in the reaction K − p→ π − Σ + (1385) at low four-momentum transfer. In the backward direction unnatural parity exchange is shown to give a larger contribution to K − p→ Σ − (1385) π + than natural parity exchange.

11 data tables
Table 1

Axis error includes +- 5/5 contribution.

Table 2

Axis error includes +- 5/5 contribution.

Table 3

Axis error includes +- 5/5 contribution.

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