De Lesquen, A.
[2.0, 5.0]
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Electroproduction of $\rho^0$ Mesons

Cohen, I. ; Erickson, R. ; Messing, F. ; et al.
Phys.Rev.D 25 (1982) 634, 1982.
Inspire Record 152921 DOI 10.17182/hepdata.47139

Cross sections for ρ0 electroproduction measured in a streamer-chamber experiment are separated into elastic (ep→epρ0) and inelastic production channels. For the elastic channel, the total cross section and t dependence are presented. For the inelastic channel (1σ)dσdz, (1σ)dσdpT2, and a density matrix element are shown and compared to quark-parton-model predictions. The ratio of ρ0 to direct π0 production is found to be 2.0±0.5±0.3, where the first error is statistical, and the second error is systematic.

8 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Diffraction Dissociation, Resonances and Deck Mechanism in the $K \omega$ Systems of the Reactions $K^+^- p \to$ ($K^+^- \omega$) $p$

The Aachen-Berlin-CERN-London-Vienna & Birmingham-Brussels-CERN-Mons-Serpukhov collaborations Otter, G. ; Rudolph, G. ; Wieczorek, H. ; et al.
Nucl.Phys.B 181 (1981) 1-21, 1981.
Inspire Record 153195 DOI 10.17182/hepdata.34348

A study is presented of the reactions K + p→(K + ω )p at 8.25 and 16 GeV/ c and K − p→(K − ω )p at 10 and 16 GeV/ c and comparison is made with K + results at 10 GeV/ c and K − at 7.3 GeV/ c . The (K + ω) and (K − ω) mass spectra both present a strong enhancement very near threshold, while a second peak at ∼1.7 GeV is evident only with incident K − at the lower energies. The threshold peak has very weak energy dependence and is mostly due to the 1 + S state which is produced conserving s -channel helicity. It is suggested that this is another decay mode of the resonance Q 1 (1290) known to decay mainly into Kϱ. The ratio of the Q 1 coupling constants to the Kω and Kϱ decay channels, R ω = g K ω 2 / g K ϱ 2 is determined to be 0.21±0.04. The enhancement at 1.7 GeV is predominantly, but not exclusively, due to the 2 − state. While the K + and K − induced reactions give basically similar results, small differences are observed that can be qualitatively explained in the framework of the Deck model.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


General Features of the Anti-p $p$ Interaction at 12-{GeV}/c

Johnson, P. ; Mason, P. ; Muirhead, H. ; et al.
Nucl.Phys.B 173 (1980) 77-92, 1980.
Inspire Record 8886 DOI 10.17182/hepdata.34472

Simple inclusive cross sections for p p interactions at 12 GeV/ c are given. The data cover prong cross sections, V 0 production and resonances. Separation has been made into annihilation and non-annihilation modes. Some implications of the data are discussed. It is pointed out that the ratios of cross sections for ϱ 0 π − production are independent of incident antiproton momentum in p p annihilation processes, and that data at the highest available pp energies (ISR) tend to the same value.

1 data table
Table 1

NORMALIZED TO A TOTAL CROSS SECTION OF 51.7 +- 0.8 MB.


Analysis of the Inclusive Reaction $\pi^- p \to K^*$ (890) X0 at 10-{GeV}/c

The Bari-Bonn-CERN-Daresbury-Glasgow-Liverpool-Milan-Vienna collaboration Di Gennaro, V. ; Evangelista, C. ; Ghidini, B. ; et al.
Nucl.Phys.B 173 (1980) 107-126, 1980.
Inspire Record 153000 DOI 10.17182/hepdata.34495

Experimental results on the reaction π − p → K ∗0 (890) X 0 at 10 GeV /c are presented. By using the K ∗0 polarization measurements, a detailed study of the production has been carried out as a function of the missing mass squared and of the four-momentum trasnfer squared to the K ∗0 . We found that: (a) K ∗0 production is dominated by natural parity exchange; (b) K ∗0 helicity-zero production dominates the unnatural parity exchange contribution and (c) the main features of the reaction are in agreement with the predictions of the finite mass sum rules.

4 data tables
Table 1

TO TAL (NATURAL+UNATURAL PARITY EXCHANGE) CROSS-SECTIONS.

Table 2

NATURAL PARITY EXCHANGE CROSS-SECTIONS.

Table 3

UNATURAL PARITY EXCHANGE CROSS-SECTIONS.

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Measurements of the Polarization Parameters in G and $H$ in Positive Pion Photoproduction

Bussey, P.J. ; Rutherglen, J.G. ; Booth, P.S.L. ; et al.
Nucl.Phys.B 169 (1980) 403-414, 1980.
Inspire Record 152385 DOI 10.17182/hepdata.43803

Measurements have been made of the polarisation parameters G and H for the process γ p→ π + n in the photon energy range 600–1875 MeV and pion c.m. angles between 30° and 100°. These data were obtained in a double polarisation experiment, in which the polarised photon beam from the Daresbury electron synchrotron was incident upon a polarised proton target. Theoretical predictions from a current analysis are compared with the data.

7 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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MEASUREMENT AND PARTIAL WAVE ANALYSIS OF THE REACTION K- P ---> K0(S) PI+ PI- N AT 6-GEV/C

Etkin, A. ; Foley, K.J. ; Goldman, J.H. ; et al.
Phys.Rev.D 22 (1980) 42-60, 1980.
Inspire Record 157981 DOI 10.17182/hepdata.24157

We have performed a partial-wave analysis of the reaction K−p→KS0π+π−n at 6 GeV/c. We present the results of the analysis of about 4500 events in the low-t region (|t′|<0.2 GeV2) for the dominant waves in the 1200-to-2000-MeV mass range. We observe the 2+ K*(1430) and clear signals for the 1+ Q2(1400) and the 3− K*(1800). We find a new 1− resonance at about 1500 MeV and have some evidence for another 1− resonance at 1800 MeV. We also present the results of a partial-wave analysis as a function of t in the 1430-MeV mass region.

1 data table
Table 1

TP DEPENDENCE OF PARTIAL WAVES ALSO STUDIED.


CROSS-SECTIONS FOR PI- + P ---> N + (K) PI0 (K = 1 TO 5) AND PI- + P ---> N + ETA0 (ETA0 ---> 2 GAMMA) FOR INCIDENT PION MOMENTA BETWEEN 1.3-GEV/C AND 3.8-GEV/C

Crouch, H.R. ; Hargraves, R. ; Lanou, R.E. ; et al.
Phys.Rev.D 21 (1980) 3023-3058, 1980.
Inspire Record 158169 DOI 10.17182/hepdata.4334

This paper presents the results of a study of the dominant neutral final states from π−p interactions. The data were obtained in an experiment performed at the Brookhaven National Laboratory Alternating Gradient Synchrotron, using a set of steel-plate optical spark chambers surrounding a liquid-hydrogen target. We present differential and total cross sections for the reactions (1) π−p→n+π0 and (2) π−p→n+η0(η0→2γ) and total cross sections for the reactions (3) π−p→n+kπ0 (k=2, 3, 4, and 5) and (4) π−p→all neutrals for eighteen values of beam momentum in the interval 1.3 to 4.0 GeV/c. The angular distributions for (1) and (2) have been analyzed in terms of expansions in Legendre polynomials, the coefficients for which are also given.

41 data tables
Table 1

No description provided.

Table 2

SIG = 4*PI*LEG(L=0).

Table 3

FORWARD DIFFERENTIAL CROSS SECTION CALCULATED FROM LEGENDRE POLYNOMIAL COEFFICIENTS AND ERROR MATRICES.

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OBSERVATION OF THE REACTION K- P ---> B- Y*+ AT 8.25-GeV/c

The BIRMINGHAM-CERN-GLASGOW-MICHIGAN STATE-PARIS collaboration Bloodworth, I.J. ; Carney, J.N. ; Cowan, C.A. ; et al.
Lett.Nuovo Cim. 27 (1980) 555-561, 1980.
Inspire Record 157726 DOI 10.17182/hepdata.37367

None

4 data tables
Table 1

No description provided.

Table 2

DOMINANT NATURAL PARITY EXCHANGE.

Table 3

EVIDENCE FOR FORWARD DIP FOR -TP < 0.1 GEV**2.

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AN AMPLITUDE ANALYSIS OF THE K+ K- SYSTEM PRODUCED IN THE REACTION PI- P ---> K+ K- N AT 10-GEV/C

The BARI-BONN-CERN-GLASGOW-LIVERPOOL-MILAN-VIENNA collaboration Costa, G. ; Donald, R.A. ; Edwards, D.N. ; et al.
Nucl.Phys.B 175 (1980) 402-434, 1980.
Inspire Record 159739 DOI 10.17182/hepdata.34458

We present results on an amplitude analysis of the K + K − system produced in the reaction π − p→K + K − n from threshold up to 2.2 GeV. The branching ratios of f 0 and f' to K K have been determined. In the low mass region of the K K system the observation of an S-wave enhancement at 1.3 GeV and the interference of the f 0 -A 2 -f' mesons are studied. We observe a 3 − structure in the mass region of 1.7 GeV which is consistent with g 0 production. With this interpretation the branching ratio g→ K K has been determined. Evidence for a new structure in the J p = 2 + wave around 1.8 GeV with a width of ∼200 MeV is presented.

2 data tables
Table 1

HELICITY ZERO D-WAVE AMPLITUDE FITTED BY SUM OF BREIT-WIGNER RESONANCES. F 14 GIVES T-DEPENDENCE. ALSO EVIDENCE FOR 1.8 GEV STATE WITH 0.60 +- 0.13 MUB PRODUCTION CROSS SECTION.

Table 2

FROM HELICITY ZERO F-WAVE AMPLITUDE ASSUMING PREDOMINANTLY G(1680)0 PRODUCTION. F 16 GIVES T-DEPENDENCE.


A STUDY OF THE REACTIONS ANTI-K0 P ---> LAMBDA PI+ (BACKWARD) AND ANTI-K0 P ---> SIGMA0 PI+ (BACKWARD) FOR KAON MOMENTA BETWEEN 1 AND 8-GEV/C

Bamberger, A. ; Bruning, H. ; Brundiers, H.J. ; et al.
Nucl.Phys.B 174 (1980) 277-299, 1980.
Inspire Record 159454 DOI 10.17182/hepdata.34465

We present results for the reactions K 0 p →Λπ + and K 0 p →∑ 0 π + , for |u'| <0. 05 ( GeV /c) 2 and kaon momenta between 1 and 8 GeV/ c . The experiment was performed ina neutral beam at the PS with a two arm spark chamber spectrometer. The cross sections show strong dependence on beam energy and momentum transfer u ′. Λ polarization is compatible with zero. We compare energy dependence of the backward cross sections with the baryon exchange model from π N scattering.

8 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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