Staude, A.
SLOPE
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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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Observation and Quantum Numbers Determination of the E(1420) Meson in pi- p Interactions at 3.95-GeV/c

The CERN-College de France-Madrid-Stockholm collaboration Dionisi, C. ; Gavillet, P. ; Armenteros, R. ; et al.
Nucl.Phys.B 169 (1980) 1-19, 1980.
Inspire Record 152746 DOI 10.17182/hepdata.34515

In a high statistics (90 events/μb) bubble chamber experiment, the reactions π − p→K s 0 K ± π ∓ n have been studied at 3.95 GeV/ c . A significant enhancement is observed in the ( K K π) system which we attribute to the production of the E(1420) meson. For its mass, M , and width, Λ, we find M =1426±6 MeV and Γ =40±15 MeV. The E(1420) quantum numbers are determined to be I G J P =0 + 1 + with a branching ratio E → K ∗ K + c.c E →[δπ+( K ∗ K + c.c. )]=0.86±0.12 , where δ→ K K . The cross section for the reaction π − p→En, with E→K 0 K ± π ± , is 8.2±1.0 μ b. Forward and backward productions are observed in the approximate ratio 2:1. The SU(3) assignment of the E(1420) meson is discussed.

3 data tables
Table 1

BACKGROUND SUBTRACTED.

Table 2

No description provided.

Table 3

No description provided.


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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Measurement of $\omega$ Meson Photoproduction on Protons From 46 GeV to 180 GeV

Egloff, R.M. ; Davis, P.J. ; Luste, G.J. ; et al.
Phys.Rev.Lett. 43 (1979) 1545, 1979.
Inspire Record 142364 DOI 10.17182/hepdata.3122

Elastic ω-meson photoproduction on protons has been measured from 46 to 180 GeV. The cross section is approximately constant with photon energy and averages 1.10 ± 0.08 μb. The t dependence of the differential cross section is consistent with A exp(bt), where b=8.4±0.7 GeV−2. The photon-omega coupling constant, obtained from a normalization of hadron elastic-scattering cross sections to the photoproduction data of this experiment (with use of vector-meson dominance and an additive quark model), is γω24π=5.4±0.4.

4 data tables
Table 1

THE QUOTED STATISTICAL ERRORS INCLUDE THE UNCERTAINTY IN THE CORRECTION FOR INELASTIC EVENTS. AVERAGE CROSS SECTION IS 1.10 +- 0.08 MUB.

Table 2

EXPONENTIAL FIT TO DIFFERENTIAL CROSS SECTION.

Table 3

No description provided.

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Experimental Proof of the Existence of the A1 Meson

The ACCMOR collaboration Daum, C. ; Hertzberger, L. ; Hoogland, W. ; et al.
Phys.Lett.B 89 (1980) 281-284, 1980.
Inspire Record 143044 DOI 10.17182/hepdata.27272

In partial wave analyses of the ( π − π − π + ) system, substantial shape changes of the 1 + S ( ϱπ ) intensity as a function of t , and relative phase changes of ≈ 90°, provide compelling evidence for a resonant A 1 of mass ≈ 1280 MeV and width ≈ 300 MeV.

1 data table
Table 1

No description provided.


3 $\pi$ Resonances in 2- Partial Waves

The ACCMOR collaboration Daum, C. ; Hertzberger, L. ; Hoogland, W. ; et al.
Phys.Lett.B 89 (1980) 285-289, 1980.
Inspire Record 143045 DOI 10.17182/hepdata.27275

The J PC = 2 −+ partial wave intensities and their large phase changes prove the resonant nature of the A 3 meson (mass ≈ 1670 MeV, width ≈ 210 MeV). The decay modes are f 0 π , ϱ 0 π , and ϵ 0 π . Evidence is found for a further 2 − enhancement.

1 data table
Table 1

No description provided.


A Study of the $\Delta \pi \pi$ System in the Reaction $\pi^- p \to \pi^- p \pi^+ \pi^- \pi^0$ at 4.5-{GeV}/$c$

Sugahara, R. ; Suzuki, A. ; Fukawa, M. ; et al.
Nuovo Cim.A 52 (1979) 373, 1979.
Inspire Record 142331 DOI 10.17182/hepdata.37520

Two (Δ(1238)ππ) enhancements at 1.93 and 2.12 GeV have been observed in an analysis of the invariant-mass spectra of Δ++(1238)π-π0 and Δ++(1238)π-π- from π-p→π-pπ+π-π0 events in 4.5 GeV/c π-p interactions. An enhancement at 2.2 GeV is also seen with a dominant branching to the Δ(1238)ρ system. The 1.93 and 2.12 enhancements seem to be produced mainly through a ρ-meson exchange process. The 2.2 GeV enhancement seems to be produced diffractively and is considered to correspond to theG17(2190) state.

2 data tables
Table 1

No description provided.

Table 2

EXPONENTIAL FITS TO T-DISTRIBUTIONS.


STUDY OF THE UPSILON (9.46) MESON IN ELECTRON - POSITRON ANNIHILATIONS

Darden, C.W. ; Hasemann, H. ; Krolzig, A. ; et al.
Phys.Lett.B 80 (1979) 419-422, 1979.
Inspire Record 145168 DOI 10.17182/hepdata.27358

New data for the reaction e + e − →ϒ(9.46) have been obtained using the DASP detector at the DORIS storage ring. The electronic width Γ ee is (1.5±0.4) keV. The branching ratio for the decay into muon pairs is (2.5 ± 2.1)%. Energy spectra for inclusive production of hadrons are given.

2 data tables
Table 1

VISIBLE HADRONIC TOTAL CROSS SECTION.

Table 2

INVARIANT INCLUSIVE PRODUCTION CROSS SECTION E*D3(SIG)/DP**3 BOTH ON AND OFF THE UPSILON(9.46) RESONANCE. NO SIGNIFICANT DIFFERENCE IN EXPONENTIAL SLOPE AS A FUNCTION OF PARTICLE ENERGY E(P=3).


BACKWARD omega0 AND eta0 PRODUCTION IN pi p INTERACTIONS AT 9-GeV/c AND 12-GeV/c

Benkheiri, P. ; Eisenstein, Bob I. ; Fleury, P. ; et al.
Nucl.Phys.B 150 (1979) 268-286, 1979.
Inspire Record 132166 DOI 10.17182/hepdata.34809

We have studied the backward production of ω 0 mesons in the u -channel I u = 1 2 exchange reaction π − p → N 0 (1680) ω 0 at 9 GeV/ c and 12 GeV/ c incident momenta. The data come from an experiment performed at the CERN Omega Spectrometer using a fast proton trigger device. The backward production of the η 0 meson has also been observed and the coupling constant ratio g η NN / g π NN has been estimated.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

JACKSON FRAME (U-CHANNEL HELICITY SYSTEM).


Backward Production of the $B$ Meson in $K^- p$ Interactions at 4.2-{GeV}/$c$

The Amsterdam-CERN-Nijmegen-Oxford collaboration Gavillet, P. ; Dionisi, C. ; Gurtu, A. ; et al.
Phys.Lett.B 78 (1978) 158-161, 1978.
Inspire Record 131673 DOI 10.17182/hepdata.27430

The backward production of the B(1235) meson is studied in the reaction K − p → Σ − π + ω . This reaction is observed in the final state Σ − π + π + π − π 0 . A π + ω mass enhancement is visible in the region of the B meson for events with small | u |K − → Σ − ) squared four-momentum transfer. The properties of the enhancement agree with those of the B meson. The cross section for K − p → Σ − B + at 4.15 GeV c incident K − momentum is (3.2 ± 0.5) μb . The backward production of the B meson is compared with similar baryon exchange productions of the A 1 and C(Q 1 ) axial vector mesons observed in the same experiment.

2 data tables
Table 1

No description provided.

Table 2

No description provided.