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Production of $K \bar{K}$ Pairs in Photon-photon Collisions and the Excitation of the Tensor Meson F-prime (1515)

The TASSO collaboration Althoff, M. ; Brandelik, R. ; Braunschweig, W. ; et al.

Phys.Lett.B 121 (1983) 216-222, 1983.

Inspire Record 181468 DOI 10.17182/hepdata.30814

We have observed exclusive production of K + K − and K S O K S O pairs and the excitation of the f′(1515) tensor meson in photon-photon collisions. Assuming the f′ to be production in a helicity 2 state, we determine Λ( f ′ → γγ) B( f ′ → K K ) = 0.11 ± 0.02 ± 0.04 keV . The non-strange quark of the f′ is found to be less than 3% (95% CL). For the θ(1640) we derive an upper limit for the product Λ(θ rarr; γγ K K ) < 0.03 keV (95% CL ) .

2 data tables

Table 1

Data read from graph.. Errors are the square roots of the number of events.

Table 2

Data read from graph.. Errors are the square roots of the number of events.

Characteristics of the Secondary Neutrons in $\pi^- p$, $\pi^- n$ and $\pi^- ^{12}$C Interactions at $P=40$-{GeV}/$c$

Grishin, V.G. ; Korbel, Z. ; Muminov, M.M. ; et al.

Sov.J.Nucl.Phys. 37 (1983) 382, 1983.

Inspire Record 180240 DOI 10.17182/hepdata.9944

None

5 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

FOR P< 1. GEV DATA FOR PROTONS WITH P < .7 WERE USED.

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THE STUDY OF DIFFRACTIVE DISSOCIATION IN THE REACTION anti-p p ---> anti-p p pi+ pi- AT 22.4-GeV/c

The Dubna-Alma Ata-Helsinki-Prague collaboration Batyunya, B.V. ; Boguslavsky, I.V. ; Dashian, N.B. ; et al.

JINR-E1-82-415, 1982.

Inspire Record 179201 DOI 10.17182/hepdata.9875

None

5 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Measurement of $e^+ e^- \to \mu^+ \mu^-$ Charge Asymmetry

Adeva, B. ; Barber, D.P. ; Becker, U. ; et al.

Phys.Rev.Lett. 48 (1982) 1701, 1982.

Inspire Record 177308 DOI 10.17182/hepdata.3116

The measurement of the nonelectromagnetic forward-backward charge asymmetry in the reaction e+e−→μ+μ− at s∼34.6 GeV and in the angular region 0<|cosθ|<0.8 is reported. With a systematic error less than 1%, we observe an asymmetry of (-8.1±2.1)%. This is in agreement with the standard electroweak theory prediction of (-7.6±0.6)%. The weak-current coupling constants are also reported.

4 data tables

Table 1

SEE PRL 55, 665 FOR DISTRIBUTIONS AT 34.6 GEV AND ABOVE.

Table 2

SEE PRL 55, 665 FOR CROSS SECTION VALUES AND FORWARD BACKWARD ASYMMETRY.

Table 3

No description provided.

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MEASUREMENT OF PI- P ---> PI0 PI0 N AT 25-GEV/C

Apel, W.D. ; Augenstein, K.H. ; Bertolucci, E. ; et al.

Nucl.Phys.B 201 (1982) 197-204, 1982.

Inspire Record 181089 DOI 10.17182/hepdata.17634

The reaction π − p→ π 0 π 0 n has been measured with a 648 channel hodoscope spectrometer for the detection of the four γ's from the π 0 decays. The π 0 π 0 D-wave is fully compatible with the f 0 contribution as it is determined in high-statistics π + π − experiments. The magnitude of the π 0 π 0 S-wave and the cosinus of its phase angle (relative to the known D-wave) are determined from fits to the π 0 π 0 angular distributions. Argand diagrams for the I = 0 amplitude S 0 are given for the range 1000 to 1500 MeV/ c 2 . Two solutions exist. One exceeds the unitarity limit above 1200 MeV/ c 2 . The other remains within the unitarity limit and is nearly elastic up to 1450 MeV/ c 2 . It indicates an S 0 wave resonance around 1300 MeV/ c 2 .

2 data tables

Table 1

No description provided.

Table 2

No description provided.

rivet Analysis
Production of $\pi^0 \pi^0$ and $\pi^0 \eta$ in Photon - Photon Collisions

Edwards, C. ; Partridge, Richard ; Peck, C. ; et al.

Phys.Lett.B 110 (1982) 82-86, 1982.

Inspire Record 168793 DOI 10.17182/hepdata.30959

We investigate the four-photon final state produced in γγ colissions. In the π 0 π 0 channel we observe f(1270) production with predominantly helicity 2 and measure a partial width Γ γγ 2.9 +0.6 −0.4 ± keV (independent of assumptions on the helicity). We observe A 2 (1310) production in the π 0 η channel and find a partial width Γ γγ = 0.77 ± 0.18 ± 0.27 KeV (assuming helicity 2). We give an upper limit for f ≈ ηη .

3 data tables

Table 1

Data read from graph. Systematic error on M is of order of 2% or less.

Table 2

Data read from graph.

Table 3

No description provided.

Diffractive Production of 3 $\pi$ States at 63-{GeV} and 94-{GeV}

The ACCMOR collaboration Daum, C. ; Hertzberger, L. ; Hoogland, W. ; et al.

Nucl.Phys.B 182 (1981) 269-336, 1981.

Inspire Record 156369 DOI 10.17182/hepdata.34314

Diffractive production of the 3 π system has been studied at 63 and 94 GeV using a two magnet spectrometer with high, uniform acceptance. The total number of events used in the analysis is ∼600 000. The A 2 meson is shown to be diffractively produced. The existence of a resonant component in both the 1 + and 2 − enhancements is established and resonance parameters for the corresponding A 1 and A 3 mesons are given. There are several indications in the data of states which would correspond to radial excitations in the quark model.

4 data tables

Table 1

SEE C. DAUM ET AL., PL 89B, 276 (1980) (<a href=http://durpdg.dur.ac.uk/scripts/reacsearch.csh/TESTREAC/red+486> RED = 486 </a>), AND THE RECORD (<a href=http://durpdg.dur.ac.uk/scripts/reacsearch.csh/TESTREAC/red+420> RED = 420 </a>) OF THE GENEVA CONFERENCE PREPRINT, B. ALPER ET AL. (1979).

Table 2

SEE C. DAUM ET AL., PL 89B, 281 (1980) (<a href=http://durpdg.dur.ac.uk/scripts/reacsearch.csh/TESTREAC/red+487> RED = 487 </a>), AND THE RECORD (<a href=http://durpdg.dur.ac.uk/scripts/reacsearch.csh/TESTREAC/red+419> RED = 419 </a>) OF THE GENEVA CONFERENCE PREPRINT, G. THOMPSON ET AL. (1979).

Table 3

SEE C. DAUM ET AL., PL 89B, 285 (1980) (<a href=http://durpdg.dur.ac.uk/scripts/reacsearch.csh/TESTREAC/red+488> RED = 488 </a>), AND THE RECORD (<a href=http://durpdg.dur.ac.uk/scripts/reacsearch.csh/TESTREAC/red+421> RED = 421 </a>) OF THE GENEVA CONFERENCE PREPRINT, B. ALPER ET AL. (1979).

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Direct Photon Production at the $\psi$

Scharre, D.L. ; Alam, M.S. ; Boyarski, A. ; et al.

Phys.Rev.D 23 (1981) 43, 1981.

Inspire Record 153865 DOI 10.17182/hepdata.24079

We present results of a detailed analysis of inclusive direct photon production at the ψ(3095). The direct-photon momentum distribution for x>0.4 is presented and compared with the leading-order quantum-chromodynamic prediction. The total production rate is found to be consistent with theoretical expectations, but the observed momentum distribution is considerably softer. Results of an analysis of some inclusive properties of the hadronic system recoiling against the direct photon are presented. The mean charged-particle and Ks multiplicities are presented as functions of the invariant mass of the hadronic system. These data agree well with the corresponding mean multiplicities measured in e+e− annihilations at center-of-mass energies comparable to the invariant mass of the hadronic system.

4 data tables

Table 1

TOTAL INCLUSIVE PHOTON MOMENTUM SPECTRUM. ERRORS ARE STATISTICAL ONLY.

Table 2

PHOTON SPECTRUM PREDICTED FROM MEASUREMENT OF THE PI0 AND ETA DISTRIBUTIONS. ERRORS INCLUDE BOTH STATISTICAL AND RELATIVE SYSTEMATIC COMPONENTS.

Table 3

INCLUSIVE PI0 MOMENTUM DISTRIBUTION. QUOTED ERRORS ARE STATISTICAL ONLY. OVERALL AND RELATIVE SYSTEMATIC ERRORS ARE LESS THAN 30 PCT AND MAY VARY SLOWLY WITH X.

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