Derrick, M.
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Proton - Anti-proton Annihilations at Rest Into $\pi^0 \omega$, $\pi^0 \eta$, $\pi^0 \gamma$, $\pi^0 \pi^0$, and $\pi^0 \eta^\prime$

Backenstoss, G. ; Hasinoff, M. ; Pavlopoulos, P. ; et al.
Nucl.Phys.B 228 (1983) 424-438, 1983.
Inspire Record 189897 DOI 10.17182/hepdata.33919

Proton-antiproton annihilations at rest in liquid hydrogen were investigated through the inclusive γ spectrum, related to the annihilation. The high-energy part of the spectrum was used to deduce branching ratios for the so far unobserved annihilation channels: R( p p →π 0 ω) = (2.38 ± 0.65)% , R( p p → π 0 η) = (0.82 ± 0.10% , R p p →π 0γ) = (0.015 ± 0.007)% , and R( p p → π 0 π 0 = (0.06 ± 0.04)% . An upper limit for the π 0 η ′ channel was deduced to be R( p p → π 0 η ′ ) < 1.1% .

1 data table
Table 1

RESULTS ALSO INCLUDE AN UNKNOWN PARTICLE X WHOSE BRANCHING RATIO IS 1.19 +- 0.25 (DSYS = 0.44) PCT.


rivet Analysis
>A Measurement of $e^+ e^- \to \bar{p} p$ for 1975-{MeV} $\le \sqrt{s} \le$ 2250-{MeV}

Bisello, D. ; Limentani, S. ; Nigro, M. ; et al.
Nucl.Phys.B 224 (1983) 379, 1983.
Inspire Record 190558 DOI 10.17182/hepdata.33935

The e + e − → p p cross section has been measured in the energy interval (1975 ⩽ 2 E ⩽ 2250) MeV for |cos θ | < 0.7. The measurement is based on ∼ 100 events, thus improving by a factor 3 on the previous existing statistics in this energy interval. The form factor | G | 2 is given as a function of energy under the assumption | G E | = | G M |. We also give the first measurement of the differential cross section, averaged over the energy interval, and estimate the ratio G M |/| G E | from it.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Search for New S Anti-s States in the $K^-$ Induced $K^+ K^-$ System

Armstrong, T. ; Baubillier, M. ; Beusch, W. ; et al.
Nucl.Phys.B 224 (1983) 193-217, 1983.
Inspire Record 190033 DOI 10.17182/hepdata.33934

Results from the first PWA of the K + K − system produced by incident K − , are presented in the mass range from the threshold to 1.70 GeV. In the P and D waves only the φ and f′ mesons are observed and their production mechanism studied. A broad S wave peaking at 1.4 GeV is observed but the lack of information about its phase makes the search for new 0 ++ mesons inconclusive.

4 data tables
Table 1

ASSUMING BRANCHING RATIO 0.486 FOR PHI --> K+ K-.

Table 2

No description provided.

Table 3

No description provided.

More…

Elastic and total cross-section measurement at the CERN proton-antiproton collider

The UA1 collaboration Arnison, G. ; Astbury, A. ; Aubert, Bernard ; et al.
Phys.Lett.B 128 (1983) 336, 1983.
Inspire Record 190339 DOI 10.17182/hepdata.30668

Proton-antiproton elastic scattering at CM energy 540 GeV has been studied in the t -range 0.04 < − t < 0.45 GeV 2 . The data are well fitted by the form exp ( bt ) with b = 17.1 ± 1.0 GeV −2 for | t | = 0.04 − 0.18 GeV su 2 and b = 13.7 ± 0.2 ± 0.2 GeV −2 for | t | = 0.21−0.45 GeV 2 . A luminosity measurement combined with the optical theorem gives σ tot = 67.6 ± 5.9 ± 2.7 mb and σ e1 / σ tot = 0.209 ± 0.018 ± 0.008.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

ELASTIC RATIO ASSUMES RHO=0.


Differences in Leading Baryon Production From $p \bar{p}$ and $p p$ Collisions With $\sqrt{s}=31$-{GeV} at the {CERN} {ISR}

Chauvat, P. ; Cousins, R.D. ; Erhan, S. ; et al.
Phys.Lett.B 127 (1983) 384-388, 1983.
Inspire Record 190333 DOI 10.17182/hepdata.30717

Significant differences are observed between forward-produced Δ ++ (1232) and Λ 0 's in pp interactions and their corresponding anti-particles in p p interactions, as expected from quark counting and single q q annihilation. A possible relationship between these results and the p p -pp total cross section difference is discussed.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Observation of Scalar $G(1590)$ Meson Decaying Into $\eta \eta$

The Serpukhov-Brussels-Annecy(LAPP) collaboration Binon, F.G. ; Bricman, C. ; Gouanere, M. ; et al.
Yad.Fiz. 38 (1984) 934-944, 1984.
Inspire Record 191942 DOI 10.17182/hepdata.37464

None

1 data table
Table 1

No description provided.


Measurement of the Processes $e^+ e^- \to e^+ e^-$ and $e^+ e^- \to \gamma \gamma$ at {PETRA}

The JADE collaboration Bartel, W. ; Becker, L. ; Bowdery, C. ; et al.
Z.Phys.C 19 (1983) 197, 1983.
Inspire Record 191231 DOI 10.17182/hepdata.45206

Cross sections for the reactionse+e−→e+e− (Bhabha scattering) ande+e−→γγ are measured for center-of-mass (c.m.) energies\(\sqrt s \) between 12.0 and 34.6 GeV. The results agree with the predictions of Quantum Electrodynamics (QED) and the cut-off parameters are determined. From Bhabha scattering at the highest energy,\(\left\langle {\sqrt s } \right\rangle= 34.6 GeV\), the 1 δ limits 0.12

3 data tables
Table 1

Total cross sections.

Table 2

Angular distribution.

Table 3

Angular distribution.


Limits on $J/\psi$ and $\Upsilon$ Production in $e^+ e^-$ Interactions at $\sqrt{s}=29$-{GeV}

Matteuzzi, C. ; Abrams, G.S. ; Amidei, D. ; et al.
Phys.Lett.B 129 (1983) 141-144, 1983.
Inspire Record 189580 DOI 10.17182/hepdata.30662

A search has been made for the inclusive production of J ψ (3.1) and ϒ (9.4) mesons in e + e − interactions at 29 GeV, via their decay into two leptons. No signal is observed in the J ψ region, nor in the ϒ region. The limits on the cross sections are σ ( e + e − → ψX ) < 4.4 × 10 −36 cm 2 , and σ ( e + e − → ϒX ) < 4.7 × 10 −36 cm 2 . The same data yield limits on the branching ratios for the b quark BR ( b → ψX ) < 4.9% and BR ( b → ℓ + ℓ − X ) < 0.8%.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


CHARM PHOTOPRODUCTION CROSS-SECTION AT 20-GeV

Abe, K. ; Bacon, T.C. ; Ballam, Joseph ; et al.
Phys.Rev.Lett. 51 (1983) 156, 1983.
Inspire Record 189662 DOI 10.17182/hepdata.20508

Forty-seven charm events have been observed in an exposure of the SLAC Hybrid Facility bubble chamber to a 20-GeV backward-scattered laser beam. Thirty-seven events survive all the necessary cuts imposed. Based on this number the total charm cross section is calculated to be 63−28+33 nb.

1 data table
Table 1

No description provided.


The Reaction $\gamma p \to p \omega \pi^+ \pi^-$ for Photon Energies of 25-{GeV} - 50-{GeV}

The Omega Photon collaboration Atkinson, M. ; Axon, T.J. ; Barberis, D. ; et al.
Nucl.Phys.B 229 (1983) 269-283, 1983.
Inspire Record 189045 DOI 10.17182/hepdata.33921

Measurements of the reaction γ p → p ωπ + π − are reported for photon energies 25–50 GeV. Particular attention is paid to ωπ + π − masses < 2 GeV. A search is made for ω′ or φ′ partners of the ϱ′(1600). Evidence is presented against the existence of narrow states and against the production of a broad state by an s -channel helicity conserving mechanism.

1 data table
Table 1

No description provided.