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K0 Production in e+ e- Annihilation

Luth, V. ; Pierre, F. ; Abrams, G.S. ; et al.

Phys.Lett.B 70 (1977) 120, 1977.

Inspire Record 119729 DOI 10.17182/hepdata.27537

The production of enutral kaons in e + e − annihilation has been measured for c.m. energies between 3.4 GeV and 7.6 GeV. Near 4 GeV the inclusive K S cross section shows an increase and structure similar to total hadron production. Roughly 40–45% of all hadronic final states contain kaons, except at 4.028 GeV and 4.415 GeV, where a significantly larger kaon fraction is observed.

2 data tables

Table 1

No description provided.

Table 2

THIS IS TWICE THE MEASURED KS CROSS SECTION. THE ERRORS ARE STATISTICAL ONLY. THERE IS 15 PCT ABSOLUTE NORMALIZATION ERROR, PLUS POSSIBLY SOME ENERGY DEPENDENT ERROR. THE DATA ARE NOT EQUALLY SPACED IN THE ENERGY INTERVALS.

rivet Analysis
Observation of a Resonance in e+ e- Annihilation Just Above Charm Threshold

Rapidis, Petros A. ; Gobbi, B. ; Luke, D. ; et al.

Phys.Rev.Lett. 39 (1977) 526, 1977.

Inspire Record 119979 DOI 10.17182/hepdata.20971

We observe a resonance in the total cross section for hadron production in e+e− annihilation at a mass of 3772±6 MeV/c2 having a total width of 28±5 MeV/c2 and a partial width to electron pairs of 370±90 eV/c2.

2 data tables

Table 1

BEFORE ANY RADIATIVE CORRECTIONS.

Table 2

AFTER APPLYING ALL RADIATIVE CORRECTIONS.

Study of the Reaction K- p --> anti-K0 n at Momenta of 25-GeV/c and 40-GeV/c

The Serpukhov-CERN collaboration Apel, W.D. ; Bertolucci, E. ; Donskov, S.V. ; et al.

Nucl.Phys.B 129 (1977) 275, 1977.

Inspire Record 120460 DOI 10.17182/hepdata.35232

Measurements were made of the differential cross sections for the charge exchange of K − mesons on protons at momenta of 25 and 40 GeV/ c using a high-precision spectrometer with no magnetic field. In the range 5–40 GeV/ c the reaction cross section follows a power-law dependence p K − −1.52 . In the snall momentum transfer region (− t ⪅ m π 2 ) a minimum is observed, similar to that discovered at lower energies. The differential cross sections t = 0 are considerably less than those predicted by the Regge-pole model. The parameters of the effective trajectory are determined.

2 data tables

Table 1

Table 2

Backward Production of a Spin Parity 1+ rho pi Enhancement at 1.04-GeV

The Amsterdam-CERN-Nijmegen-Oxford collaboration Gavillet, P. ; Berge, J.P. ; Ferrando, A. ; et al.

Phys.Lett.B 69 (1977) 119, 1977.

Inspire Record 120469 DOI 10.17182/hepdata.27551

A spin-parity 1 + ϱπ enhancement is observed for the 3π mass spectrum in the reaction K − p → Σ − π + π + π − where events with a small (K − → Σ − ) momentum transfer are selected. The mass (1040 MeV) and width (230 MeV) of this enhancement are reminiscent of the A 1 → ϱπ bump which has mainly been observed in the diffractive-like processes. The cross section for this enhancement at 4.15 GeV/ c incident K − momentum is (3.6 ± 0.5) μ b.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

Measurements of the Total Cross-Section Difference and the Parameter C(LL) in p p Scattering with Longitudinally Polarized Beam and Target

Auer, I.P. ; Beretvas, A. ; Colton, E. ; et al.

Phys.Lett.B 70 (1977) 475-478, 1977.

Inspire Record 5342 DOI 10.17182/hepdata.27516

We have measured the difference between the pp total cross-sections for parallel and anti-parallel longitudinal spin states at beam momenta of 3 and 6 GeV/ c . These results, combined with our previous measurements, at lower momenta, are useful in clarifying a striking structure appearing at around 1.5 GeV/ c . We have also measured for the first time, the spin-spin correlation parameter C LL ( t ) in pp elastic scattering at 6 GeV/ c . We observe evidence for an exchange with A 1 -like quantum-numbers.

4 data tables

Table 1

THE NEW DATA ON THE LONGITUDINAL CROSS SECTION DIFFERENCE, SIG(NAME=CLL) AT 3 AND 6 GEV ARE INCLUDED IN THE RECORD OF I. P. AUER ET AL., PL 67B, 113 (1977).

Table 2

NOTE: HIGHER -T DATA ARE BEING ANALYSED. PUBLISHED GRAPH HAS LARGER ERRORS.

Table 3

THESE NUMBERS APPEAR TO UPDATE THOSE REPORTED IN I. P. AUER ET AL., PRL 37, 1727 (76). NOTE: DATA MAY HAVE SMALLER ERROR BARS IN THE FINAL ANALYSIS.

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Some Three-Body Final States in K- p Reactions at 14.3-GeV/c

Wohl, C.G. ; Barloutaud, R. ; Borg, A. ; et al.

Nucl.Phys.B 132 (1978) 401-428, 1978.

Inspire Record 5385 DOI 10.17182/hepdata.35160

We present experimental results on a number of K − p reactions at 14.3 GeV/ c that have three bodies in the final state. The final states are K − ω p , K − π p , Λπ + π − , Λ K + K − , Λp p , K ∗ − ω p , Λ(1520) K + K − and Λ(1520) p p . Whenever, with one exception explained by the Zweig rule, there is a K − or a proton in the final state, there is a diffractive-like threshold enhancement in the mass spectrum of the two recoiling particles. These enhancements account for a large fraction of the events in all but the Λπ + π − final state, where they cannot occur, and which is dominated by resonance production. We find evidence for the Q 1 (1300) decaying into K − ω .

1 data table

Table 1

THE DIFFRACTION DISSOCIATION CROSS SECTIONS ARE FOR DIFFRACTIVE THRESHOLD ENHANCEMENTS IN THE TWO-BODY MASS SPECTRA (WITHIN 500 MEV CM ENERGY OF THRESHOLD).

Baryon Exchange in the Reaction pi- p --> n*0 pi0 at 9-GeV/c and 12-GeV/c

Rouge, A. ; de Rosny, G. ; Fleury, P. ; et al.

Phys.Lett.B 69 (1977) 115-118, 1977.

Inspire Record 5224 DOI 10.17182/hepdata.27540

In π − p interactions at 9 GeV/ c and 12 GeV/ c , the forward production of N ∗ 1680 and N ∗ 1520 has been observed with features of nucleon exchange. The production of Δ1232 is strongly suppressed.

2 data tables

Table 1

No description provided.

Table 2

SLOPE ABOUT 6 GEV**-2 FOR SMALL U AND EVIDENCE FOR CHANGE OF SLOPE NEAR -U = 0.15 GEV**2.

Evidence for Two Narrow p anti-p Resonances at 2020-MeV and 2200-MeV

The CERN-College de France-Ecole Poly-Orsay collaboration Benkheiri, P. ; Boucrot, J. ; Bouquet, B. ; et al.

Phys.Lett.B 68 (1977) 483, 1977.

Inspire Record 119491 DOI 10.17182/hepdata.27541

From the study of the reaction π − p→p F p p π − using a fast proton (p F ) trigger device in the CERN Omega spectrometer, we find evidence for two narrow p p states produced mainly in association with a Δ° (1232) and a N° (1520). The statistical significance of each peak is greater than 6 standard deviations. Masses and natural widths of these resonances are respectively M = 2020 ± 3 MeV , Λ 1 = 24 ± 12 MeV and M 2 = 2204 ± 5 MeV, Λ 2 = 16 −16 +20 MeV. Our data are consistent with a small production of the narrow ∼ 1935 MeV resonance already reported. Production cross sections for these new p p resonances are given.

1 data table

Table 1

ERRORS TAKE INTO ACCOUNT STATISTICAL ERRORS AND BACKGROUND SUBTRACTION UNCERTAINTY BUT NOT ACCEPTANCE CORRECTIONS UNCERTAINTY OF 15 PCT.

The Low Mass K pi System in K- p --> anti-K pi n Reactions at 14.3-GeV/c

Spiro, M. ; Barloutaud, R. ; Borg, A. ; et al.

Nucl.Phys.B 125 (1977) 162-188, 1977.

Inspire Record 5199 DOI 10.17182/hepdata.35407

We present experimental results and a partial-wave analysis of the low-mass ( K π) 0 systems produced in the reactions K − p → K π N at 14.3 GeV/ c . The main results concern the production mechanisms of the K ∗ (890) and K ∗ (1420) . We also extract the s-wave component of the K π system as a function of mass.

5 data tables

Table 1

THE ERRORS QUOTED (EXCEPT FOR THE FIRST REACTION) ARE MAINLY AN ESTIMATE OF THE SYSTEMATIC UNCERTAINTIES.

Table 2

No description provided.

Table 3

No description provided.