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Investigation of the Reaction $e^+ e^- \to \eta \pi^+ \pi^-$ in the Energy Range Up to 1.4-{GeV}

Druzhinin, V.P. ; Dubrovin, M.S. ; Eidelman, S.I. ; et al.
Phys.Lett.B 174 (1986) 115-117, 1986.
Inspire Record 234174 DOI 10.17182/hepdata.30258

The reaction e + e − → ηπ + π − has been studied with the Neutral Detector in the CM energy range 1.05–1.40 GeV at VEPP-2M. At the maximum energy the cross section exceeds the prediction of the vector dominance with one ϱ(770). The following upper limits for the electron width times branching ratio into ηπ + π − have been obtained for a resonance with a mass of 1.28 GeV and width of 0.08 GeV observed with the Omega-spectrometer at CERN: Λ ee · B ηππ < 9 eV, and for a ϱ′(1250) with a mass of 1.26 GeV and width of 0.125 GeV: Λ ee · B ηππ < 14 eV at 90% confidence level.

1 data table
Table 1

Axis error includes +- 10/10 contribution (RES-DEF(RES=ETA,DEF=530<M(2GAMMA)<570 MEV,BACK=CORRECTED)).


TOTAL, ELASTIC AND INCLUSIVE SINGLE DIFFRACTIVE CROSS-SECTIONS IN ALPHA-ALPHA COLLISIONS AT THE CERN INTERSECTING STORAGE RINGS

Lloyd Owen, D. ; Paternoster, G. ; Patricelli, S. ; et al.
Nucl.Phys.B 274 (1986) 685-706, 1986.
Inspire Record 227125 DOI 10.17182/hepdata.33694

We present measurements of the total interaction cross section and of the single-diffractive dissociation cross section in αα collisions at √ s = 126 GeV. The result obtained for the total cross section, σ tot = (315±18) mb, is a substantial improvement on the precision of earlier measurements. Earlier elastic data were re-analysed, incorporating, through the optical theorem, the present σ tot measurement, resulting in improved determinations of the forward slope, b − t <0.07 = (87±4) GeV −2 , and of the integrated elastic cross section, σ el = (58±6) mb. The single-diffractive differential cross section falls exponentially with momentum transfer at small values of t with a slope b sd = (19.3 ± 0.6) GeV −2 . The integrated single-diffractive cross section is σ sd = (16.6±2.5) mb. The topology of charged tracks resulting from the disintegration of the α in single-diffractive events reveals a two-component distribution. The cross section data are compared with multiple-scattering models.

2 data tables
Table 1

Total cross section by total rate method. Systematic errors included.

Table 2

Reanalysis using data from ISR experiments R-418, and R-807.


Measurement of the Spin Correlation Parameters A(ll) and A(sl) for the Reaction $P P \to D \pi^+$ in the Energy Region 500-{MeV} - 800-{MeV}

Barlow, D.B. ; Saha, A. ; Seth, K.K. ; et al.
Phys.Rev.C 37 (1988) 1977-1986, 1988.
Inspire Record 242361 DOI 10.17182/hepdata.26282

Angular distributions of the spin-correlation parameters Asl and All for the reaction pp→π+d have been measured at pion center-of-mass angles 40°≤θπ+*≤130° at incident energies of 500, 650, and 800 MeV. Additional measurements of All were made at 600, 700, and 750 MeV. The results of the experiment are compared with the predictions of several unified coupled-channel calculations and partial-wave analyses. While the latest partial-wave analyses were found to fit the data reasonably well, all except one of the various model predictions not only do not fit the data well, but also tend to be in disagreement with each other. The data show no clear sign of a need for proposed dibaryon resonances.

9 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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SEARCH FOR THE S MESON IN ANTI-PROTON PROTON INTERACTIONS

Fickinger, W. ; Marino, R. ; Robinson, D.K. ; et al.
Phys.Rev.D 34 (1986) 3332-3342, 1986.
Inspire Record 239036 DOI 10.17182/hepdata.26472

The interaction between antiprotons and protons has been studied in the range 1910 to 1990 MeV center-of-mass energy in a drift-chamber experiment at the Brookhaven Alternating Gradient Synchrotron. The total cross section has been determined at eleven different incident momenta, and the elastic cross section between 8 and 30 deg in the laboratory has been measured with an energy resolution of about 5 MeV. The cross section for annihilation into charged mesons has also been measured, with the same resolution. There is no evidence in any of these channels for the existence of a narrow resonance.

3 data tables
Table 1

Data are for total sample with nuclear physics calculation as described in the paper.

Table 2

Partial elastic cross sections.

Table 3

Partial annihilation cross sections.


Observation of Double $\phi$ Meson Production in the Central Region for the Reactions $\pi^+ P \to \pi^+ (K^+ K^+ K^- K^-$) $P$ and $P P \to P (K^+ K^+ K^- K^-$) $P$ at 85-{GeV}/c

The ATHENS-BARI-BIRMINGHAM-CERN collaboration Armstrong, T.A. ; Bloodworth, I.J. ; Carney, J.N. ; et al.
Phys.Lett.B 166 (1986) 245-248, 1986.
Inspire Record 228698 DOI 10.17182/hepdata.30307

The reactions π + p → π + ( K + K + K − K − ) p and pp → p ( K + K + K − K − ) p in which the K + K + K − K − system is centrally produced have been studied at 85 GeV c . Evidence is found for φφ production. The relative rates for production of φφ , φK + K − and K + K + K − K − have been determined.

1 data table
Table 1

No description provided.


Atomic Beam Measurement of Parity Nonconservation in Cesium

Gilbert, S.L. ; Wieman, Carl E. ;
Phys.Rev.A 34 (1986) 792-803, 1986.
Inspire Record 237319 DOI 10.17182/hepdata.26392

We present a new measurement of parity nonconservation in cesium. In this experiment, a laser excited the 6S→7S transition in an atomic beam in a region of static electric and magnetic fields. The quantity measured was the component of the transition rate arising from the interference between the parity nonconserving amplitude, scrEPNC, and the Stark amplitude, βE. Our results are ImscrEPNC/β=−1.65±0.13 mV/cm and C2p=-2±2, where C2p is the proton-axial-vector–electron-vector neutral-current coupling constant. These results are in agreement with previous less precise measurements in cesium and with the predictions of the electroweak standard model. We give a detailed discussion of the experiment with particular emphasis on the treatment and elimination of systematic errors. This experimental technique will allow future measurements of significantly higher precision.

3 data tables
Table 1

Axis error includes +- 0.0/0.0 contribution (?////THE UNCERTAINTY IS DOMINATED BY THE PURELY STATISTICAL CONTRIBUTION).

Table 2

Axis error includes +- 0.0/0.0 contribution (?////THE UNCERTAINTY IS DOMINATED BY THE PURELY STATISTICAL CONTRIBUTION).

Table 3

Axis error includes +- 0.0/0.0 contribution (?////THE UNCERTAINTY IS DOMINATED BY THE PURELY STATISTICAL CONTRIBUTION).


ATOMIC PARITY VIOLATION MEASUREMENTS IN THE HIGHLY FORBIDDEN (6)S(1/2) - (7)S(1/2) CESIUM TRANSITION. 3. DATA ACQUISITION AND PROCESSING. RESULTS AND IMPLICATIONS

Bouchiat, M.A. ; Guena, J. ; Pottier, L. ; et al.
J.Phys.(France) 47 (1986) 1709-1730, 1986.
Inspire Record 232798 DOI 10.17182/hepdata.38588

This paper completes the detailed presentation of our PV experiment on the 6S1/2 - 7S1/2 transition in Cs. A detailed description of the data acquisition and processing is given. The results of two independent measurements made on ΔF = 0 and ΔF =1 hfs components agree, providing an important cross-check. After a complete reanalysis of systematics and calibration, the precision is slightly improved, leading to the weighted average Im Epv 1/β = - 1.52 ± 0.18 mV/cm. Later results from an independent group agree quite well. With the semi-empirical value β = (26.8 ± 0.8) a30, our result yields Epv1 = (- 0.79 ± 0.10) x 10-11 i |e|a0. Coupled with the atomic calculations, this implies that the weak nuclear charge of Cs is Qw = -68 ± 9. This value agrees with the standard electroweak theory and leads to a weak interaction angle sin2 θ W = 0.21 ± 0.04. The complementarity of these measurements with high energy experiments is illustrated.

3 data tables
Table 1

Revision of the earlier experiment PL 117B, 358. (7s)2S1/2:F=4 --> (6s)2S1/2:F=4 transition.

Table 2

Revision of the earlier experiment PL 134B, 463. (7s)2S1/2:F=3 --> (6s)2S1/2:F=4 transition.

Table 3

Combined of the two above measurements following the philosophy: quadratic sum of the statistical and systematic uncertainties and weighting each result by the squared reciprocal of that uncertainty. (7s)2S1/2 --> (6s)2S1/2 transitions.


Lepton and pion pair production in γγ collisions measured near the threshold at DCI

Courau, A. ; Falvard, A. ; Haissinski, J. ; et al.
Nucl.Phys.B 271 (1986) 86800013 1-20, 1986.
Inspire Record 232808 DOI 10.17182/hepdata.38240

This paper reports a complete analysis of data taken at DCI to measure lepton and pion pair production close to the threshold in two-photon processes: e<sup loc="post">+</sup>e<sup loc="post">−</sup> → e<sup loc="post">+</sup>e<sup loc="post">−</sup>(e<sup loc="post">+</sup>e<sup loc="post">−</sup>, μ<sup loc="post">+</sup>μ<sup loc="post">−</sup>, π<sup loc="post">+</sup>π<sup loc="post">−</sup>). Preliminary results have been previously published including one-half of the total statistics. Final results presented here are in good agreement with QED for lepton pair production. The measured cross section for pion pair production is twice as large as that expected from Born terms only — a two standard deviation effect.

1 data table
Table 1

Normalised to number of observed electron pairs. Fully corrected for acceptance, radiative effects etc.


DETERMINING INELASTIC INTERACTION CROSS-SECTIONS FOR NUCLEONS AND PIONS INCIDENT ON CARBON AND LEAD NUCLEI AT 0.5-TEV - 5-TEV

Avakian, V.V. ; Gevorkian, S.P. ; Zhamkochian, V.M. ; et al.
Bull.Russ.Acad.Sci.Phys. 50N11 (1986) 4-7, 1986.
Inspire Record 242221 DOI 10.17182/hepdata.41509

None

1 data table
Table 1

No description provided.


SEARCH FOR EXOTIC BARYON RESONANCES WITH ISOSPIN I = 5/2 IN pi+ p REACTIONS AT 3.94-GeV/c pi+ MESON MOMENTA

Arefev, A.V. ; Bayukov, Yu.D. ; Grishuk, Yu.G. ; et al.
ITEP-86-150, 1986.
Inspire Record 234870 DOI 10.17182/hepdata.40112

None

1 data table
Table 1

No description provided.