D' Angelo, S.
DSIG/DOMEGA
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Real to Imaginary Ratio of the $\bar{p} p$ Forward Elastic Scattering Amplitude in the Momentum Range Between 180-{MeV}/$c$ and 590-{MeV}/$c$

Bruckner, W. ; Dobbeling, H. ; Guttner, F. ; et al.
Phys.Lett.B 158 (1985) 180-185, 1985.
Inspire Record 213992 DOI 10.17182/hepdata.30392

The real-to-imaginary ratio of the p p forward elastic scattering amplitude has been measured at the LEAR facility of CERN by the Coulomb-nuclear interference method at seven beam momenta between 181 and 590 MeV/ c . The ratio is positive at 590 MeV/ c , becomes negative below 500 MeV/ c , reaches a minimum at 260 MeV/ c and then crosses zero again at about 230 MeV/ c .

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Measurements of Tau Lepton Production and Decay

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Lackas, W. ; et al.
Z.Phys.C 28 (1985) 1, 1985.
Inspire Record 213241 DOI 10.17182/hepdata.16019

We have studied 419 τ pair events produced in the reactione+e−→τ+ τ− at a c.m. energy of 34.6 GeV. We measure the cross section and angular distribution, as well as the decay branching ratios. The production characteristics are consistent with the Standard Electroweak Model predictions of γ andZ0 interference. The branching ratios are generally consistent with the τ decaying according to standard weak interaction principles, but we observe somewhat more decays resulting in single charged hadrons plus neutrals than are predicted by present theory.

3 data tables
Table 1

Corrected for radiative effects.

Table 2

Measured cross section relative to Standard Model Prediction.

Table 3

Asymmetry based on fits to angular distribution.


PROTON COMPTON SCATTERING AT BACKWARD ANGLES IN THE ENERGY RANGE FROM 400-MeV TO 1050-MEV

Wada, Y. ; Egawa, K. ; Imanishi, A. ; et al.
Nucl.Phys.B 247 (1984) 313-338, 1984.
Inspire Record 215373 DOI 10.17182/hepdata.33842

Differential cross sections of proton Compton scattering have been measured in the energy range between 400 MeV and 1050 MeV at C.M.S. angles of 150° and 160°.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


DIFFERENTIAL CROSS-SECTIONS FOR PROTON COMPTON SCATTERING AT INCIDENT PHOTON ENERGIES BETWEEN 900-MeV AND 1150-MEV

Ishii, T. ; Egawa, K. ; Imanishi, A. ; et al.
Nucl.Phys.B 254 (1985) 458-474, 1985.
Inspire Record 218918 DOI 10.17182/hepdata.33788

Differential cross sections of proton Compton scattering have been measured in the angular range between 50° and 130° at incident photon energies from 900 MeV to 1150 MeV. A sharp dip in the angular distribution found by a Bonn group at 110° in the photon energy region around 900 MeV is not observed in the present measurement. A new dip-bump structure is found at photon energies above 1050 MeV, which is similar to that for pion-nucleon scattering.

12 data tables
Table 1

No description provided.

Table 2

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Table 3

No description provided.

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REACTION ANTI-P C-12 ---> ANTI-N X AT 590-MEV/C

Nakamura, K. ; Fujii, T. ; Kageyama, T. ; et al.
Phys.Rev.C 31 (1985) 1853-1856, 1985.
Inspire Record 220552 DOI 10.17182/hepdata.26214

The antineutron angular distribution in the reaction p¯C→n¯X was measured at 590 MeV/c. The shape of the distribution is found to be similar to that of the elementary process p¯p→n¯n, which indicates that the quasi-free process is the dominant mechanism for p¯C→n¯X. The antineutron production cross section per bound proton in the carbon nucleus is 0.14 times that for a free proton.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


OBSERVATION OF AN ENHANCEMENT IN ANTI-P P ---> PI+ PI- AND ANTI-P P ---> K+ K- CROSS-SECTIONS AT ANTI-P MOMENTUM OF APPROXIMATELY 500-MEV/C

Tanimori, T. ; Fujii, T. ; Kageyama, T. ; et al.
Phys.Rev.Lett. 55 (1985) 1835-1838, 1985.
Inspire Record 221965 DOI 10.17182/hepdata.20293

The reactions p¯p→π+π− and K+K− have been studied at 390, 490, 590, 690, and 780 MeV/c. An enhancement of about 150 μb has been observed in the cross sections of both reactions at the same beam momentum of 490 MeV/c. If this structure is interpreted as a meson resonance, it has a mass of 1940 ± 20 MeV and a width of less than 40 MeV.

11 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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NEUTRAL PION PHOTOPRODUCTION ON THE DEUTERON

Imanishi, A. ; Ishii, T. ; Kato, S. ; et al.
Phys.Rev.Lett. 54 (1985) 2497-2500, 1985.
Inspire Record 220232 DOI 10.17182/hepdata.20385

Large-angle cross sections for γd→π0d are systematically measured in the photon energy range between 500 and 1000 MeV. A good fit is obtained by use of a Glauber-model calculation which includes the dibaryon resonances F33(2.26) and G41(2.51), but the fit has an unusual nature in the role of resonance and nonresonance contributions.

2 data tables
Table 1

Liquid hydrogen target for final calibration.

Table 2

LIQUID DEUTERIUM TARGET.


Tests of the Standard Model With Lepton Pair Production in $e^+ e^-$ Reactions

The PLUTO collaboration Berger, Christoph ; Deuter, A. ; Genzel, H. ; et al.
Z.Phys.C 27 (1985) 341, 1985.
Inspire Record 207950 DOI 10.17182/hepdata.1917

The differential cross section of the reactione+e−→e+e− at a c.m. energy of 34.7 GeV has been measured. The result, together with our previously measurede+e−→α+α− data, are compared with the standard model predictions. We obtain for the weak neutral current couplings the valuesgv2=0.09×0.06,ga2=0.38×0.08. A fit of the Weinberg mixing angle gives the valuegv2=0.09×0.06,ga2=0.038×0.08. The data are also used to set limits on possible deviations from the pointlike structure of leptons. An upper limit for thee+e− coupling to a heavy spin 0 boson is also given.

3 data tables
Table 1

Fully corrected results for Bhabha scattering.

Table 2

The differential cross section for Bhabha scattering.

Table 3

??? CONSTANTS ???.


The Production and Decay of Tau Leptons in $e^+ e^-$ Annihilation at {PETRA} Energies

The TASSO collaboration Althoff, M. ; Braunschweig, W. ; Kirschfink, F.J. ; et al.
Z.Phys.C 26 (1985) 521, 1985.
Inspire Record 205120 DOI 10.17182/hepdata.16121

We have observed τ pair production at average CM energies of 13.9, 22.3, 34.5 and 43.1 GeV. The cross-sections are consistent with QED, the cut off parameters beingΛ+>161 GeV andΛ−169 GeV (95% CL). The topological branching fraction of the τ to 1 charged particle,B1, is 0.847±0.011 (stat)−0.013+0.016(syst) and no decays to 5 charged particles were observed resulting inB5<0.007 (95% CL). Within the 3 charged track final stateB(τ−→π−π+π−v)/(B(τ−→π−π+π−v)+B(τ−→π−π+π−π0v))=0.37−0.20+0.35

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Photon Pair Production by $e^+ e^-$ Annihilation and Search for Supersymmetric Photinos at Energies > 40-{GeV}

The TASSO collaboration Althoff, M. ; Braunschweig, W. ; Kirschfink, F.J. ; et al.
Z.Phys.C 26 (1984) 337, 1984.
Inspire Record 204486 DOI 10.17182/hepdata.16194

None

2 data tables
Table 1

No description provided.

Table 2

No description provided.