Gerhards, R.
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Measurement of the cross-section for production of two isolated prompt photons in anti-p p collisions at s**(1/2) = 1.8-TeV

The CDF collaboration Abe, F. ; Albrow, Michael G. ; Amidei, Dante E. ; et al.
Phys.Rev.Lett. 70 (1993) 2232-2236, 1993.
Inspire Record 343802 DOI 10.17182/hepdata.19755

We present measurements from events with two isolated prompt photons in p¯p collisions at √s =1.8 TeV. The differential cross section, measured as a function of transverse momentum (PT) of each photon, is about 3 times what next-to-leading-order QCD calculations predict. The cross section for photons with PT in the range 10–19 GeV is 86±27(stat)−23+32(syst) pb. We also study the correlation between the two photons in both azimuthal angle and PT. The magnitude of the vector sum of the transverse momenta of both photons, KT=‖PT1+PT2‖, has a mean value of 〈KT〉=5.1±1.1 GeV.

5 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

Vector sum of the photons transvserse momenta.. Errors contain both statistics and systematics.. Data read from plots.

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Dependence of spectra and cross-sections yield of proton at the energy more than 0.4-GeV at fixed angles on atomic weights of colliding nuclei in nucleus-nucleus interactions

Agakishiev, G.N. ; Bekmirzaev, R. ; Kanarek, T. ; et al.
Phys.Atom.Nucl. 56 (1993) 1397-1405, 1993.
Inspire Record 345328 DOI 10.17182/hepdata.17221

None

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Observation of xi(c)0 semileptonic decay

The ARGUS collaboration Albrecht, H. ; Cronstrom, H.I. ; Ehrlichmann, H. ; et al.
Phys.Lett.B 303 (1993) 368-376, 1993.
Inspire Record 342661 DOI 10.17182/hepdata.6178

Observation of the semileptonic decay of the charmed baryon in the decay channel has been made using the ARGUS detector at the e + e − storage ring DORIS II at DESY. The cross section times branching ratio was found to be .

6 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

Averaging the above two results.

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rivet Analysis
Studies of strong and electroweak interactions using final state photon emission in hadronic Z0 decays

The OPAL collaboration Acton, P.D. ; Alexander, G. ; Allison, John ; et al.
Z.Phys.C 58 (1993) 405-418, 1993.
Inspire Record 343181 DOI 10.17182/hepdata.52379

The cross section and jet rates ofZ0 decays into photons and quarks are compared with matrix element Monte Carlos ofO(ααs). Good agreement is found between data and theoretical predic

4 data tables
Table 1

Corrected number of hadronc events that have a final state photon per 1000 multhadronic Z0 decays, using the E0 scheme.

Table 2

Corrected number of hadronc events that have a final state photon per 1000 multhadronic Z0 decays, using the Durham scheme.

Table 3

Corrected number of events that have a final state photon with 1, 2, 3, or more jets per 1000 multhadronic Z0 decays, using the E0 scheme.

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rivet Analysis
Inclusive production of charged pions, kaons and protons in upsilon (4S) decays

The ARGUS collaboration Albrecht, H. ; Cronstrom, H.I. ; Ehrlichmann, H. ; et al.
Z.Phys.C 58 (1993) 191-198, 1993.
Inspire Record 340894 DOI 10.17182/hepdata.14424

Using the detector ARGUS at thee+e− storage ring DORIS II, we have investigated inclusive momentum spectra of charged pions, kaons, and protons from decays of the υ(4S) meson. The kaon spectra have been measured in two independent ways, by coherently exploiting the detector's particle identification capabilities, and by detecting decays in-flight. The extracted mean multiplicities for charged hadrons are 7.17±0.05±0.14 pions, 1.56±0.03±0.05 kaons and 0.110±0.010±0.007 protons per υ(4S) decay, where pions and protons fromKso and Δ decays have been subtracted.

11 data tables
Table 1

Inclusive pion spectrum from UPSI(4S) decays.

Table 2

Inclusive pion spectrum from UPSI(4S) decays with KS and LAMBDA decay particles included.

Table 3

Inclusive kaon spectrum from UPSI(4S) decays.

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Angular dependence of analyzing power in n p elastic scattering between 0.312-GeV and 1.1-GeV

Ball, J. ; Chesny, P. ; Combet, M. ; et al.
Nucl.Phys.A 559 (1993) 489-510, 1993.
Inspire Record 341321 DOI 10.17182/hepdata.36590

We present a total of 427 np analyzing power data points in a large angular interval at 12 energies between 0.312 and 1.10 GeV. The SATURNE II polarized beam of free monochromatic neutrons was scattered either on the Saclay frozen-spin polarized proton target or on CH 2 and C targets. Present results are compared with existing elastic and quasieleastic data.

18 data tables
Table 1

Results of the analyzing power for n p scattering at 0.312 GeV. The CH2 target was used.

Table 2

Results of the analyzing power for n p scattering at 0.363 GeV. The CH2 target was used.

Table 3

Results of the analyzing power for n p scattering at 0.800 GeV.

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Measurements of the electric and magnetic form-factors of the neutron from Q**2 = 1.75-GeV/c**2 to 4-GeV/c**2

Lung, A. ; Stuart, L.M. ; Bosted, Peter E. ; et al.
Phys.Rev.Lett. 70 (1993) 718-721, 1993.
Inspire Record 342252 DOI 10.17182/hepdata.19739

Quasielastic e-d cross sections have been measured at forward and backward angles. Rosenbluth separations were done to obtain RL and RT at Q2=1.75, 2.50, 3.25, and 4.00 (GeV/c)2. The neutron form factors GEn and GMn have been extracted using a nonrelativistic model. The sensitivity to deuteron wave function, relativistic corrections, and models of the inelastic background are reported. The results for GMn are consistent with the dipole form, while GEn is consistent with zero. Comparisons are made to theoretical models based on vector meson dominance, perturbative QCD, and QCD sum rules, as well as constituent quarks.

2 data tables
Table 1

Magnetic form factors.

Table 2

Electric form factors.


Total photoproduction cross-section measurement at HERA energies

The H1 collaboration Ahmed, T. ; Andreev, V. ; Andrieu, B. ; et al.
Phys.Lett.B 299 (1993) 374-384, 1993.
Inspire Record 340891 DOI 10.17182/hepdata.45139

We present first results on the total photoproduction cross section measurement with the H1 detector at HERA. The data were extracted from low Q 2 collisions of 26.7 GeV electrons with 820 GeV protons. The γp total cross section has been measured by two independent methods in the γp center of mass energy range from 90 to 290 GeV. For an average center of mass energy of 195 GeV a value of σ tot ( γp ) = 159 ± 7 (stat.) ± 20 (syst.) μb was obtained.

2 data tables
Table 1

Data from tagged sample.

Table 2

Data from untagged sample.


Study of electron-neutrino electron elastic scattering at LAMPF

Allen, R.C. ; Chen, H.H. ; Doe, P.J. ; et al.
Phys.Rev.D 47 (1993) 11-28, 1993.
Inspire Record 33287 DOI 10.17182/hepdata.22728

Neutrino-electron elastic scattering was observed with a 15-ton fine-grained tracking calorimeter exposed to electron neutrinos from muon decay at rest. The measured νee−→νee− elastic scattering rate of 236±35 events yields the total elastic scattering cross section 10.0±1.5(stat)±0.9(syst)×10−45 cm2×[Eν (MeV)], and a model-independent measurement of the strength of the destructive interference between the charged and neutral currents, I=−1.07±0.21, that agrees well with the standard model (SM) prediction I=−1.08. The agreement between the measured electroweak parameters and SM expectations is used to place limits on neutrino properties, such as neutrino flavor-changing neutral currents and neutrino electromagnetic moments. Limits are placed on the masses of new bosons that interact with leptons: for a neutral tensor boson, MT>105 GeV; for a neutral (pseudo)scalar boson, MP,S>47 GeV; for a charged Higgs boson, Mχ+>87 GeV; and for a purely left-handed charged (neutral) vector boson, Mx>239 (119) GeV.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Multiplicity distributions in small phase space domains in central nucleus-nucleus collisions

The NA35 collaboration Bächler, J. ; Bartke, J. ; Białkowska, H. ; et al.
Z.Phys.C 57 (1993) 541-550, 1993.
Inspire Record 342658 DOI 10.17182/hepdata.14492

Multiplicity distributions of negatively charged particles have been studied in restricted phase space intervals for central S+S, O+Au and S+Au collisions at 200 GeV/nucleon. It is shown that multiplicity distributions are well described by a negative binomial form irrespectively of the size and dimensionality of phase space domain. A clan structure analysis reveals interesting similarities between complex nuclear collisions and a simple partonic shower. The lognormal distribution agrees reasonably well with the multiplicity data in large domains, but fails in the case of small intervals. No universal scaling function was found to describe the shape of multiplicity distributions in phase space intervals of varying size.

13 data tables
Table 1

Multiplicity distribution analysed in 1D for M = 4.

Table 2

Multiplicity distribution analysed in 2D for M = 16.

Table 3

Multiplicity distribution analysed in 3D for M = 64.

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