Baldi, R.
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Measurement of the Two Photon Reaction $\gamma \gamma \to \pi^+ \pi^- \pi^+ \pi^-$ at Large Values of $Q^2$

The TASSO collaboration Braunschweig, W. ; Gerhards, R. ; Kirschfink, F.J. ; et al.
Z.Phys.C 41 (1988) 353-357, 1988.
Inspire Record 250570 DOI 10.17182/hepdata.15557

The process γγ→π+π−π+π− has been investigated in reactions of the typee+e−→e+e−π+π−π+π− in the single tag mode. The range of the four momentum squared of one of the virtual photons was 0.28 GeV2/c2≦Q2≦3.6 GeV2/c2, the average being 〈Q2〉=0.92 GeV2/c2; the other photon was quasi real. The reaction is mainly described by the channels γγ→ρ0ρ0 and γγ→4π (phase space), occuring with about equal probability. TheQ2-dependence of the cross section is in agreement with the ρ form factor.

2 data tables
Table 1

Data read from graph.. Additional overall systematic error 25%.

Table 2

Data read from graph.. Additional overall systematic error 25%.. The Q**2 approx 0 datum is deduced from the earlier TASSO paper, Brandelik et al, Phys. Lett. 97B(1980)448, (<a href=http://durpdg.dur.ac.uk/scripts/reacsearch.csh/TESTREAC/red+1151> RED = 1151 </a>) on rho0 rho0 production.


Total Neutrino and Anti-neutrino Charged Current Cross-section Measurements in 100-{GeV}, 160-{GeV} and 200-{GeV} Narrow Band Beams

Berge, J.P. ; Blondel, A. ; Bockmann, P. ; et al.
Z.Phys.C 35 (1987) 443, 1987.
Inspire Record 246156 DOI 10.17182/hepdata.15709

Neutrino and antineutrino total charged current cross sections on iron were measured in the 100, 160, and 200 GeV narrow band beams at the CERN SPS in the energy range 10 to 200 GeV. Assuming σ/E to be constant, the values corrected for non-isoscalarity are σv/E = (0.686 ± 0.019) * 10−38 cm2/ (GeV · nucleon) and σv/E = (0.339 ± 0.010) * 10−38 cm2/ (GeV·nucleon). Between 50 and 150 GeV no energy dependence of σ/E was observed within ±3% for neutrino and ±4% for antineutrino interactions.

5 data tables
Table 1

Measured charged current total cross section.

Table 2

Measured charged current total cross section.

Table 3

No description provided.

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Determination of the Real Part of the Isospin Even Forward Scattering Amplitude of Pion Nucleon Scattering at 55-{MeV} as a Test of Low-energy Quantum Chromodynamics

Wiedner, U. ; Goring, K. ; Jaki, J. ; et al.
Phys.Rev.Lett. 58 (1987) 648-650, 1987.
Inspire Record 246624 DOI 10.17182/hepdata.20153

The real part of the isospin-even forward-scattering amplitude of pion-nucleon scattering has been determined at a pion energy of Tπ=55 MeV by measurement of the elastic scattering of positive and negative pions on protons within the Coulomb-nuclear interference region. The value confirms the prediction of the Karlsruhe-Helsinki phase-shift analysis for that energy. These phases have been used to determine the σ term of pion-nucleon scattering by means of dispersion relations, resulting in a value for σ which is in contradiction with chiral perturbation theory of QCD.

1 data table
Table 1

PI- P cross sections normalised to the Coulomb cross section taken from the Karlesruhe-Helsinki phase shift analysis (R. Koch, E. Pietarinen (NP A336(80)331).


Charged Particle Multiplicity and Angular Distributions in Proton Emulsion Interactions at 800-{GeV}

The BATON ROUGE-CRACOW-MOSCOW-TASHKENT collaboration Abduzhamilov, A. ; Barbier, L. ; Chernova, L.P. ; et al.
Phys.Rev.D 35 (1987) 3537-3540, 1987.
Inspire Record 254225 DOI 10.17182/hepdata.3930

The interaction of 800-GeV protons in nuclear emulsion has been investigated. The multiplicities and angular distributions of charged particles emitted by both the projectile and the target nucleus have been measured for 1718 inelastic events and are compared with the data obtained in proton-emulsion collisions at 67, 200, and 400 GeV. The target excitation is found to be independent of energy while the production of secondary particles continues to increase with incident proton energy.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Measurement of Anti-neutron Proton Total and Annihilation Cross-sections From 100-{MeV}/c to 500-{MeV}/c

The BROOKHAVEN-HOUSTON-PENNSYLVANIA STATE-RICE collaboration Armstrong, T. ; Chu, C. ; Clement, J. ; et al.
Phys.Rev.D 36 (1987) 659-673, 1987.
Inspire Record 253128 DOI 10.17182/hepdata.26943

Total and annihilation n¯p cross sections from 100 to 500 MeV/c are reported, the first such measurements with good statistics in this momentum range. These cross sections are well represented by A+B/p, where p is the incident antineutron momentum, and are in agreement with previous n¯p and p¯n measurements. A comparison of these cross sections with phenomenological potential model calculations is good overall. However, the microscopic quark model gives unsatisfactory predictions. The agreement between previous p¯p annihilation cross sections and n¯p cross sections above 300 MeV/c is excellent. The total n¯p cross section is lower than the total p¯p cross section in this momentum range. Both of these types of behavior are predicted by potential models. The anticipated availability of future p¯p data below 300 MeV/c should indicate whether these trends continue at lower momenta.

1 data table
Table 1

No description provided.


GENERAL FEATURES OF MULTIPARTICLE PRODUCTION IN INELASTIC anti-n p INTERACTIONS AT 6.1-GeV/c

The Dubna-Moscow-Bucharest-Sofiya collaboration Batyunya, B.V. ; Boguslavsky, I.V. ; Bruncko, D. ; et al.
Sov.J.Nucl.Phys. 46 (1987) 856, 1987.
Inspire Record 246883 DOI 10.17182/hepdata.38926

None

6 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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PRODUCTION OF LAMBDA HYPERONS AND K MESONS IN CUMULATIVE p C INTERACTIONS AT 10-GeV/c

Armutliisky, D. ; Bekmirzaev, R.N. ; Gasparian, A.P. ; et al.
Sov.J.Nucl.Phys. 47 (1988) 473, 1988.
Inspire Record 247873 DOI 10.17182/hepdata.38884

None

8 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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ANTI-P P TOTAL CROSS-SECTIONS BELOW 420-MEV/C

Bugg, D.V. ; Hall, J. ; Clough, A.S. ; et al.
Phys.Lett.B 194 (1987) 563-567, 1987.
Inspire Record 253124 DOI 10.17182/hepdata.30120

p̄p total cross sections have been measured from 220 to 413 MeV/ c in small (⩽ 10 MeV/ c ) steps of momentum with statistics of ± 0.5 %. There is no evidence for structure in the cross section, and a limit of 8 mb MeV/ c 2 is set with 90% confidence on the strength of any narrow resonance down to 250 MeV/ c .

2 data tables
Table 1

Data taken with long target.

Table 2

Data taken with short target.


Forward and Transverse Energy Distributions in Oxygen Induced Reactions at 60-agev and 200-agev

The WA80 collaboration Albrecht, R. ; Awes, T.C. ; Baktash, C. ; et al.
Phys.Lett.B 199 (1987) 297-303, 1987.
Inspire Record 254598 DOI 10.17182/hepdata.30059

Results are presented from reactions of 60 A GeV and 200 A GeV 16 O projectiles with C, Cu, Ag, and Au nuclei. Energy spectra measured at zero degrees and transverse energy distributions in the pseudorapidity range from 2.4 to 5.5 are shown. The average transverse energy per participant is found to be nearly independent of target mass. Estimates of nuclear stopping and of attained energy densities are made.

1 data table
Table 1

STOPPING POWER IS THE QUANTITY GIVEN IN THIS TABLE. IT IS DEFINED AS ( D(ET(EXP)/D(ETA) / D(ET(THEORY)/D(ETA) ) AND THE DENOMINATOR IS TAKEN TO BE 0.5*E(HADRON IN CM). ETA IS THE PSEUDO-RAPIDITY.


Strangeness Suppression and Inclusive $\phi$ and $K^*$0 Production in $K^+ P$ Interactions at 250-{GeV}/c

The EHS - NA22 collaboration Adamus, M. ; Agababyan, N.M. ; Ajinenko, I.V. ; et al.
Phys.Lett.B 198 (1987) 427-432, 1987.
Inspire Record 254217 DOI 10.17182/hepdata.30075

We present inclusive ¶ and K *0 (892) cross sections and Feynman x -spectra in K + p collisions at 250 GeV/ c . In the K + fragmentation region, x > 0.2, the ratio of ¶ to K *0 (892) is used to estimate the strangeness suppression factor λ , with the result γ =0.17 ± 0.02 (stat ± 0.01 (syst). We see no evidence for an energy dependence of λ in the CM energy range 7.8 ≤ s ≤21.7 GeV.

4 data tables
Table 1

RESULTS AT 32 AND 70 GEV INCLUDED FOR COMPARISON.

Table 2

RESULTS AT 32 AND 70 GEV INCLUDED FOR COMPARISON.

Table 3

RESULTS AT 32 AND 70 GEV INCLUDED FOR COMPARISON.

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