Allison, J.
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Search for Charmed Mesons Produced in Hadronic Interactions

Ginther, G. ; Edelstein, R.M. ; Forsyth, C.P. ; et al.
Phys.Rev.D 35 (1987) 1541-1552, 1987.
Inspire Record 252546 DOI 10.17182/hepdata.23386

The hadronic production of charmed states was studied in a two-arm spectrometer using a 205-GeV/c negative-pion beam incident upon a beryllium target. One arm, filled with dense absorber, triggered the detectors upon the passage of a muon with a moderate transverse momentum and a total momentum of at least 4 GeV/c. The other arm was an open-geometry magnetic spectrometer which had both neutral- and charged-particle identification capabilities. The apparatus, the data, and an invariant-mass-plot search for evidence of charmed-meson production through several charged-particle decay modes are described. The Kπ, Kππ, and Kπππ mass plots fail to reveal significant D-meson signals. Based upon the Kπ mass plots, the 95%-confidence upper limit on the DD¯ production cross section is found to be less than 51 μb per nucleon for the production models tested. A search for evidence of charged-D* production yields 30±16 combinations above background in association with the expected trigger muon charge. Interpreted as a D* signal, this excess corresponds to a model-dependent inclusive DD¯ production cross section of 34±18−9+14 μb per nucleon. Model-dependent upper limits on the ratio of the F to D cross sections are also presented.

4 data tables
Table 1

Uncorrelated model for charmed mesons production.

Table 2

'Correlated' model for pair of charmed mesons production.

Table 3

Uncorrelated model for D/S+- mesons production.

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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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NEUTRAL STRANGE PARTICLE PRODUCTION IN HIGH TRANSVERSE MOMENTUM pi- NUCLEUS INTERACTIONS AT approximately 40-GeV/c

The RISK collaboration Barwolff, H. ; Dreher, C. ; Friebel, W. ; et al.
Z.Phys.C 37 (1988) 337, 1988.
Inspire Record 251304 DOI 10.17182/hepdata.15678

Measurements ofKs0, Λ and\(\bar \Lambda \) production in π− nucleus (C, Cu, Pb) interactions are presented. The experiment was carried out with the streamer chamber spectrometer RISK using a π− beam of ∼40 GeV/c and a trigger requiring a secondary charged particle with transverse momentum above 1.1 GeV/c. Production cross sections, relative production rates and distributions of Feynmanx and transverse momentum squared as well as correlations between theV0 and the trigger particle are presented. The results are compared and found to be in agreement withKs0, Λ and\(\bar \Lambda \) data from untriggered π−p and π−C interactions, except for the relative production rate of antilambdas which is about to times larger in high-pt collisions. Our results can be well interpreted within the dual topological unitarization model.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


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).


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.


Measurement of inclusive cross sections for production of cumulative protons in pi-, K-, and anti-p interactions in Be at 40-GeV/c.

Antipov, Yu.M. ; Batarin, V.A. ; Bezzubov, V.A. ; et al.
Sov.J.Nucl.Phys. 48 (1988) 297-300, 1988.
Inspire Record 254775 DOI 10.17182/hepdata.40801

None

1 data table
Table 1

No description provided.


TOTAL CROSS-SECTION MEASUREMENT OF THE REACTION AL-27 (C-12, X) NA-24 AT 3.65-GEV/NUCLEON. (IN RUSSIAN)

Damdinsuren, Ts. ; Duka-Zoiomi, A. ; Kliman, J. ; et al.
DUBNA JINR - 87-932 (87,REC.MAR.88) 4p, 1987.
Inspire Record 255685 DOI 10.17182/hepdata.38909

None

2 data tables
Table 1

No description provided.

Table 2

No description provided.


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.


Polarization of Sigma0 hyperons in inclusive production from 28.5-GeV/c protons on beryllium

Dukes, E.C. ; Overseth, O.E. ; Bunce, G.M. ; et al.
Phys.Lett.B 193 (1987) 135-139, 1987.
Inspire Record 249257 DOI 10.17182/hepdata.30125

The polarization of Σ 0 hyperons produced in an inclusive reactons hasbeen measured for the first time. From a sample of 11 000 events produced by 28.5 GeV/ c ptorons in the reaction p+ Be → Σ 0 +X, the Σ 0 polarization has a value of +0.28±0.13 at p t =1.01 GeV/ c and x f =0.60. The polarization of 53 000 Λ hyperons produced from 28.5 Gev/ c protons inthe reaction p+Be→ Λ +X has been measured in the kinematic range 0.64< p t <1.14 GeV/ c and 0.42< x f <0.62. The average Λ polarization is found to be −0.188±0.024, consistent with previous results.

2 data tables
Table 1

No description provided.

Table 2

No description provided.