Bigi, A.
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CHARACTERISTICS OF NEUTRAL CURRENT INTERACTIONS INDUCED BY NEUTRINOS

Marriner, J. ; Barbaro-Galtieri, A. ; Bosetti, P. ; et al.
Phys.Rev.D 27 (1983) 2569-2579, 1983.
Inspire Record 195608 DOI 10.17182/hepdata.23834

The ratio of neutral-current to charged-current interactions is measured to be 0.30±0.03 for isoscalar targets, in good agreement with the results of previous experiments. Two independent methods are employed for isolating neutral-current events, one based on hadronic interactions, and the other on the momentum transverse to the hadron shower. The ratio of neutral-current interactions on neutrons to those on protons is measured to be 1.08±0.19.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


STUDY OF A2 PRODUCTION IN THE REACTION PI- P ---> K0 K- P AT 50-GEV/C, 100-GEV/C, AND 175-GEV/C

Bromberg, C. ; Dickey, J.o. ; Fox, G. ; et al.
Phys.Rev.D 27 (1983) 1-11, 1983.
Inspire Record 191493 DOI 10.17182/hepdata.23901

The reaction π−p→K0K−p has been measured from 50 to 175 GeV/c. The production characteristics of the A2 have been analyzed. We find spin and t dependence similar to lower energies, but the cross section falls rapidly with energy. In a Regge description of π−p→A2−p our data imply a rather small Pomeron-exchange component.

6 data tables
Table 1

No description provided.

Table 2

RAW CROSS SECTION WITHIN MASS CUTS.

Table 3

No description provided.

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The Reactions $pp \to pp$ $\pi^+ \pi^-, K^+ p \to K^+ p$ $\pi^+ \pi^-$, $\pi^+ p \to \pi^+ p$ $\pi^+ \pi^-$ and $\pi^- p \to \pi^+ \pi^-$ at 147 GeV/c

Brick, D.H. ; Rudnicka, H. ; Shapiro, A.M. ; et al.
Z.Phys.C 19 (1983) 1-9, 1983.
Inspire Record 194363 DOI 10.17182/hepdata.16321

We have studied the reactionspp→ppπ+π-,K+p→K+pπ+π−π, π+p→ π+,pπ+π− and π−p →π+π− at 147 GeV/c using the 30-inch Fermilab hybrid system. All four reactions were detected with the same apparatus and analyzed in the same way. The energy dependence of the channel cross section was found to beAp−0.6+B for thepp reaction andAp−1+B for the other three. About 90% of the cross section at 147 GeV/c can be accounted for by either beam or target diffraction. Some of the remaining cross section may come from double Pomeron exchange reactions which we tried to isolate. We have tested the hypothesis of a factorizable Pomeron and our data indicates a violation of this hypothesis. We show that the 3π mass enhancement in the mass region 1.2–1.4 GeV is diffractively produced in the π± beam reactions. Fourprong, four-constraint and six-prong, four-constraint cross sections are reported.

6 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

CROSS SECTIONS FOR DIFFRACTION DISSOCIATION OF BEAM. FEYNMAN X OF OUTGOING PROTON <-0.96.

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High-Energy Quasielastic $\nu_{\mu} n \to \mu^- p$ Scattering in Deuterium

Kitagaki, T. ; Tanaka, S. ; Yuta, H. ; et al.
Phys.Rev.D 28 (1983) 436-442, 1983.
Inspire Record 195139 DOI 10.17182/hepdata.23772

We have studied the quasielastic reaction νμn→μ−p in an exposure of the Fermilab deuterium-filled 15-foot bubble chamber to a high-energy wide-band neutrino beam. From an analysis of the Q2 distribution based on the standard V−A theory, the axial-vector mass in a dipole parametrization of the axial-vector form factor is determined to be MA=1.05−0.16+0.12 GeV, consistent with the values previously reported from low-energy experiments.

1 data table
Table 1

Measured Quasi-Elastic total cross section.


Neutrino and anti-neutrinos Charged Current Inclusive Scattering in Iron in the Energy Range 20-GeV < Neutrino Energy < 300-GeV

Abramowicz, H. ; de Groot, J.G.H. ; Knobloch, J. ; et al.
Z.Phys.C 17 (1983) 283, 1983.
Inspire Record 182549 DOI 10.17182/hepdata.2213

Inclusive charged-current interactions of high-energy neutrinos and antineutrinos have been studied with high statistics in a counter experiment at the CERN Super Proton Synchrotron. The energy dependence of the total cross-sections, the longitudinal structure function, and the nucleon structure functionsF2,xF3, and\(\bar q^{\bar v} \) are determined from these data. The analysis of theQ2-dependence of the structure functions is used to test quantum chromodynamics, to determine the scale parameter Λ and the gluon distribution in the nucleon.

50 data tables
Table 1

ABSOLUTE FLUXES HAVE NOT BEEN MEASURED. NORMALISED TO OLD RESULTS.

Table 2

STUCTURE FUNCTIONS ARE EVALUATED ASSUMING R=SIG(L)/SIG(T)=0.1 AND M(W) IS INFINITE. NO CORRECTION FOR FERMI MOTION APPLIED. ERRORS ARE STATISTICAL AND SYSTEMATIC POINT-TO-POINT ERRORS. IN ADDITION OVER-ALL SCALE ERROR OF 6 PCT. FOR F2 , 8 PCT. FOR XF3.

Table 3

STUCTURE FUNCTIONS ARE EVALUATED ASSUMING R=SIG(L)/SIG(T)=0.1 AND M(W) IS INFINITE. NO CORRECTION FOR FERMI MOTION APPLIED. ERRORS ARE STATISTICAL AND SYSTEMATIC POINT-TO-POINT ERRORS. IN ADDITION OVER-ALL SCALE ERROR OF 6 PCT. FOR F2 , 8 PCT. FOR XF3.

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Charm $D$ Meson Production in 360-{GeV} $\pi^- p$ Interactions: Evidence for Leading Quarks

The LEBC-EHS collaboration Aguilar-Benitez, M. ; Allison, W.W.M. ; Bagnaia, P. ; et al.
Phys.Lett.B 123 (1983) 98-102, 1983.
Inspire Record 182456 DOI 10.17182/hepdata.30715

Charm D-meson production in 360 GeV π − p interactions has been studied using the high-resolution hydrogen bubble chamber LEBC and the European Hybrid Spectrometer. The data show evidence for leading quark effects both in the number of D-meson types and in the Feynman x distributions. The production cross section is of the form d 2 δ d x d p T 2 ∞(1-x) n exp (-ap T 2 ) with n = 2.8±0.8 and a = 1.1±0.3 (GeV/ c ) −2 . The x distribution is, however, compatible with the presence of both central ( n = 6) and leading (n = 1) D / D production. The fraction of D-messons in the leading component is estimated to be ≈30%. The rapidity gap between members of reconstructed charm pairs is small compared to the available rapidity range. The inclusive cross section for single D-messons in the forward direction is: δ(D/ D )=(40 8 +15 )μ b ( for x>0) .

1 data table
Table 1

No description provided.


Charm $D$ Meson Production in 360-{GeV}/$c p p$ Interactions: Comparison With $\pi^- p$ at the Same Energy

The LEBC-EHS collaboration Aguilar-Benitez, M. ; Allison, W.W.M. ; Bagnaia, P. ; et al.
Phys.Lett.B 123 (1983) 103-107, 1983.
Inspire Record 182457 DOI 10.17182/hepdata.30746

Charm D-meson production in 360 GeV pp interactions has been studied using the high-resolution hydrogen bubble chamber LEBC and the European Hybrid Spectrometer. D-mesons are produced with a differential cross section of the form d 2 σ d x d p T 2 δ(1-x) n exp (-ap T 2 ) , with n =1.8± 0.8 and a =1.1±0.03 GeV/ c −2 for the Feynman x and Transverse momentum p T behaviour. The inclusive partle prticle crossssection for D and D̄;measured to be: σ(D/ D ̄ ) = (56 −12 25 μ b (for all x ). The Λ c D ̄ cross section can be estimated to be ≈20 μ b. No strong correlation is observed between DD̄ pairs. The results are compared with results from a study of D-meaon production in 360 GeV/ c π − p interactions also using LEBC-EHS.

1 data table
Table 1

No description provided.


Investigation of Two Photon Final States in $e^+ e^-$ Annihilation at $\sqrt{s}=34$.2-{GeV}

The CELLO collaboration Behrend, H.J. ; Chen, C. ; Fenner, H. ; et al.
Phys.Lett.B 123 (1983) 127-132, 1983.
Inspire Record 182585 DOI 10.17182/hepdata.30780

Two photon final states in e + e − annihilation have been analyzed at CM energies around 34 GeV. Good agreement with QED is observed. Lower limits for the QED cutoff parameters of Λ + > 59 GeV and Λ - > 44 GeV are determined. A search for two photons with missing energy yields an upper limit for the production of neutral particles which decay into a photon and a non-interacting particle. Constraints on the mass and the coupling strength of supersymmetric photinos are discussed.

2 data tables
Table 1

Cross section for ABS(cos(theta)) <0.85.

Table 2

No description provided.


Inclusive $\phi$ Meson Production in $K^-$, $\bar{p}$ and $p$ Be Interactions at 100-{GeV}/$c$

The ACCMOR collaboration Daum, C. ; Hertzberger, L.O. ; Hoogland, W. ; et al.
Z.Phys.C 18 (1983) 1, 1983.
Inspire Record 183362 DOI 10.17182/hepdata.16360

Inclusive ϕ-meson production has been measured for 100 GeV/cK−,\(\bar p\) andp incident on a Be target. Differential cross sectionsdσ/dxF anddσ/dp⊥2 are presented in the interval 0.075<xF<0.225 and 0<p⊥<1 GeV/c respectively. The shape of thedσ/dxF distributions agrees with predictions from a quark fusion model. Comparison with cross sections measured on a hydrogen target in the samexF andp⊥ range suggest a linearA-dependence fromA=1 toA=9.

1 data table
Table 1

No description provided.


rivet Analysis
Search for Top Quark and a Test of Models Without Top Quark at the Highest {PETRA} Energies

Adeva, B. ; Barber, D.P. ; Becker, U. ; et al.
Phys.Rev.Lett. 50 (1983) 799, 1983.
Inspire Record 182337 DOI 10.17182/hepdata.20549

With a PETRA energy scan in ≤30-MeV steps, the continuum production of open top quark up to 38.54 GeV is excluded. Over regions of energy scan from 29.90 to 38.63 GeV limits are set on the product of hadronic branching ratio and electronic width BhΓee for toponium to be less than 2.0 keV at the 95% confidence level. By a search for flavor-changing neutral currents in b decay, models without a top quark are excluded.

4 data tables
Table 1

MEASUREMENT OF R IN ENERGY SCAN FROM SQRT(S) = 29.9 TO 3.146 AND 33.0 TO 36.72.

Table 2

MEASUREMENT OF R IN THE RANGE SQRT(S) 37 TO 38.63 GEV.

Table 3

THRUST DISTRIBUTION FOR EVENTS IN THE RANGE SQRT(S) 37.94 TO 38.63 AND 38.54 TO 38.63.

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