Efremenko, V.I.
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Measurement of the tensor analyzing power T(20) for d (polarized) + C-12 ---> p (0-degrees) + X in the region of internal momenta in the deuteron up to 1-GeV/c

Aono, T. ; Chernykh, E.V. ; Dzikowski, T. ; et al.
Phys.Rev.Lett. 74 (1995) 4997-5000, 1995.
Inspire Record 379428 DOI 10.17182/hepdata.19648

The tensor analyzing power T20 for the reaction d↑+12C→p(0°)+X has been measured in the region of proton internal momenta k in light-cone dynamics up to 1 GeV/ c. Measurements have been carried out at Dubna Synchrophasotron with polarized deuteron beam at deuteron momenta up to 9 GeV/ c. When k increases the experimental values of T20 have a tendency to approach the value ( −0.3) obtained by the calculation based on the reduced nuclear amplitude method in which the quark degrees of freedom are taken into account.

1 data table
Table 1

The momentum K, called momentum in light-cone dynamics, is expressed by thefollowing formula k**2=mt**2/(4*alpha*(1-alpha))-m**2,with mt**2=kt**2+m**2 wh ere kt is the proton transverse momentum.The light-cone variable alpha is the p art of the deuteron momentum carried by the proton in the infinite momentum frameand is expressed by the formula alpha=(Ep+Pp)/(Ed+Pd).


Photoproduction of J / psi mesons at HERA

The H1 collaboration Ahmed, T. ; Aid, S. ; Andreev, V. ; et al.
Phys.Lett.B 338 (1994) 507-518, 1994.
Inspire Record 376566 DOI 10.17182/hepdata.45103

We present a study of J ψ meson production in collisions of 26.7 GeV electrons with 820 GeV protons, performed with the H1-detector at the HERA collider at DESY. The J ψ mesons are detected via their leptonic decays both to electrons and muons. Requiring exactly two particles in the detector, a cross section of σ(ep → J ψ X) = (8.8±2.0±2.2) nb is determined for 30 GeV ≤ W γp ≤ 180 GeV and Q 2 ≲ 4 GeV 2 . Using the flux of quasi-real photons with Q 2 ≲ 4 GeV 2 , a total production cross section of σ ( γp → J / ψX ) = (56±13±14) nb is derived at an average W γp =90 GeV. The distribution of the squared momentum transfer t from the proton to the J ψ can be fitted using an exponential exp(− b ∥ t ∥) below a ∥ t ∥ of 0.75 GeV 2 yielding a slope parameter of b = (4.7±1.9) GeV −2 .

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

QED background subtracted.

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Nuclear structure function in carbon near x = 1

The BCDMS collaboration Benvenuti, A.C. ; Bollini, D. ; Camporesi, T. ; et al.
Z.Phys.C 63 (1994) 29-36, 1994.
Inspire Record 374300 DOI 10.17182/hepdata.48235

Data from deep inelastic scattering of 200 GeV muons on a carbon target with squared four-momentum transfer 52 GeV2≤Q2≤200 GeV2 were analysed in the region of the Bjorken variable close tox=1, which is the kinematic limit for scattering on a free nucleon. At this value ofx, the carbon structure function is found to beF2C≈1.2·10−4. Thex dependence of the structure function forx>0.8 is well described by an exponentialF2C∞exp(−sx) withs=16.5±0.6.

5 data tables
Table 1

No description provided.

Table 2

Multiplicative factors by which F2 has to be multiplied or divided to allow for a systematic uncertainty in detector resolution.

Table 3

Multiplicative factors by which F2 has to be multiplied or divided to allow for a systematic uncertainty in the beam energy.

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Inclusive charged particle cross-sections in photoproduction at HERA

The H1 collaboration Abt, I. ; Ahmed, T. ; Andreev, V. ; et al.
Phys.Lett.B 328 (1994) 176-186, 1994.
Inspire Record 372256 DOI 10.17182/hepdata.45105

Cross sections are presented for the inclusive production of charged particles measured in electron-proton collisions at low Q 2 with the H1 detector at HERA. The transverse momentum distribution extends up to 8 GeV/ c . Its shape is found to be harder than that observed in p p collisions at comparable centre-of-mass energies √S γp ≈ √S p p ≈ 200 GeV , and also harder than in γp collisions at lower energies √ S γp ≈ 18 GeV. Results from quantum chromodynamics (QCD) calculations agree with the measured transverse momentum and pseudorapidity cross sections.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


rivet Analysis
Energy flow and charged particle spectrum in deep inelastic scattering at HERA

The H1 collaboration Abt, I. ; Ahmed, T. ; Andreev, V. ; et al.
Z.Phys.C 63 (1994) 377-390, 1994.
Inspire Record 372350 DOI 10.17182/hepdata.45101

Global properties of the hadronic final state in deep inelastic scattering events at HERA are investigated. The data are corrected for detector effects and are compared directly with QCD phenomenology. Energy flows in both the laboratory frame and the hadronic centre of mass system and energy-energy correlations in the laboratory frame are presented. Comparing various QCD models, the colour dipole model provides the only satisfactory description of the data. In the hadronic centre of mass system the momentum components of charged particles longitudinal and transverse to the virtual boson direction are measured and compared with lower energy lepton-nucleon scattering data as well as withe+e− dat from LEP.

4 data tables
Table 1

Overall systematic error of 6 pct not included.

Table 2

Corrected transverse energy-energy correlation TEEC as a function of omega (see text of paper for definition of omega - which effectively defines the distance between hadrons in the pseudorapidity and azimuthal angle). Overall systematic error of 12 pct is not included.

Table 3

Charged particle spectra as a function of the Feynman x variable for different ranges of the hadronic mass W.

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The Search for heavy pentaquark exotic baryons with hidden strangeness in the p + N ---> (p Phi) + N and p + N ---> (Lambda (1520) K+) + N reactions at E(p) = 70-GeV

The SPHINX collaboration Dorofeev, V.A. ; Golovkin, S.V. ; Kozhevnikov, A.P. ; et al.
Phys.Atom.Nucl. 57 (1994) 227-237, 1994.
Inspire Record 385732 DOI 10.17182/hepdata.40688

None

2 data tables
Table 1

No description provided.

Table 2

The upper limits for production of EXOTIC-NUCLEON with narrow width (<50 MeV). Linear A-dependence of the cross section is assumed.


Annihilation cross-sections of anti-neutrons on C, Al, Cu, Sn and Pb at low momenta (180-MeV/c - 280-MeV/c) with the OBELIX spectrometer

The OBELIX collaboration Ableev, V.G. ; Adamo, A. ; Agnello, M. ; et al.
Nuovo Cim.A 107 (1994) 943-953, 1994.
Inspire Record 384438 DOI 10.17182/hepdata.37841

Annihilation cross-sections σann for antineutrons on some nuclei (C, Al, Cu, Sn and Pb) at three antineutron momenta (180, 240 and 280 MeV/c) were measured at LEAR (CERN) with the OBELIX spectrometer. A behaviour σann=σ0Aν has been found withν≈2/3. The data are discussed following some models for antineutron-nucleus interaction.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Phi and omega meson production in anti-n p annihilation and the OZI rule

The OBELIX collaboration Ableev, V.G. ; Agnello, M. ; Balestra, F. ; et al.
Phys.Lett.B 334 (1994) 237-243, 1994.
Inspire Record 383126 DOI 10.17182/hepdata.28740

The φπ + /ωπ + ratio from n¯p annihilations on a liquid hydrogen target, for n¯ momenta between 64 and 297 MeV/ c , was measured using the OBELIX spectrometer at LEAR. The ratio R(ϕπ/ωπ)=σ(n¯p→ϕπ+)/σ(n¯p→ωπ+) turned out 0.110±0.015 stat ±0.006 syst . Implications of this result on the OZI rule are discussed.

1 data table
Table 1

Assumes branching ratios of (49.1 +- 0.8)% for phi --> K+ K- and (88.8 +- 0.6)% for omega --> pi+ pi- pi0.


Search for N (phi) (1960) baryon

The SPHINX collaboration Balats, M.Ya. ; Belyaev, I.M. ; Dorofeev, V.A. ; et al.
Z.Phys.C 61 (1994) 399-405, 1994.
Inspire Record 376444 DOI 10.17182/hepdata.14371

In the experiments at the SPHINX facility in the 70 GeV proton beam of the IHEP accelerator the diffractive production reactionsp+N→[Σ(1385)0K+] +N andp+N→[Σ(1385)0K+]+N+ (neutral particles) were studied. In the effective mass spectra of the [Σ(1385)0K+] system in these processes there were no signals from the anomalously narrow baryon stateNϕ (1960) which had been observed earlier in the measurement at the BIS-2 setup.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Polarization of Lambda hyperons in n C and n Pb interactions at initial momenta of 4-GeV/c to 10-GeV/c

Vishnevsky, M.E. ; Vlasova, M.O. ; Galanina, N.D. ; et al.
Phys.Atom.Nucl. 57 (1994) 985-990, 1994.
Inspire Record 383446 DOI 10.17182/hepdata.17186

None

2 data tables
Table 1

No description provided.

Table 2

No description provided.