Kladnitskaya, E.N.
Photoproduction
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Estimate of the Delta(1232) component in the C-12 nucleus

Bystritsky, V.M. ; Glavanakov, I.V. ; Grabmayr, P. ; et al.
JETP Lett. 73 (2001) 453-456, 2001.
Inspire Record 563307 DOI 10.17182/hepdata.16707

The cross section for the 12C(γ, π+ p) reaction was measured in the range of the Δ(1232) isobar. The data were analyzed using the models taking into account the nucleon and isobaric degrees of freedom of the 12C nucleus. The conclusion is drawn that in the large-momentum transfer range the π+ p pairs are produced in the course of the direct knocking-out of Δ++ isobar from the nucleus. The probability of finding the Δ isobar in the ground-state 12C nucleus is estimated at 0.018±0.005 Δ isobars per nucleon.

1 data table
Table 1

The accuracy of the proton energy measurement = 4 MeV. The accuracy of the proton angles: DTHETA = 3 deg and DPHI = 2 deg. The background events < 3 pct for 450 MeV GAMMA energy (500 MeV of electron energy) and negligible for 400 MeV beam (420 MeV of electron energy). The estimation of the probability of finding DELTA in the ground state of C12 nucleus equals 0.018 +- 0.005 DELTA/nucleon.


Precise test of electroweak theory from a new measurement of parity nonconservation in atomic thallium

Vetter, P.A. ; Meekhof, D.M. ; Majumder, P.K. ; et al.
Phys.Rev.Lett. 74 (1995) 2658-2661, 1995.
Inspire Record 405007 DOI 10.17182/hepdata.19649

We report a new measurement of parity nonconserving (PNC) optical rotation near the 1.28 μm, 6P1/2→6P3/2 magnetic dipole transition in thallium. We find the ratio of the PNC E1 amplitude to the M1 amplitude to be R=(−14.68±0.17)×10−8, which within the present uncertainty of atomic theory yields the thallium weak charge Qw(T205l)=−114.2±3.8 and the electroweak parameter S=−2.2±3.0. Separate measurements on the F=1 and F=0 ground-state hyperfine components of the transition yield R1−R0=(0.15±0.20)×10−8, which limits the size of nuclear spin-dependent PNC in Tl.

1 data table
Table 1

Spin of the Tl nucleus is 1/2.


Measurement of total and partial photon proton cross-sections at 180-GeV center-of-mass energy

The ZEUS collaboration Derrick, M. ; Krakauer, D. ; Magill, S. ; et al.
Z.Phys.C 63 (1994) 391-408, 1994.
Inspire Record 372260 DOI 10.17182/hepdata.45055

Photon proton cross sections for elastic light vector meson production, σelνp, inelastic diffractive production, σndνp, non-diffractive production, σdνp, as well as the total cross section, σtotνp, have been measured at an average υp center of mass energy of 180 GeV with the ZEUS detector at HERA. The resulting values are σelνp = 18 ± 7 μb, σdνp = 33 ± 8 μb, σndνp = 91 ± 11 μb, and σtotνp 143 ± 17 μb, where the errors include statistical and systematic errors added in quadrature.

4 data tables
Table 1

No description provided.

Table 2

Errors contain both statistics and systematics.

Table 3

Cross section for the elastic (ie. gamma p --> VM p) cross section.. Errors contain both statistics and systematics.

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A Measurement of sigma(tot) (gamma p) at s**(1/2) = 210-GeV

The ZEUS collaboration Derrick, M. ; Krakauer, D. ; Magill, S. ; et al.
Phys.Lett.B 293 (1992) 465-477, 1992.
Inspire Record 339275 DOI 10.17182/hepdata.45171

The total photoproduction cross section is determined from a measurement of electroproduction with the ZEUS detector at HERA. The Q 2 values of the virtual photons are in the range 10 −7 < Q 2 <2×10 −2 GeV 2 . The γp total cross section in the γp centre of mass energy range 186–233 GeV is 154 ± 16 (stat.) ± 32 (syst.) μ b.

1 data table
Table 1

Scattered electron in range 10 to 16 GeV.


Study of charm photoproduction mechanisms

The NA14/2 collaboration Alvarez, M.P. ; Barate, R. ; Bloch, D. ; et al.
Z.Phys.C 60 (1993) 53-62, 1993.
Inspire Record 333271 DOI 10.17182/hepdata.14331

This paper presents results on charm photoproduction in the energy interval 40 to 160 GeV, obtained from the high-statistics charm samples of the NA 14/2 experiment at CERN. We measure the charm cross-section, the distributions inxF andp2T and various production ratios and charge asymmetries. The total non-diffractive open-charm cross-section per nucleon is measured to be\(\sigma _{(\gamma N \to c\bar cX)} \) at 〈Eγ〉 =100 GeV. We discuss the photoproduction of charm in terms of theoretical and phenomenological models. We compare the measuredp2T andxF distributions with first-order QCD calculations of photon-gluon fusion and obtain a value for the charm-quark mass ofmc=1.5+0.2−0.1GeV/c2.

10 data tables
Table 1

D0 cross section assuming branching ratio of D0 --> K- PI+ of 3.65 +- 0.21 PCT.

Table 2

D+(-) cross section assuming branching ratio of D+ --> K- PI+ PI+ of 8.0 +0.8,-0.7 PCT.

Table 3

Total non diffractive open charm production cross section allowing for contributions for other charmed particles (D/S and LAMBDA/C). Comparison of data with first order QCD leads to a predicted charm quark mass of 1.5 +0.2,-0.1 GeV.

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MEASUREMENT OF TOTAL PI0 MESON PHOTOPRODUCTION CROSS-SECTIONS ON LI-6 AND C-12 NUCLEI NEAR THE THRESHOLD. (IN RUSSIAN)

Glavanakov, I.V. ; Deinezhenko, A.L. ; Eponeshnikov, V.N. ; et al.
Yad.Fiz. 45 (1987) 3-7, 1987.
Inspire Record 250491 DOI 10.17182/hepdata.17419

None

1 data table
Table 1

No description provided.


Measurement of $J/\psi$ and $\psi^\prime$ Real Photoproduction on $^{6}$Li at a Mean Energy of 90-{GeV}

The NA14 collaboration Barate, R. ; Bareyre, P. ; Bloch, D. ; et al.
Z.Phys.C 33 (1987) 505, 1987.
Inspire Record 235579 DOI 10.17182/hepdata.15814

Inelastic and elasticJ/ψ (3097) photoproduction on Li6 are measured at a mean γ energy of 90 GeV in an open spectrometer. TheJ/ψ are identified by their decays intoμ+μ− ore+e−. A signal of ψ′(3685) intoμ+μ− andJ/ψπ+π− is also seen. The inelastic cross-section withZ=Eψ/Eγ<0.9 is compared in shape and magnitude with the colour singlet model of photon-gluon fusion.

2 data tables
Table 1

DIMUON TRIGGER, INELASTIC MEANS Z < 0.9.

Table 2

ELECTRON TRIGGER, INELASTIC MEANS Z < 0.9.


PARITY NONCONSERVING OPTICAL ROTATION IN ATOMIC LEAD

Emmons, T.P. ; Reeves, J.M. ; Fortson, E.N. ;
Phys.Rev.Lett. 51 (1983) 2089-2092, 1983.
Inspire Record 200168 DOI 10.17182/hepdata.20506

The search for parity nonconservation in heavy elements has been extended to the 1.28-μm P03→P13 magnetic dipole transition in atomic lead. The experimental result, R=Im(E1M1)=(−9.9±2.5)×10−8, agrees, within the present uncertainties in experiment and atomic theory, with the prediction, R=−13×10−8, derived from the Weinberg-Salam-Glashow theory of weak neutral-current interactions.

2 data tables
Table 1

No description provided.

Table 2

WE SUM BOTH STATISTICAL AND SYSTEMATIC ERRORS TO OBTAIN A WEIGHTED AVERAGE OF ALL DATA GROUPS. QUOTED ERROR INCLUDES STATISTICAL AND SYSTEMATIC CONTRIBUTIONS.


Measurement of Parity Nonconservation in Atomic Bismuth

Hollister, J.H. ; Apperson, G.R. ; Lewis, L.L. ; et al.
Phys.Rev.Lett. 46 (1981) 643-646, 1981.
Inspire Record 942914 DOI 10.17182/hepdata.20642

Parity-nonconserving optical rotation has been observed and measured on the 8757-ÅA magnetic-dipole absorption line in atomic bismuth vapor. The result, R≡Im(E1M1)=(−10.4±1.7)×10−8, is of the approximate size calculated with use of the Weinberg-Salam theory of the weak neutral-current interaction with sin2θW=0.23.

1 data table
Table 1

Axis error includes +- 0.0/0.0 contribution (?////NOT GIVEN).


PHOTOPRODUCTION OF eta MESONS AT 9.7-GeV

Nelson, C.A., Jr. ; Abramson, J. ; Andrews, D.E. ; et al.
Phys.Rev.D 19 (1979) 1931, 1979.
Inspire Record 132567 DOI 10.17182/hepdata.24307

Inclusive η photoproduction has been studied at 9.7 GeV, on hydrogen and deuterium targets. A simple, parameter-free ρ0-dominance model adequately fits the forward cross sections, but overestimates the cross section at large momentum transfer.

1 data table
Table 1

No description provided.