Fries, D.C.
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The Spin Correlation Parameter and Analyzing Power in $n p$ Elastic Scattering at Intermediate-energies

Abegg, R. ; Ahmad, M. ; Bandyopadhyay, D. ; et al.
Phys.Rev.C 40 (1989) 2684-2696, 1989.
Inspire Record 281880 DOI 10.17182/hepdata.26220

In order to improve existing I=0 phase shift solutions, the spin correlation parameter ANN and the analyzing powers A0N and AN0 have been measured in n-p elastic scattering over an angular range of 50°–150° (c.m.) at three neutron energies (220, 325, and 425 MeV) to an absolute accuracy of ±0.03. The data have a profound effect on various phase parameters, particularly the P11, D23, and ε1 phase parameters which in some cases change by almost a degree. With the exception of the highest energy, the data support the predictions of the latest version of the Bonn potential. Also, the analyzing power data (A0N and AN0) measured at 477 MeV in a different experiment over a limited angular range [60°–80° (c.m.)] are reported here.

10 data tables
Table 1

The beam analysing power at incident kinetic energy 220 MeV. Additional systematic uncertainty of +- 0.015 and a scalar error of 3.5 PCT.

Table 2

The beam analysing power at incident kinetic energy 325 MeV. Additional systematic uncertainty of +- 0.018 and a scalar error of 3.1 PCT.

Table 3

The beam analysing power at incident kinetic energy 425 MeV. Additional systematic uncertainty of +- 0.022 and a scalar error of 3.3 PCT.

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The $K^0_S K^0_S$ Final State in $\gamma \gamma$ Interactions

The CELLO collaboration Behrend, H.J. ; Criegee, L. ; Dainton, J.B. ; et al.
Z.Phys.C 43 (1989) 91, 1989.
Inspire Record 267756 DOI 10.17182/hepdata.15432

In the reaction γγ→KS0KS0 resonance production of thef2− is observed. For the radiative with\(\Gamma _{\gamma \gamma } .B(f'_2\to K\bar K) = 0.11_{ - 0.02}^{ + 0.03}\pm 0.02keV\) is found. The small number of events in thef2,a2 mass region is consistent with the assumption of destructivef2−a2 interference. From the mass distribution we determine the relative phases between the tensor mesons. Upper limits on the radiative widths of the glueball candidatesf2(1720) andX (2220) are derived.

3 data tables
Table 1

Only bins containing events are included, all others are zero.. Untagged plus single events.. Data read from graph.

Table 2

Only bins containing events are included, all others are zero.. Untagged events.. Data read from graph.

Table 3

Corrected for the angular distribution, which is assumed to be sin(theta)**4. Additional systematic error decreasing from 20% in the lowest mass bins to 15% for W > 1.5 GeV.. Data read from graph.


$K^0(s$) $K \pi$ Production in Tagged and Untagged $\gamma \gamma$ Interactions

The CELLO collaboration Behrend, H.J. ; Criegee, L. ; Dainton, J.B. ; et al.
Z.Phys.C 42 (1989) 367, 1989.
Inspire Record 266414 DOI 10.17182/hepdata.15529

We have searched for resonance production in the reaction γγ→Ks0Kπ. No signal was found for theηc and an upper limit for the radiative with\(\Gamma _{\gamma \gamma }^{\eta _c } \) keV (95% c.l.) is obtained. For the glueball candidate η(1440) (previouslyi) the upper limit\(\Gamma _{\gamma \gamma }^{\eta (1440)} B(\eta (1440) \to K\bar K\pi )< 1.2keV(95\% c.l.)\) is derived. In the tagged data sample resonance formation of a spin 1 state at 1420 MeV is observed, which is absent in the untagged data. The mass and width of this state are consistent with those of thef1(1420); an analysis of decay angular distributions favours positive parity.

1 data table
Table 1

Data read from graph.. Additional overall systematic error decreasing from 25% in the lowest mass bins to 15% for M > 2.0 GeV.


Charge Symmetry Breaking in $n p$ Elastic Scattering at 477-{MeV}

Abegg, R. ; Bandyopadhyay, D. ; Birchall, J. ; et al.
Phys.Rev.D 39 (1989) 2464, 1989.
Inspire Record 267187 DOI 10.17182/hepdata.23224

The effect of isospin-violating, charge-symmetry-breaking (CSB) terms in the np interaction has been observed at TRIUMF by measuring the difference in the zero-crossing angles of the neutron and proton analyzing powers, An and Ap, at a neutron energy of 477 MeV. The scattering asymmetries were measured with a neutron beam incident on a polarizable proton target. To reduce systematic errors, interleaved measurements of An and Ap were made using the same beam and target (apart from their respective polarization states). Neutrons and protons were detected in coincidence in the center-of-mass angle range from 59°–80°. The difference in zero-crossing angles was 0.340°±0.162° (±0.058°), which yields ΔA≡An-Ap=0.0047±0.0022 (±0.0008) using dA/dθc.m.=−0.01382 deg−1. The second errors represent systematic effects. This result is in good agreement with recent theoretical calculations which include CSB effects due to the np mass difference in π, ρ, and 2π exchange, electromagnetic coupling of the neutron anomalous magnetic moment to the proton current, ρ-ω-meson mixing, and short- and medium-range effects of the up- and down-quark mass difference.

1 data table
Table 1

No description provided.


Measurement of the Spin Rotation Parameter, Beta, in the Reaction $\pi^+ p \to K^+ \Sigma^+$ at 1.60-{GeV}/$c$ and 1.88-{GeV}/$c$

Candlin, D.J. ; Lowe, D.C. ; Peach, K.J. ; et al.
Nucl.Phys.B 311 (1989) 613-629, 1989.
Inspire Record 263837 DOI 10.17182/hepdata.33220

Values of the spin-rotation parameter, β, are measured in the reaction π + p → K + Σ + at incident pion momenta of 1.69 and 1.88 GeV/ c .

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Measurement of Neutrino - Proton and anti-neutrino - Proton Elastic Scattering

Ahrens, L.A. ; Aronson, S.H. ; Connolly, P.L. ; et al.
Phys.Rev.D 35 (1987) 785, 1987.
Inspire Record 18763 DOI 10.17182/hepdata.23350

Measurements of the semileptonic weak-neutral-current reactions νμp→νμp and ν¯μp→ν¯μp are presented. The experiment was performed using a 170-metric-ton high-resolution target detector in the BNL wide-band neutrino beam. High-statistics samples yield the absolute differential cross sections dσ(νμp)/dQ2 and dσ(ν¯μp)/dQ2. A measurement of the axial-vector form factor GA(Q2) is also presented. The results are in good agreement with the standard model SU(2)×U(1). The weak-neutral-current parameter sin2thetaW is determined to be sin2θW=0.220±0.016(stat)−0.031+0.023(syst).

1 data table
Table 1

Errors contain both statistics and systematics, except for additional overall normalisation error given above. Neutrino energy is 0 to 5 GeV with peak at 0.8 Gev.


Precise Determination of Sin**2-$\theta^-$w From Measurements of the Differential Cross-sections for $\nu_\mu p \to \nu_\mu p$ and $\bar{\nu}_\mu p \to \bar{\nu}_\mu p$

Ahrens, L.A. ; Aronson, S.H. ; Connolly, P.L. ; et al.
Phys.Rev.Lett. 56 (1986) 1107, 1986.
Inspire Record 218044 DOI 10.17182/hepdata.20261

This paper describes measurements of the semileptonic weak-neutral-current reactions νpμ→νpμ and ν¯pμ→ν¯pμ which yield the absolute differential cross sections dσ(νpμ)dQ2 and dσ(ν¯pμ)dQ2. The weak-neutral-current parameter, sin2θW, is determined to be sin2θW=0.220±0.016(stat.)(syst.)−0.031+0.023.

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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MEASUREMENT OF THE REACTION gamma p ---> p anti-p p AT PHOTON ENERGIES 4.7-GeV <= E (gamma) <= 6.6-GeV

Bodenkamp, J. ; Fries, D.C. ; Markou, A. ; et al.
Nucl.Phys.B 255 (1985) 717-746, 1985.
Inspire Record 15090 DOI 10.17182/hepdata.33786

An experimental investigation of the reaction γ p → p p p at photon energies 4.7 ⩽ E γ ⩽ 6.6 GeV is described. The main results are the measurement of the cross section as a function of energy, a discussion of the main dynamical features of the reaction and the observation of a narrow p p mass state at 2.024 ± 0.005 GeV with a width of 29 ± 13 MeV.

3 data tables
Table 1

OBSERVATION OF THIS CHANNEL AS A CONSISTENCY CHECK ON THE NORMALIZATION.

Table 2

No description provided.

Table 3

MEASUREMENTS OF CROSS SECTIONS OF MASS SIGNALS AT 1.94 AND 2.024 GEV, EVALUATE BY FITTING TWO BREIT WIGNERS AND CONSTANT BACKGROUND TO (AP P) MASS SPECTRUM. ERRORS ARE STATISTICAL ONLY.


Search for a Threshold Enhancement in the $\gamma (p) \to$ Charmed Baryon + Charmed Meson Cross-section

The SLAC Hybrid Facility Photon collaboration Abe, K. ; Bacon, T.C. ; Bingham, H.H. ; et al.
Phys.Rev.D 30 (1984) 694, 1984.
Inspire Record 200010 DOI 10.17182/hepdata.23592

Results of a search for a predicted enhancement of several microbarns in the charm-photoproduction cross section just above threshold are reported. No charm decays were detected, from which an upper limit to the charm cross section of 94 nb (90% C.L.) at Eγ≃10 GeV was obtained. Upper limits in the range 270 to 450 nb were also obtained for the peak cross sections for threshold enhancements in γp→D−Σc++ and similar channels.

2 data tables
Table 1

UPPER LIMIT TO AVERAGE CHARM CROSS SECTION.

Table 2

UPPER LIMITS TO INDIVIDUAL CHANNELS.


A MEASUREMENT OF pi+ p BACKWARD ELASTIC DIFFERENTIAL CROSS-SECTIONS FROM 1.282-GeV/c TO 2.472-GeV/c

Candlin, D.J. ; Lowe, D.C. ; Peach, K.J. ; et al.
Nucl.Phys.B 244 (1984) 23-56, 1984.
Inspire Record 201771 DOI 10.17182/hepdata.7101

New high-statistics measurements of π + p elastic scattering differential cross sections are presented at 30 momentum points between 1.282 and 2.472 GeV/ c , covering most of the angular distribution outside the forward diffractive peak. These data show significant disagreements at some momenta with previous high-statistics experiments and with current partial wave analyses.

30 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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