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Measurement of the Magnetic Moments of $\Sigma^+$ and $\bar{\Sigma}$ Hyperons

The E761 collaboration Morelos Pineda, Antonio ; Albuquerque, I.F. ; Bondar, N.F. ; et al.

Phys.Rev.Lett. 71 (1993) 3417-3420, 1993.

Inspire Record 359369 DOI 10.17182/hepdata.19719

We have measured the magnetic moments of the Σ+ and Σ¯ − hyperons produced by 800-GeV protons incident on a Cu target. We determine the Σ+ magnetic moment to be (2.4613±0.0034±0.0040)μN where the uncertainties are statistical and systematic, respectively. In this first measurement we determine the magnetic moment of the Σ¯ − to be -(2.428±0.036±0.007)μN. The magnetic moments of the Σ+ and Σ¯ − are consistent with each other in magnitude but opposite in sign as required by CPT invariance.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

Observation of D(s)** (2536) meson production by neutrinos in BEBC

The Big Bubble Chamber Neutrino collaboration Asratyan, A.E. ; Aderholz, M. ; Ammosov, V.V. ; et al.

Z.Phys.C 61 (1994) 563-566, 1994.

Inspire Record 363214 DOI 10.17182/hepdata.14264

Neutrino interactions in BEBC produce theDS** (2536) charmed strange meson. The mass of this state is 2534.2±1.2 MeV. The production rate is 0.011±0.005 per neutrino charged current interaction at a mean neutrino energy of 61 GeV. An earlier claim for another$c\bar s$ bound state near 2565 MeV, produced in neutrino interactions, is not supported.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

rivet Analysis
The Measurement of R in e+ e- annihilation at center-of-mass energies between 7.2-GeV and 10.34-GeV

Blinov, A.E. ; Blinov, V.E. ; Bondar, A.E. ; et al.

Z.Phys.C 70 (1996) 31-38, 1996.

Inspire Record 364141 DOI 10.17182/hepdata.14321

The total cross section of the processe+e− →hadrons has been measured in the center-of-mass energy range between 7.25 and 10.34 GeV using the MD-1 detector at the VEPP-4 collider. The ratioR=σ(e+e− →hadrons)/σ(e+e− →μ+μ−) was found to be constant in this energy range with the average value of 3.58±0.02±0.14.

2 data tables

Table 1

Statistical errors only.

Table 2

Mean value of R in the range 7.25 to 10.34 GeV.

A Precise measurement of the weak mixing angle in neutrino nucleon scattering

The CCFR collaboration Arroyo, C. ; King, B.J. ; Bachmann, K.T. ; et al.

Phys.Rev.Lett. 72 (1994) 3452-3455, 1994.

Inspire Record 360411 DOI 10.17182/hepdata.37276

We report a precise measurement of the weak mixing angle from the ratio of neutral current to charged current inclusive cross-sections in deep-inelastic neutrino-nucleon scattering. The data were gathered at the CCFR neutrino detector in the Fermilab quadrupole-triplet neutrino beam, with neutrino energies up to 600 GeV. Using the on-shell definition, ${\rm sin ~2\theta_W} \equiv 1 - \frac{{\rm M_W} ~2}{{\rm M_Z} ~2}$, we obtain ${\rm sin ~2\theta_W} = 0.2218 \pm 0.0025 ({\rm stat.}) \pm 0.0036 ({\rm exp.\: syst.}) \pm 0.0040 ({\rm model})$.

1 data table

Table 1

Using the on-shell definition, sin2tw = 1-Mw**2/Mz**2.. Analysis contained 475 627 events after all cuts.. The first systematic error is experimental, the second is theoretical.

Investigation of diffraction processes p + N ---> (p p anti-p) + N and p + N ---> (p p anti-p pi0) + N at E(p) = 70-Gev

The SPHINX collaboration Vavilov, D.V. ; Viktorov, V.A. ; Golovkin, S.V. ; et al.

Phys.Atom.Nucl. 57 (1994) 1970-1973, 1994.

Inspire Record 365726 DOI 10.17182/hepdata.40602

None

1 data table

Table 1

No description provided.

Measurements of the proton elastic form-factors for 1-GeV/c2 <= Q2 <= 3-GeV/C**2 at SLAC

Walker, R.C. ; Filippone, B. ; Jourdan, J. ; et al.

Phys.Rev.D 49 (1994) 5671-5689, 1994.

Inspire Record 360764 DOI 10.17182/hepdata.22469

We report measurements of the proton form factors GEp and GMp extracted from elastic scattering in the range 1≤Q2≤3 (GeV/c)2 with total uncertainties < 15% in GEp and < 3% in GMp. Comparisons are made to theoretical models, including those based on perturbative QCD, vector-meson dominance, QCD sum rules, and diquark constituents in the proton. The results for GEp are somewhat larger than indicated by most theoretical parametrizations, and the ratios of the Pauli and Dirac form factors Q2(F2pF1p) are lower in value and demonstrate a weaker Q2 dependence than those predictions. A global extraction of the elastic form factors from several experiments in the range 0.1 0.1<Q2<10 (GeV/c)2 is also presented.

6 data tables

Table 1

Point-to-point systematic uncertainty is 0.5%, overall normailzation uncertainty is 1.9%.

Table 2

Point-to-point systematic uncertainty is 0.5%, overall normailzation uncertainty is 1.9%.

Table 3

Point-to-point systematic uncertainty is 0.5%, overall normailzation uncertainty is 1.9%.

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Measurement of kinematic and nuclear dependence of R = sigma-L / sigma-t in deep inelastic electron scattering

Dasu, S. ; deBarbaro, P. ; Bodek, A. ; et al.

Phys.Rev.D 49 (1994) 5641-5670, 1994.

Inspire Record 360765 DOI 10.17182/hepdata.22468

We report results on a precision measurement of the ratio R=σLσT in deep inelastic electron-nucleon scattering in the kinematic range 0.2≤x≤0.5 and 1≤Q2≤10 (GeV/c)2. Our results show, for the first time, a clear falloff of R with increasing Q2. Our R results are in agreement with QCD predictions only when corrections for target mass effects and some additional higher twist effects are included. At small x, the data on R favor structure functions with a large gluon contribution. We also report results on the differences RA−RD and the cross section ratio σAσD between Fe and Au nuclei and the deuteron. Our results for RA−RD are consistent with zero for all x, Q2 indicating that possible contributions to R from nuclear higher twist effects and spin-0 constituents in nuclei are not different from those in nucleons. The ratios σAσD from all recent experiments, at all x, Q2 values, are now in agreement.

31 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Search for excited quarks in p anti-p collisions at s**(1/2) = 1.8-TeV

The CDF collaboration Abe, F. ; Albrow, Michael G. ; Amidei, Dante E. ; et al.

Phys.Rev.Lett. 72 (1994) 3004-3008, 1994.

Inspire Record 360332 DOI 10.17182/hepdata.42507

If quarks are composite particles then excited states are expected. We have searched in pp¯ collisions for excited quarks (q*) which decay to common quarks by emitting a W boson (q*→qW) or a photon (q*→qγ). The simplest model of excited quarks has been excluded for mass M*<540 GeV/c2 at 95% confidence level.

3 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

$P_{\tau}$ and $X_F$ Dependence of the Polarization of $\Sigma^+$ Hyperons Produced by 800-GeV/c Protons

The E761 collaboration Morelos Pineda, Antonio ; Albuquerque, I.F. ; Bondar, N.F. ; et al.

Phys.Rev.D 52 (1995) 3777-3780, 1995.

Inspire Record 360549 DOI 10.17182/hepdata.42500

We utilize the angle and momentum resolution of our apparatus to study the polarization of 375 GeV/c Σ+ hyperons produced by 800 GeV/c protons incident on a Cu target. By examining in detail two of our high statistics data samples, we find evidence for structure in the pt dependence of Σ+ polarization and are able to extract the xF dependence of the Σ+ polarization and compare it with xF behavior in the Λ0 and Ξ− systems.

9 data tables

Table 1

0.9 mrad horizontal sample.

Table 2

2.9 mrad horizontal sample.

Table 3

3.3 mrad horizontal sample.