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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.

Measurement of the Branching Ratio for $\Xi^- \to \Sigma^- \gamma$ Radiative Decay

The E761 collaboration Dubbs, T. ; Albuquerque, I.F. ; Bondar, N.F. ; et al.

Phys.Rev.Lett. 72 (1994) 808-811, 1994.

Inspire Record 358245 DOI 10.17182/hepdata.18430

We have measured the branching ratio for the hyperon radiative decay Ξ−→Σ−γ from a sample of 211±33 events obtained in the polarized 375 GeV/c charged hyperon beam at Fermilab. We find B(Ξ−→Σ−γ/Ξ−→Λ0π−)=(1.22±0.23±0.06)×10−4 where the quoted errors are statistical and systematic, respectively. We have also obtained an indication that the sign of the asymmetry parameter of this decay is positive.

1 data table

Table 1

Polarized 375 GeV charged hyperon beam at Fermilab. Sample of 211 +- 33 events.

Polarization of $\Sigma^+$ and $\bar{\Sigma^-}$ Hyperons Produced by 800-GeV/c Protons

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

Phys.Rev.Lett. 71 (1993) 2172-2175, 1993.

Inspire Record 356301 DOI 10.17182/hepdata.19722

We have mesured the polarization of 375-GeV/c Σ+ and Σ¯ − hyperons produced by 800-GeV/c protons incident on a Cu target. We find that the Σ+ polarization rises with increasing pt to a maximum of 16% at pt=1.0 GeV/c and then decreases to 10% at pt=1.8 GeV/c. We compare this Σ+ polarization with data at lower energies. The Σ¯ − polarization has been measured for the first time. It has the same sign as the Σ+ but smaller magnitude in a similar kinematical region.

4 data tables

Table 1

Data from Horizontal targeting.

Table 2

Data from Vertical targeting.

Table 3

Data from Horizontal targeting.

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Charm Pair Correlations in 800-GeV/c Proton - Emulsion Interactions

The Fermilab E653 collaboration Kodama, K. ; Ushida, N. ; Mokhtarani, A. ; et al.

Phys.Lett.B 263 (1991) 579-583, 1991.

Inspire Record 30878 DOI 10.17182/hepdata.47103

We present results on charm pair correlations measured in proton-emulsion interactions at s =38.7 GeV. The predictions of leading order QCD for the distributions in invariant mass, rapidity gap, x F , and polar angle in the charm pair CMS are qualitatively consistent with our measurements. The mean p T of the pairs is equal within errors to that measured in dilepton production at the same energy and mass range.

1 data table

Table 1

No description provided.

Charm Meson Production in 800-GeV/c Proton - Emulsion Interactions

The Fermilab E653 collaboration Kodama, K. ; Ushida, N. ; Mokhtarani, A. ; et al.

Phys.Lett.B 263 (1991) 573-578, 1991.

Inspire Record 30879 DOI 10.17182/hepdata.47110

We report results on D 0 and D + production in proton-emulsion interactions at s =38.7 GeV. A fit to the form (1−| x F |) n exp (−bp 2 T ) yields n=6.9 +1.9 −1.8 and b=0.84 +0.10 −0.08 (GeV/ c ) −2 . The total inclusive cross section, is assuming linear A dependence, is measured to be 38±3(stat.) ±13 (sys.) μ b for the D 0 and 38±9±14 μ b for the D + . A comparison of these results with previous measurements indicates that nuclear effects do not strongly influence charm production. The predictions of QCD are in good agreement with our data.

3 data tables

Table 1

The differential cross section is fitted by the equation : D2(SIG)/D(XL)/D(PT**2) = CONST*(1-XL)**POWER*EXP(-SLOPE*PT**2).

Table 2

The differential cross section is fitted by the equation : D2(SIG)/D(XL)/D(PT**2) = CONST*(1-XL)**POWER*EXP(-SLOPE*PT**2).

Table 3

Linear A-dependence. Different modes of the charm mesons detection were used (see text for detail).

COMPARISON OF DIRECT PHOTON PRODUCTION IN P P COLLISIONS AT S**(1/2) = 30.6-GEV AND 53.2-GEV

Amaldi, E. ; Beneventano, M. ; Borgia, B. ; et al.

Phys.Lett.B 84 (1979) 360-362, 1979.

Inspire Record 146580 DOI 10.17182/hepdata.27321

We present data obtained at the ISR, on the determination of the ratio R = γ π 0 at s = 30.6 GeV and we compare the results with our previous measurement at s = 53.2 GeV. The ratio R = γ π 0 integrated over the interval 0.1 ⩽ χ T ⩽ 0.2 is (1.6 ± 0.5) × 10 −2 and we obtain an indication of a universal χ T dependence.

1 data table

Table 1

No description provided.

INCLUSIVE ETA PRODUCTION IN P P COLLISION AT ISR ENERGIES

Amaldi, E. ; Beneventano, M. ; Borgia, B. ; et al.

Nucl.Phys.B 158 (1979) 1-10, 1979.

Inspire Record 145095 DOI 10.17182/hepdata.34663

We report on the experimental results obtained at the ISR for the η particle production at 90° and √ s = 30.6 and 53.2 GeV. We determine the invariant cross section and the p t distribution in the interval 1 ⩽ p t ⩽ 5 GeV/ c . We find that the p t distribution has the same shape of the π 0 production and differ from it by a constant factor R 90° = 0.5 ± 0.07.

1 data table

Table 1

No description provided.

SINGLE DIRECT PHOTON PRODUCTION IN P P COLLISIONS AT S**(1/2) = 53.2-GEV IN THE P(T) INTERVAL 2.3-GEV/C TO 5.7-GEV/C

Amaldi, E. ; Beneventano, M. ; Borgia, B. ; et al.

Nucl.Phys.B 150 (1979) 326-344, 1979.

Inspire Record 145596 DOI 10.17182/hepdata.34796

We report the results of an experiment made at the CERN ISR to investigate the possible diret production of single photons in pp collisions at √ s = 53.2 GeV at 90° and in the p t interval 2.3 to 5.7 GeV/ c . The value of the ratio R = n γ / n π 0 is compatible with zero for low p t ⪅ 3 GeV/ c but, in spite of the large error, shows a trend to increase for larger p t .

3 data tables

Table 1

THIS USES THE SO-CALLED D2L TRIGGER (SEE PAPER).

Table 2

THIS USES THE SO-CALLED D2MAX TRIGGER (SEE PAPER).

Table 3

THIS USES THE SO-CALLED D2MAX TRIGGER (SEE PAPER).