Precision measurement of the deuteron spin structure function g1(d)

The E143 collaboration Abe, K. ; Akagi, T. ; Anthony, P.L. ; et al.
Phys.Rev.Lett. 75 (1995) 25-28, 1995.
Inspire Record 393667 DOI 10.17182/hepdata.19611

We report on a high-statistics measurement of the deuteron spin structure function g1d at a beam energy of 29 GeV in the kinematic range 0.029<x<0.8 and 1<Q2<10 (GeV /c)2. The integral γ1d=∫1g1ddx evaluated at fixed Q2=3 (GeV /c)2 gives 0.042±0.003(stat)±0.004(syst). Combining this result with our earlier measurement of g1p, we find γ1p−γ1n=0.163±0.010(stat)±0.016(syst), which agrees with the prediction of the Bjorken sum rule with O(αs3) corrections, γ1p−γ1n=0.171±0.008. We find the quark contribution to the proton helicity to be Δq=0.30±0.06.

2 data tables

No description provided.

Values of G1 computed assuming G1/F1 is independent of Q**2 and evaluated at Q**2 = 3 GeV**2.


Precision measurement of the proton spin structure function g1(p).

The E143 collaboration Abe, K. ; Akagi, T. ; Anthony, P.L. ; et al.
Phys.Rev.Lett. 74 (1995) 346-350, 1995.
Inspire Record 375737 DOI 10.17182/hepdata.19665

We have measured the ratio g1pF1p over the range 0.029<x<0.8 and 1.3<Q2<10 (GeV/c)2 using deep-inelastic scattering of polarized electrons from polarized ammonia. An evaluation of the integral ∫01g1p(x, Q2)dx at fixed Q2=3 (GeV/c)2 yields 0.127±0.004(stat)±0.010(syst), in agreement with previous experiments, but well below the Ellis-Jaffe sum rule prediction of 0.160±0.006. In the quark-parton model, this implies Δq=0.27±0.10.

2 data tables

No description provided.

Values of G1 computed assuming G1/F1 is independent of Q**2 and using a fixed Q**2 of 3 GeV**2.


Search for diffractive charm production in 800-GeV/c proton - silicon interactions

The Fermilab E653 collaboration Kodama, K. ; Ushida, N. ; Mokhtarani, A. ; et al.
Phys.Lett.B 316 (1993) 188-196, 1993.
Inspire Record 35969 DOI 10.17182/hepdata.28848

A search for charm production in the coherent diffractive dissociation reaction pSi→XSi was carried out for the modes D 0 → K − π + , D 0 → K − π + π + π − , and D + → K − π + π + . No charm signals were observed, and the 90% confidence level upper limit for coherent charm pair production was determined to be 26 μ b per silicon nucleus. The results are interpreted as an upper limit of 0.2% on the amount of intrinsic charm in the proton.

1 data table

90 pct CL upper limits.


Measurement of Beauty Hadron Pair Production in 600-GeV/c $\pi^-$ Emulsion Interactions.

The Fermilab E653 collaboration Kodama, K. ; Ushida, N. ; Mokhtarani, A. ; et al.
Phys.Lett.B 303 (1993) 359-367, 1993.
Inspire Record 363168 DOI 10.17182/hepdata.28925

We report on the production characteristics and total cross section for 9 beauty hadron pairs produced by a 600 GeV/ c π − beam, the first such information in this energy region. The events were detected in the hybrid emulsion spectrometer of Fermilab Experiment E653. The measured pair cross section for all χ F , assuming linear A dependence, is 33±11 (stat.)±6(syst.) nb/nucleon. Fits of the inclusive single-hadron production distribution to the forms d σ d χ F ∝ (1−|χ F −χ 0 |) n and d σ d p T 2 ∝ exp (−bp t 2 ) give n=5.0 −2.1−1.7 +2.7+1.7 , χ 0 =0.06 −0.07−0.03 +0.06+0.02 , and b=0.13 −0.04−0.02 +0.05+0.02 ( GeV /c −2 . .The pairs tend to be produced back-to-back.

3 data tables

Cross section over all x assuming A**1 nuclear dependence.

Fit to data of form dsig/dx ^ (1-ABS(X-X0))**N yields X0 = 0.06 +0.06,-0.07(DSYS=+0.02,-0.03) and N = 5.0 +2.7,-2.1(DSYS=+-1.7).

Fit to data of form dsig/dPT**2 ^ exp(-B*PT**2) yields B = 0.13 +0.05,-0.04(DSYS=+-0.02).


Charm Meson Production in 600-GeV/c $\pi^-$ Emulsion Interactions

The Fermilab E653 collaboration Kodama, K. ; Ushida, N. ; Mokhtarani, A. ; et al.
Phys.Lett.B 284 (1992) 461-470, 1992.
Inspire Record 32383 DOI 10.17182/hepdata.29154

We present total and differential cross sections for charm mesons produced in 600 GeV/ c π - emulsion interactions. Fits to d 2 σ / dx F dp T 2 ∞ (1−| x F |) n exp (- bp T 2 ) for 676 electronically reconstructed D mesons with x F >0 give n =4.25±0.24 ( stat .)±0.23 ( syst .) and b =0.76±0.03±0.03 ( GeV / c ) -2 . The total inclusive D + and D 0 cross sections are σ ( π - N → D ± ; x F >0) = 8.66±0.46±1.96 μb nucleon and σ(π - N→D 0 D 0 ; x F >0)=22.05±1.37±4.82μb nucleonk, where a linear dependence on the mean atomic weight of the target is assumed. These results are compared to next-to-leading order QCD predictions.

2 data tables

Linear A-dependence. Different modes of the charm mesons detection were used (see text for detail). The differential cross section is fitted by the equation : D2(SIG)/D(XL)/D(PT**2) = CONST*(1-XL)**POWER*EXP(-SLOPE*PT**2).

Linear A-dependence.


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

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

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


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

No description provided.


POLARIZATION OF LAMBDA0 HYPERONS IN INCLUSIVE PRODUCTION BY 12-GEV PROTONS ON TUNGSTEN

Abe, F. ; Hara, K. ; Kim, N. ; et al.
Phys.Rev.Lett. 50 (1983) 1102-1105, 1983.
Inspire Record 192461 DOI 10.17182/hepdata.20570

The authors have measured the polarization of 2.4×105 Λ0 hyperons in inclusive production by 12-GeV protons on tungsten at three production angles, 3.5°, 6.5°, and 9.5°. In terms of Feynman's xF and transverse momentum of Λ0, the kinematical range is 0.3<~xF<~0.8 and 0.4<~pT<~1.6 GeV/c. The observed polarization does not depend strongly on xF and increases linearly with pT to 16% at pT=1.0 GeV/c, showing a tendency to level off above that point.

6 data tables

No description provided.

No description provided.

No description provided.

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