Inclusive double-helicity asymmetries in neutral pion and eta meson production in $\vec{p}+\vec{p}$ collisions at $\sqrt{s}=200$ GeV

The PHENIX collaboration Adare, A. ; Aidala, C. ; Ajitanand, N.N. ; et al.
Phys.Rev.D 90 (2014) 012007, 2014.
Inspire Record 1282448 DOI 10.17182/hepdata.64716

Results are presented from data recorded in 2009 by the PHENIX experiment at the Relativistic Heavy Ion Collider for the double-longitudinal spin asymmetry, $A_{LL}$, for $\pi^0$ and $\eta$ production in $\sqrt{s} = 200$ GeV polarized $p$$+$$p$ collisions. Comparison of the $\pi^0$ results with different theory expectations based on fits of other published data showed a preference for small positive values of gluon polarization, $\Delta G$, in the proton in the probed Bjorken $x$ range. The effect of adding the new 2009 \pz data to a recent global analysis of polarized scattering data is also shown, resulting in a best fit value $\Delta G^{[0.05,0.2]}_{\mbox{DSSV}} = 0.06^{+0.11}_{-0.15}$ in the range $0.05<x<0.2$, with the uncertainty at $\Delta \chi^2 = 9$ when considering only statistical experimental uncertainties. Shifting the PHENIX data points by their systematic uncertainty leads to a variation of the best-fit value of $\Delta G^{[0.05,0.2]}_{\mbox{DSSV}}$ between $0.02$ and $0.12$, demonstrating the need for full treatment of the experimental systematic uncertainties in future global analyses.

9 data tables

PI0 ASYM(LL) measurements from 2005.

PI0 ASYM(LL) measurements from 2006.

PI0 ASYM(LL) measurements from 2009.

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Polarization of Lambda and anti-Lambda produced by 800-GeV protons

Ramberg, E.J. ; Bock, G.J. ; Coleman, R. ; et al.
Phys.Lett.B 338 (1994) 403-408, 1994.
Inspire Record 372108 DOI 10.17182/hepdata.42451

We have measured the polarization of Λ and Λ hyperons produced by 800 GeV protons on a Be target at a fixed targeting angle of 4.8 mrad. Comparison with previous data at 400 GeV production energy and twice the targeting angle shows no significant energy dependence for the Λ polarization. This is in striking contrast to the energy dependence found for σ + and Ξ − polarizations. We find no evidence for Λ polarization at 800 GeV.

2 data tables

Errors are combined statistics and systematics.

No description provided.


Polarization of cumulative protons in the reaction gamma A --> p X.

Avakyan, R.O. ; Avakian, E.O. ; Avdalyan, G.A. ; et al.
Sov.J.Nucl.Phys. 51 (1990) 999-1000, 1990.
Inspire Record 306076 DOI 10.17182/hepdata.17310

None

3 data tables

No description provided.

No description provided.

No description provided.


Polarization of cumulative protons in the reaction gamma A --> p X.

Avakian, R.O. ; Avetisian, A.E. ; Arestakesian, G.A. ; et al.
Sov.J.Nucl.Phys. 49 (1989) 292-294, 1989.
Inspire Record 284675 DOI 10.17182/hepdata.17336

None

2 data tables

No description provided.

No description provided.


Differential Cross-sections and Analyzing Powers for Small Angles $N P$ Elastic Scattering Between 376-{MeV} and 1135-{MeV}

Silverman, B.H. ; Lugol, J.C. ; Saudinos, J. ; et al.
Nucl.Phys.A 499 (1989) 763-788, 1989.
Inspire Record 264337 DOI 10.17182/hepdata.36902

We have measured absolute differential cross sections and analyzing powers for neutron-proton elastic scattering for momentum transfer 0.01 < | t |< 0.08 (GeV/ c ) 2 at several energies between 378 and 1135 MeV. The ionization chamber IKAR filled with methane was used as both a gas target and recoil detector. For the analyzing-power measurements the scattered neutron was detected in scintillation counters in coincidence with the recoil proton detected in IKAR. Special care was taken to ensure a precise absolute normalization of the cross sections, with overall systematic uncertainties of 4–7%.

19 data tables

TOTAL SYSTEMATIC UNCERTAINTIES IN D(SIG)/D(T)=6.4 PCT.

TOTAL SYSTEMATIC UNCERTAINTIES IN D(SIG)/D(T)=5.4 PCT.

TOTAL SYSTEMATIC UNCERTAINTIES IN D(SIG)/D(T)=6.5 PCT.

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Analyzing Powers in Free $N$ (Polarized) $P$ Forward Elastic Scattering at Energies From 630-{MeV} to 1000-{MeV}

Korolev, G.A. ; Khanzadeev, A.V. ; Petrov, G.E. ; et al.
Phys.Lett.B 165 (1985) 262-264, 1985.
Inspire Record 228528 DOI 10.17182/hepdata.30310

The analysing powers in free →n p forward elastic scattering have been measured for incident neutron energies of 633, 784, 834, 934 and 985 MeV, and for momentum transfer 0.01 < ‖ t ‖ < 0.10 ( GeV / c ) 2 . The experiment used a recoil detector ionisation chamber which served at the same time as a gas target, and scintillation counters to measure the asymmetry of the scattered neutrons.

5 data tables

No description provided.

No description provided.

No description provided.

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MEASUREMENT OF THE POLARIZATION OF CUMULATIVE PROTONS IN gamma A ---> p X REACTION

Avakian, R.O. ; Avakian, E.O. ; Avetisian, A.E. ; et al.
Yad.Fiz. 42 (1985) 667-670, 1985.
Inspire Record 210380 DOI 10.17182/hepdata.17606

None

1 data table

Axis error includes +- 7/7 contribution.


MEASUREMENT OF ASYMMETRY IN CROSS-SECTION OF GAMMA P ---> P PI0 REACTION IN THE RESONANCE REGION. (IN RUSSIAN)

Avakian, R.O. ; Avetisian, A.E. ; Bagdasaryan, A.S. ; et al.
Yad.Fiz. 38 (1983) 1196-1198, 1983.
Inspire Record 200187 DOI 10.17182/hepdata.17731

None

1 data table

Axis error includes +- 0.0/0.0 contribution (?////DUE TO ERRORS IN PHOTON POLARIZATION).


MEASUREMENT OF THE ASYMMETRY OF THE REACTION gamma p ---> p pi0 CROSS-SECTION FOR PION PRODUCTION ANGLES IN CMS 65-degrees TO 80-degrees IN THE RESONANCE ENERGY RANGE

Avakian, R.O. ; Bagdasaryan, A.S. ; Vartapetian, G.A. ; et al.
Sov. J. Contemp. Phys. 19 ( 1984) No. 1 46-48. ( Izv. Akad. Nauk Arm. SSR 19 ( 1984) No. 1 50-53) and Erevan Phys. Inst. - EFI-674(64)-83 (83,REC.JAN.84) 13p, 1983.
Inspire Record 195991 DOI 10.17182/hepdata.18465

None

3 data tables

No description provided.

No description provided.

No description provided.


MEASUREMENT OF POLARIZATION OF RECOIL PROTONS IN PI0 PHOTOPRODUCTION FOR THETA* (PI0) = 60-degrees IN RESONANCE REGION. (IN RUSSIAN)

Avakian, R.O. ; Avakian, E.O. ; Avetisian, A.E. ; et al.
Sov.J.Nucl.Phys. 37 (1983) 199-201, 1983.
Inspire Record 183972 DOI 10.17182/hepdata.17739

None

1 data table

Axis error includes +- 0.0/0.0 contribution (?////NO DISCUSSION OF ERRORS AT ALL).