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.

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PI0 ASYM(LL) measurements from 2005.

PI0 ASYM(LL) measurements from 2006.

PI0 ASYM(LL) measurements from 2009.

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Measurements of double-helicity asymmetries in inclusive $J/\psi$ production in longitudinally polarized $p+p$ collisions at $\sqrt{s}=510$ GeV

The PHENIX collaboration Adare, A. ; Aidala, C. ; Ajitanand, N.N. ; et al.
Phys.Rev.D 94 (2016) 112008, 2016.
Inspire Record 1467456 DOI 10.17182/hepdata.82575

We report the double helicity asymmetry, $A_{LL}^{J/\psi}$, in inclusive $J/\psi$ production at forward rapidity as a function of transverse momentum $p_T$ and rapidity $|y|$. The data analyzed were taken during $\sqrt{s}=510$ GeV longitudinally polarized $p

1 data table match query

$A_{LL}^{J/\psi}$ as a function of $p_T$ or $|y|$. $N_{J/\psi}^{2\sigma}$ is the $J/\psi$ counting within its $2\sigma$ mass window. The column of Type A systematic uncertainties are a statistically weighted quadratic combination of the background fraction and run grouping uncertainties. $\Delta A_{LL}$ (Rel. Lumi.) is the global systematic uncertainty from relative luminosity measurements. $\Delta A_{LL}$ (Polarization) is the systematic uncertainty from the beam polarization measurement: a zero indicates an uncertainty $< 0.001$.


Polarization of Charmed $\Lambda(c$)+ Baryons Produced in Neutron - Carbon Interactions

The BIS-2 collaboration Aleev, A.N. ; Arefev, V.A. ; Balandin, V.P. ; et al.
Yad.Fiz. 43 (1986) 619-623, 1986.
Inspire Record 209855 DOI 10.17182/hepdata.39660

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2 data tables match query

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