Eidelman, S.I
PHENIX
single-spin asymmetry
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Single-spin asymmetry of $J/\psi$ production in $p$$+$$p$, $p$$+$Al, and $p$$+$Au collisions with transversely polarized proton beams at $\sqrt{s_{_{NN}}}=200$ GeV

The PHENIX collaboration Aidala, C. ; Akiba, Y. ; Alfred, M. ; et al.
Phys.Rev.D 98 (2018) 012006, 2018.
Inspire Record 1671782 DOI 10.17182/hepdata.142340

We report the transverse single-spin asymmetries of $J/\psi$ production at forward and backward rapidity, $1.2<|y|<2.2$, as a function of $J/\psi$ transverse momentum ($p_T$) and Feynman-$x$ ($x_F$). The data analyzed were recorded by the PHENIX experiment at the Relativistic Heavy Ion Collider in 2015 from $p$$+$$p$, $p$$+$Al, and $p$$+$Au collisions with transversely polarized proton beams at $\sqrt{s_{_{NN}}}=200$ GeV. At this collision energy, single-spin asymmetries for heavy-flavor particle production of $p$$+$$p$ collisions provide access to the spin-dependent gluon distribution and higher-twist correlation functions inside the nucleon, such as the gluon Qiu-Sterman and trigluon correlation functions. Proton+nucleus collisions offer an excellent opportunity to study nuclear effects on the correlation functions. The data indicate negative asymmetries at the two-standard-deviation level in the $p$$+$Au data for $p_T<2$ GeV/$c$ at both forward and backward rapidity, while in $p$$+$$p$ and $p$$+$Al collisions the asymmetries are consistent with zero within the range of experimental uncertainties.

8 data tables
Figure 4a

Forward [$x_F$ > 0] $A^{J/\psi}_N$ vs low $p_T$ for $p$+$p$, $p$+Al, and $p$+Au collisions.

Figure 4b

Forward [$x_F$ > 0] $A^{J/\psi}_N$ vs high $p_T$ for $p$+$p$, $p$+Al, and $p$+Au collisions.

Figure 4c

Backward [$x_F$ < 0] $A^{J/\psi}_N$ vs low $p_T$ for $p$+$p$, $p$+Al, and $p$+Au collisions.

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Cross section and longitudinal single-spin asymmetry $A_L$ for forward $W^{\pm}\rightarrow\mu^{\pm}\nu$ production in polarized $p$$+$$p$ collisions at $\sqrt{s}=510$ GeV

The PHENIX collaboration Adare, A. ; Aidala, C. ; Ajitanand, N.N. ; et al.
Phys.Rev.D 98 (2018) 032007, 2018.
Inspire Record 1667398 DOI 10.17182/hepdata.141628

We have measured the cross section and single spin asymmetries from forward $W^{\pm}\rightarrow\mu^{\pm}\nu$ production in longitudinally polarized $p$$+$$p$ collisions at $\sqrt{s}=510$ GeV using the PHENIX detector at the Relativistic Heavy Ion Collider. The cross sections are consistent with previous measurements at this collision energy, while the most forward and backward longitudinal single spin asymmetries provide new insights into the sea quark helicities in the proton. The charge of the W bosons provides a natural flavor separation of the participating partons.

2 data tables
Table 3

Single-spin asymmetries at forward $A^{FW}_L$ and backward $A^{BW}_L$ rapidities for $p$+$p$ collisions at $\sqrt{s}$ = 510 GeV for results in 2013 and 2012, plus combined results for both years.

Conclusion

The total $W$ boson production cross sections for $p$+$p$ collisions at $\sqrt{s}$ = 510 GeV for $\sigma$($W^+$ $\rightarrow$ $\mu^+$) and $\sigma$($W^-$ $\rightarrow$ $\mu^-$).