The study of the origin of transverse single-spin asymmetries has triggered the development of the twist-3 formalism and the transverse-momentum-dependent parton distribution functions (TMDs).
Measurements of the azimuthal distribution of identified hadrons within a jet in transversely polarized hadronic interactions provide opportunities to study TMD physics, such as the Collins effect which involves the quark transversity and the Collins fragmentation functions.
STAR has reported measurements of the Collins asymmetries from jet + $\pi^{\pm}$ production in transversely polarized ${pp}$ collisions at a center-of-mass energy of $\sqrt{s}$ = 500 GeV based on data taken in 2011 with an integrated luminosity of 23 $\mathrm{pb}^{-1}$. Additionally, an extensive measurement of azimuthal transverse single-spin asymmetries of inclusive jets and hadrons within jets from transversely polarized ${pp}$ collisions at $\sqrt{s}$ = 200 GeV was performed using data from 2012 and 2015.
In 2017, STAR collected a significantly larger ${pp}$ dataset with an integrated luminosity of 320 $\mathrm{pb}^{-1}$ at $\sqrt{s}$ = 510 GeV, which will further improve the precision of the transverse single-spin asymmetry measurements, especially in the high jet transverse momentum region.
In this contribution, we report the preliminary results of azimuthal transverse single-spin asymmetries for inclusive jets and charged pions within jets from transversely polarized ${pp}$ collisions at $\sqrt{s}$ = 510 GeV.