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We report measurements of $\mathrm{\Upsilon }\left(1S\right)$, $\mathrm{\Upsilon }\left(2S\right)$and $\mathrm{\Upsilon }\left(3S\right)$production in $p+p$collisions at $\sqrt{s}=500\mathrm{GeV}$by the STAR experiment in year 2011, corresponding to an integrated luminosity ${\mathcal{L}}_{\mathrm{int}}=13{\mathrm{pb}}^{-1}$. The results provide precise cross sections, transverse momentum ( $p_{\mathrm{T}}$) and rapidity ( $y$) spectra, as well as cross section ratios for $p_{\mathrm{T}}<10\mathrm{GeV}/\mathrm{c}$and $\left|y\right|<1$. The dependence of the $\mathrm{\Upsilon }$yield on charged particle multiplicity has also been measured, offering new insights into the mechanisms of quarkonium production. The data are compared to various theoretical models: the color evaporation model (CEM) accurately describes the $\mathrm{\Upsilon }\left(1S\right)$production, while the color glass $\mathrm{condensate}+\text{nonrelativistic}$quantum chromodynamics ( $\mathrm{CGC}+\mathrm{NRQCD}$) model overestimates the data, particularly at low $p_{\mathrm{T}}$. Conversely, the color singlet model (CSM) underestimates the rapidity dependence. These discrepancies highlight the need for further development in understanding the production dynamics of heavy quarkonia in high-energy hadronic collisions. The trend in the multiplicity dependence is consistent with CGC/saturation and string percolation models or $\mathrm{\Upsilon }$production happening in multiple parton interactions modeled by 8. 

The STAR Collaboration reports precise measurements of the longitudinal double-spin asymmetry, $A_{LL}$, for dijet production with at least one jet at intermediate pseudorapidity $0.8<{\eta }_{\text{jet}}<1.8$in polarized proton-proton collisions at a center-of-mass energy of 200 GeV. This study explores partons scattered with a longitudinal momentum fraction ( $x$) from 0.01 to 0.5, which are predominantly characterized by interactions between high- $x$valence quarks and low- $x$gluons. The results are in good agreement with previous measurements at 200 GeV with improved precision and are found to be consistent with the predictions of global analyses that find the gluon polarization to be positive. In contrast, the negative gluon polarization solution from the JAM Collaboration is found to be strongly disfavored.