Studying Gluon Correlations and Nuclear Effects through Transverse Single-Spin Asymmetry Measurements at PHENIX and Promoting an Open Research Infrastructure in High Energy Physics

Abstract

Since the observation of large transverse single-spin asymmetries (TSSAs) in the 1970s, the subject has received much attention. Attempts to explain such asymmetries have provided a critical test of quantum chromodynamics (QCD), as a theoretical explanation requires additional correlations between quark and gluon fields or additional degrees of freedom in parton distribution functions and fragmentation functions that are not present in most perturbative QCD (pQCD) calculations. The Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory is the world's first and only polarized proton collider, with both proton-proton ($p^{uparrow}p$) and proton-nucleus ($p^{uparrow}A$) collisions recorded with polarized protons, allowing for an exploration of such observables at high energies where pQCD is valid and in a setting where gluons are accessible at leading order. This permits the study of twist-3 trigluon correlations within polarized protons, as well as modifications that arise to TSSAs in collision systems with additional nuclear matter. Measurements of TSSAs for midrapidity open heavy flavor electrons in $sqrt{s} = 200$ GeV $p^{uparrow}p$ collisions from the PHENIX experiment are reported in this dissertation to be consistent with zero within measured uncertainties. This production channel provides high sensitivity to gluons in polarized protons, as it proceeds predominantly through gluon-gluon fusion. This measurement provided the first explicit constraints on normalization parameters $lambda_{f}$ and $lambda_{d}$ of the antisymmetric and symmetric trigluon correlators, respectively, to the unpolarized gluon PDF. The $1 sigma$ confidence intervals determined by comparing the theoretical models to data were $lambda_{f} = -0.01 pm 0.03$ GeV and $lambda_{d} = 0.11 pm 0.09$ GeV, implying that trigluon correlations in transversely polarized protons are potentially sizable but also consistent with zero based on the statistical precision of the measurement. Higher precision studies will need to be conducted in the future to pin down the strength of trigluon correlations in transversely polarized protons. First measurements of TSSAs for midrapidity $pi^{0}$ and $eta$ mesons in $sqrt{s_{NN}} = 200$ GeV $p^{uparrow}$Au and $p^{uparrow}$Al collisions from PHENIX are also reported in this dissertation, and are consistent with zero within measured uncertainties. This is compared with data from the same observable in $sqrt{s} = 200$ GeV $p^{uparrow}p$ collisions from which it was determined that no nuclear modification of the TSSA was observed. In addition to analyzing the unique data collected at RHIC, tools were developed to help promote an open research infrastructure in high energy physics by making public the unique data collected by the LHCb experiment at the Large Hadron Collider (LHC) at CERN. An application known as the LHCb Ntuple Wizard provides a means for external users (e.g. theorists and phenomenologists) to make queries of the collected LHCb data through an intuitive web interface, resulting in Ntuples delivered to the CERN Open Data Portal. The detection capabilities of LHCb make it ideal for studying the hadron formation process at the energy frontier, as well as a multitude of other measurements including the core flavor physics program. Providing public access to such datasets not only facilitates the preservation of data, but also has the potential to increase the overall impact and reach of the data to truly optimize the scientific output. The first public release of the LHCb Ntuple Wizard is expected in 2024.