Measurements of Single and Double Spin Asymmetry in $\mathit{\text{pp}}$ Elastic Scattering in the CNI Region with Polarized Hydrogen Gas Jet Target

Precise measurements of the single spin asymmetry, $A_N$ and the double spin asymmetry, $A_{NN}$, in proton-proton ($\mathit{\text{pp}}$) elastic scattering in the region of four-momentum transfer squared $0.001<-t<0.032(\mathrm{G}\mathrm{e}\mathrm{V}\mathrm{/}c{)}^2$ have been performed using a polarized atomic hydrogen gas jet target and the RHIC polarized proton beam at 24 GeV/$c$ and 100 GeV/$c$. The polarized gaseous proton target allowed us to achieve the measurement of $A_{NN}$ in the CNI region for the first time. Our results of $A_N$ and $A_{NN}$ provide significant constraints to determine the magnitude of poorly known hadronic single and double spin-flip amplitudes at this energy.