Effects of odderon spin on helicity amplitudes in $pp$ elastic scattering

EPJ C, 83 (2023) 953 In recent years, the discovery of the odderon, a colorless $C$-odd gluonic compound, has been confirmed in the TOTEM and D0 collaborations. However, the spin quantum number of the odderon remains unidentified. In this work, we aim to attribute a spin of $J=3$ to the odderon in $pp$ elastic scattering by calculating the helicity amplitudes and the corresponding complex parameter $r_5$, the ratio of helicity's single-flip to non-flip amplitudes, for the spin-3 tensor odderon with the standard spin-2 tensor pomeron exchanges. Then, we apply these results to the constraints obtained from the STAR experiment at RHIC. By comparing to the contributions of the spin-1 vector odderon and spin-2 tensor pomeron, we demonstrate that the spin-3 tensor odderon, i.e. $J=3$, provides a better explanation for the observable in $pp$ elastic scattering.