OGLE-2019-BLG-0304: Competing Interpretations between a Planet–binary Model and a Binary-source + Binary-lens Model

We analyze the microlensing event OGLE-2019-BLG-0304, whose light curve exhibits two distinctive features: a deviation in peak region and second bump appearing ?61 days after main peak. Although binary-lens model can explain overall features, it leaves subtle but noticeable residuals region. find that be explained by presence of either planetary companion located close to primary binary lens (3L1S model) or an additional source (2L2S model). 3L1S is favored over 2L2S model, with ??2 ? 8, securely resolving degeneracy between models difficult currently available photometric data. According interpretation, system, which planet mass S-type orbit around composed stars masses . however, G- K-type giant low-mass M dwarf brown , respectively. The illustrates need for thorough testing interpretation lensing events complex features curves.