Investigation on the Ω(2012) from QCD sum rules

We study the recently observed Ω(2012) baryon in QCD sum rules. We construct the P-wave Ω baryon currents with a covariant derivative, and perform spin projection to obtain the currents with total spin 1/2 and 3/2. We then apply the parity-projected QCD sum rules to separate the contributions of the positive and negative parity states. We extract the masses of JP = 1/2⁻ and 3/2⁻ states to be M1/2⁻ = 2.07+0.07-0.07~GeV and M3/2⁻ = 2.05+0.09-0.10~GeV. Both results are in good agreement with the experimental result. Therefore, it is likely that the Ω(2012) is a negative parity state, which is interpreted as a P-wave excited state in the quark model. However, its spin is not determined in the present analysis, which can be done by detailed study on its decay properties.