Prospects for observing the lowest-lying odd-parity Σ c and Σ b baryons

There exist candidates for the negative-parity states Λc,b(1/2-,3/2-) consisting of an isospin-zero, spin-zero light diquark [ud] with one unit of orbital angular momentum with respect to a c,b quark. However, there exists only one candidate for the orbital excitations of the Σc(1/2+) and Σc*(3/2+), and none for the orbital excitations of Σb(1/2+) or Σb*(3/2+). We extend a previous discussion of odd-parity Λc,b states and explore some patterns of the odd-parity Σc,b baryons consisting of a light isospin-one nonstrange diquark (uu,ud,dd) in a state of L=1 with respect to the spin-1/2 heavy quark (c,b).