Low-lying doubly heavy baryons: Regge relation and mass scaling
i=Q Q ,q (A5) The boundary condition of string at ends linked to heavy quark gives a ω = (mbareQ Q )vQ Q 1 − v2Q Q = MQQvQQ . 1 − v2Q Q (A6) As the diquark Q Q is very heavy and moves nonrela- tivistically