Weak Decays of Doubly-Heavy Tetraquarks $b\bar{c}q\bar{q}$

Abstract

We study the weak decays of exotic tetraquark states $b\bar{c}q\bar{q}$ with two heavy quarks. Under the SU(3) symmetry for light quarks, these tetraquarks can be classified into an octet plus a singlet: $3⨂\bar{3}=1⨁8$. We will concentrate on the octet tetraquarks with $J^P=0^{+}$, and study their weak decays, both semileptonic and nonleptonic. Hadron-level effective Hamiltonian is constructed according to the irreducible representations of the SU(3) group. Expanding the Hamiltonian, we obtain the decay amplitudes parameterized in terms of a few irreducible quantities. Based on these amplitudes, relations for decay widths are derived, which can be tested in future. We also give a list of golden channels that can be used to look for these states at various colliders.

14 pages,3 figures