1110.1333 (Ahmed Ali et al.)

Tetraquark Interpretation of the Charged Bottomonium-like states
Z_b^+-(10610) and Z_b^+-(10650) and Implications    [PDF]

Ahmed Ali, Christian Hambrock, Wei Wang

We present a tetraquark interpretation of the charged bottomonium-like states
Z+-_b(10610) and Z+-_b(10650), observed by the Belle collaboration in the pi+-
Upsilon(nS) (n=1,2,3) and pi+- h_b(mP) (m=1,2) invariant mass spectra from the
data taken near the peak of the Upsilon(5S). In this framework, the underlying
processes involve the production and decays of a vector tetraquark Y_b(10890),
e+e- --> Y_b(10890) --> [Z+-_b(10610)pi-+, Z+-_b(10650)pi-+] followed by the
decays [Z+-_b (10610), Z+-_b (10650)] --> pi+- Upsilon(nS), pi+- h_b(mP).
Combining the contributions from the meson loops and an effective Hamiltonian,
we are able to reproduce the observed masses of the Z+-_b(10610) and
Z+-_b(10650). The analysis presented here is in agreement with the Belle data
and provides crucial tests of the tetraquark hypothesis. We also calculate the
corresponding meson loop effects in the charm sector and find them dynamically
suppressed. The charged charmonium-like states Z+-_c(3752) and Z+-_c(3882) can
be searched for in the decays of the J^{PC}=1^{--} tetraquark state Y(4260) via
Y(4260) --> Z+-_c(3752)pi-+ and Y(4260) --> Z+-_c(3882)pi-+, with the
subsequent decays (Z+-_c(3752),Z+-_c(3882)) --> (J/psi, h_c)pi+-.

View original: http://arxiv.org/abs/1110.1333