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In this work, we study the contributions of the intermediate bottomoniumlike $Z_b$ states and the bottom meson loops in the heavy quark spin flip transitions $Upsilon(4S) to h_b(1P,2P) pi^+pi^-$. Depending on the constructive or destructive interferences between the $Z_b$-exchange and the bottom meson loops mechanisms, we predict two possible branching ratios for each process: BR$_{Upsilon(4S) to h_b(1P)pi^+pi^-}simeqbig(1.2^{+0.8}_{-0.4}times10^{-6}big)$ or $big( 0.5^{+0.5}_{-0.2}times10^{-6}big)$, and BR$_{Upsilon(4S) to h_b(2P)pi^+pi^-}simeq big(7.1^{+1.7}_{-1.1}times10^{-10}big)$ or $big( 2.4^{+0.2}_{-0.1}times10^{-10}big)$. The bottom meson loops contribution is found to be much larger than the $Z_b$-exchange contribution in the $Upsilon(4S) to h_b(1P) pipi$ transitions, while it can not produce decay rates comparable to the heavy quark spin conserved $Upsilon(4S) to Upsilon(1S,2S) pipi$ processes. We also predict the branch fractions of $psi(3S,4S) to h_c(1P)pi^+pi^-$ contributed from the charm meson loops.
We study the dipion transitions $Upsilon(4S) rightarrow Upsilon(nS) pi^+pi^-$ $(n=1,2)$. In particular, we consider the effects of the two intermediate bottomoniumlike exotic states $Z_b(10610)$ and $Z_b(10650)$ as well as bottom meson loops. The str
Using a sample of 122 million Upsilon(3S) events recorded with the BaBar detector at the PEP-II asymmetric-energy e+e- collider at SLAC, we search for the $h_b(1P)$ spin-singlet partner of the P-wave chi_{bJ}(1P) states in the sequential decay Upsilo
The dipion transitions $Upsilon(2S,3S,4S) to Upsilon(1S,2S)pipi$ are systematically studied by considering the mechanisms of the hadronization of soft gluons, exchanging the bottomoniumlike $Z_b$ states, and the bottom-meson loops. The strong pion-pi
We calculate the cross sections and final state distributions for the processes e^+ e^- --> Upsilon(1S) (pi^+ pi^-, K^+ K^-, eta pi^0) near the Upsilon(5S) resonance based on the tetraquark hypothesis. This framework is used to analyse the data on th
Using a sample of $771.6 times 10^{6}$ $Upsilon(4S)$ decays collected by the Belle experiment at the KEKB $e^+e^-$ collider, we observe for the first time the transition $Upsilon(4S) to eta h_b(1P)$ with the branching fraction ${cal B}[Upsilon(4S) to