相关论文: Heavy quark spin structure in Z_b resonances
Recently the Belle collaboration discovered two resonances, Zb(10610) and Zb(10650), that lie very close to the B\bar{B}^* and B^*\bar{B}^* thresholds, respectively. It is natural to suppose that these are molecular states of bottom and…
Whether molecular states indeed exist in nature has been disputed for a long time. Several new resonances have been observed in the recent experiments and they seem to be of exotic structures and some of them have been proposed to be…
We study the implications of the heavy-quark spin symmetry for the possible spin partners of the exotic states $Z_b(10610)$ and $Z_b(10650)$ in the spectrum of bottomonium. We formulate and solve numerically the coupled-channel equations…
In general, resonances are obtained by the Breit-Wigner parameterization. However, it is not entirely appropriate to use this parameterization with near-threshold resonances such as the $Z_b(10610)$ and the $Z_b(10650)$, as Breit-Wigner…
It is argued that the recent Belle data, consistent with no activity in the spectrum of the $B^* \bar B + B \bar B^*$ pairs at the mass of the $Z_b(10650)$ resonance, imply that the part of the interaction between heavy mesons that depends…
The isovector bottomoniumlike exotic resonances $Z_b(10610)$ and $Z_b(10650)$ are very close to the thresholds of heavy meson pairs $B \bar B^* \, ( \bar B B^*)$ and $B^* \bar B^*$, and are naturally understood as `molecular' states made of…
The resonance $Z_b(10610)$ is investigated as the diquark-antidiquark $ Z_b=[bu][\overline b \overline d]$ state with spin-parities $J^{PC}=1^{+-}$. The mass and current coupling of the resonance $Z_b(10610)$ are evaluated using QCD…
Spectrum of the doubly heavy tetraquarks, $bb\bar q\bar q$, is studied in a constituent quark model. Four-body problem is solved in a variational method where the real scaling technique is used to identify resonant states above the…
The recently observed narrow resonance $Z_{b}(10610)$ is examined with the assumptions both as a $B^{*}\bar{B}$ molecular state and a $[bd][\bar{b}\bar{u}]$ tetraquark state with quantum numbers $I^{G}J^{P}=1^{+}1^{+}$. Possible…
Motivated by the two charged bottomonium-like resonances $Z_b$(10610) and $Z_b$(10650) newly observed by the Belle collaboration, the possible molecular states composed of a pair of heavy mesons, $B\bar{B}, B\bar{B}^*, B^*\bar{B}^*,…
The implementation of the heavy quark spin symmetry in possible molecular states at the mixed bottom-charm threshold is somewhat different from that at the open charm or bottom thresholds. In particular it depends on two parameters…
Assuming the newly observed structure $Z_{b}(10610)$ as a bottomonium-like molecular state $B^{*}\bar{B}$, we calculate its mass in the framework of QCD sum rules. The numerical result is $10.54\pm0.22 GeV$ for $B^{*}\bar{B}$, which…
We discuss decays and productions for the possible molecular states formed by bottom mesons B (B*) and anti-B (anti-B*). The twin resonances found by Belle, Zb(10610) and Zb(10650), are such candidates. The spin wave functions of the…
The $Z_b(10610)^\pm$ and $Z_b(10650)^\pm$ are two bottomonium-like structures discovered in the $\pi h_b(mP)$, $\pi \Upsilon(nS)$ and $B^\ast\bar B^{(\ast)}+h.c.$ invariant mass spectra, where $m=\{1,2\}$ and $n=\{1,2,3\}$. Their nature is…
The observation of two charged bottomonium-like structures $Z_b(10610)$ and $Z_b(10650)$ has stimulated extensive studies of the properties of $Z_b(10610)$ and $Z_b(10650)$. In this talk, we briefly introduce the research status of…
We study charmed and strange baryon resonances that are generated dynamically by a unitary baryon-meson coupled-channel model which incorporates heavy-quark spin symmetry. This is accomplished by extending the SU(3) Weinberg-Tomozawa chiral…
Very recently, the LHCb collaboration has reported the new result about the hidden-charm pentaquarks: $P_c(4312)$ near the $\bar{D}\Sigma_c$ threshold, and $P_c(4440)$ and $P_c(4457)$ near $\bar{D}^*\Sigma_c$ threshold. We study the heavy…
Flavor-exotic tetraquark mesons have recently been observed in the heavy-quark pair sectors of QCD, including two isospin multiplets in the b b-bar sector, Z_b(10610) and Z_b(10650), and one isospin multiplet in the c c-bar sector,…
In the framework of the one-boson-exchange model, we have studied the interaction of the $B^*\bar{B}$ and $B^*\bar{B}^{*}$ system. After considering the S-wave and D-wave mixing, we notice that both $Z_b(10610)^\pm$ and $Z_b(10650)^\pm$ can…
The spectrum of the doubly heavy baryons is estimated with respect to the new observation from the LHCb collaboration [Aaij:2017ueg] by using the chiral partner structure and heavy quark spin-flavor symmetry. The effects of heavy quark…