Related papers: Tetraquark interpretation of $e^+ e^- \to \Upsilon…
We study the decay behaviors of the fully-bottom tetraquark states within the diquark-antidiquark picture, and calculate their relative branching ratios through the Fierz rearrangement. Our results suggest that the $C=+$ states can be…
I report recent results on hidden charm spectroscopy from Belle. These include: observation of a near-threshold enhancement in the omega-J/psi invariant mass distribution for exclusive B-->K omega J/psi decays; evidence for the decay…
Background: A resonance has been observed by the ANDY Collaboration at the Relativistic Heavy-Ion Collider at Brookhaven National Laboratory in Cu+Au collisions at center-of-mass energy $\sqrt{s} = 200$ GeV and at forward rapidity with an…
Motivated by the LHCb observation of exotic states $X_{0,1}(2900)$ with four open quark flavors in the $D^- K^+$ invariant mass distribution in the decay channel $B^\pm \to D^+ D^- K^\pm$, we study the spectrum and decay properties of the…
Diquarks are found to have the right degrees of freedom to describe the tetraquark poles in hidden-charm to open-charm meson-meson amplitudes. Compact tetraquarks result as intermediate states in non-planar diagrams of the 1/N expansion and…
We report searches for $B^0\to\rm{invisible}$ and $B^0\to\rm{invisible}+\gamma$ decays, where the energy of the photon is required to be larger than 0.5 GeV. These results are obtained from a $711\,{\rm fb}^{-1}$ data sample that contains…
Inspired by the recent observation of $\chi_{c0}(3930)$, $X(4685)$ and $X(4630)$ by the LHCb Collaboration and some exotic resonances such as $X(4350)$, $X(4500)$, etc. by several experiment collaborations, the $cs\bar{c}\bar{s}$ tetraquark…
The processes $e^{+}e^{-} \to \Delta^{++}\bar{\Delta}^{--}$ and $e^{+}e^{-}\to \Delta^{++} \bar{p} \pi^{-} + c.c.$ are studied for the first time with $179~{\rm pb}^{-1}$ of $e^{+}e^{-}$ annihilation data collected with the BESIII detector…
In a recent paper by N. Santowsky et al. [Phys. Rev. D 102, 056014 (2020)], covariant coupled equations were derived to describe a tetraquark in terms of a mix of four-quark states $2q 2\bar{q}$ and two-quark states $q\bar{q}$. These…
Recently a novel hadronic state of mass 6.9 GeV, that decays mainly to a pair of charmonia, was observed in LHCb. The data also reveals a broader structure centered around 6490 MeV and suggests another unconfirmed resonance centered at…
We present the first observation of the bottomonium ground state eta_b(1S) in the photon energy spectrum using a sample of 109+/-1 million of Upsilon(3S) events recorded at the Upsilon(3S) energy with the BaBar detector at the PEP-II B…
We search for the strange pentaquark $\Theta^+$ using kaon interactions in the material of the Belle detector. No signal is observed in the $p K_S$ final state, while in the $p K^-$ final state we observe $\sim 1.6 \cdot 10^4$…
The spectroscopic parameters and decay channels of the axial-vector tetraquark $T_{bb;\overline{u}\overline{s}}^{-}$ (in what follows, $T_{b: \overline{s}}^{\mathrm{AV}}$) are explored using the quantum chromodynamics (QCD) sum rule method.…
The recently observed Y(4260) lies far above the decay threshold with a width less than 100 MeV. We argue that it's very difficult to accommodate Y(4260) as a conventional $c\bar c$ radial excitation or a D-wave state. It can't be a…
We report improved measurements of branching fractions for B -> K pi and B -> pi pi decays based on a data sample of 449 million B Bbar pairs collected at the Upsilon(4S) resonance with the Belle detector at the KEKB e^+e^- collider. We…
We present a measurement of the top quark pair production cross section in ppbar collisions at sqrt(s)=1.96 TeV using 318 pb^{-1} of data collected with the Collider Detector at Fermilab. We select ttbar decays into the final states e nu +…
The $b \rightarrow s \gamma$, $b \rightarrow d \gamma$ and $b \rightarrow s \ell^+ \ell^-$ processes are allowed at higher order via the electroweak loop or box diagrams in the Standard model. It is sensitive probe to search for new physics…
We have analyzed 121.4 fb$^{-1}$ of data collected at the $\Upsilon(5S)$ resonance by the Belle experiment using the KEKB asymmetric-energy $e^+e^-$ collider to search for the decay $B_s^0\to J/\psi\pi^0$. We observe no signal and report an…
We report the first measurement of the inclusive $e^+e^- \to b\bar{b} \to D_s^{\pm}X$ and $e^+e^- \to b\bar{b} \to D^0/\bar{D}^0X$ cross sections in the energy range from $10.63$ to $11.02$. Based on these results, we determine $\sigma(e^+…
We report the results of a search for the $B \to Y(4260) K, ~Y(4260)\to J/\psi\pi^+\pi^-$ decays. This study is based on a data sample corresponding to an integrated luminosity of 711~fb$^{-1}$, collected at the $\Upsilon(4S)$ resonance…