Related papers: Pentaquark Decay in QCD Sum Rules
In this article, we tentatively assign the $P_c(4312)$ to be the $\bar{D}\Sigma_c$ pentaquark molecular state with the spin-parity $J^P={\frac{1}{2}}^-$, and discuss the factorizable and non-factorizable contributions in the two-point QCD…
The QCD sum rule for the pentaquark $\Theta^+$, first analyzed by Sugiyama, Doi and Oka, is reanalyzed with a phenomenological side that explicitly includes the contribution from the two-particle reducible kaon-nucleon intermediate state.…
Assuming that the recently observed $\Theta^+$ and $\Xi^{--}$ are members of an anti-decuplet of SU(3), decays to ground state baryons and mesons are calculated using an effective Lagrangian which incorporates chiral and SU(3) symmetry. We…
In this work, we extend our previous work on the $D^*\bar{D}^*$ molecular states with the $J^{PC}=0^{++}$, $1^{+-}$ and $2^{++}$ to investigate their two-body strong decays via the QCD sum rules based on rigorous quark-hadron duality. We…
We demonstrate that a five quark state of positive parity with an internal P-wave structure - usually pictured as a composite of an antiquark and two diquarks in a P-wave state - can couple to nucleons and Goldstone particles in a chirally…
We introduce a relative P-wave to construct the vector doubly-charm diquark $(\widetilde{V})$, therefore, the scalar and tensor four-quark currents to investigate the decay widths of the fully-charm tetraquark states with the…
A systematic lowering in mass of strangeness ambiguous $pK^0_S$ peaks relative to the $nK^+$ is noted. We discuss how measurement of $\gamma p\to \Theta^+ K^0_S\to p K^0_S K^0_S \to p\pi^+\pi^-\pi^+\pi^-$ in association with $\gamma p\to…
A general study of pentaquarks built with four quarks in a L=1 state and an antiquark in S-wave shows that several of such states are forbidden by a selection rule, which holds in the limit of flavour symmetry, to decay into a baryon and a…
We study properties of the pentaquark particle Theta+ with emphasis on the role of chiral symmetry. It is shown that when chiral force is sufficiently strong, the positive parity Theta+ may be realized with a lower mass relative to the…
The recently observed pentaquark baryons $\Theta^{+}$ and $\Xi^{--}$ are studied in the dual gravity theory of QCD. By developing a general formulation useful for studying the branched string web in a curved space, simple mass formulae of…
We analyse the top-quark decay at the next-to-next-to-leading order (NNLO) in QCD by using the Principle of Maximum Conformality (PMC) which provides a systematic way to eliminate renormalization scheme and scale ambiguities in perturbative…
We study pentaquark $\Theta^{+} (I=0,J=1/2)$ in the QCD sum rules emphasizing that we can not extract any properties of the pentaquark outside of the Borel window. To find the appropriate Borel window, we prepare a favorable set up of the…
It is pointed out that the previously suggested interpretation of the hidden-charm pentaquarks $P_c(4312)$, $P_c(4440)$ and $P_c(4457)$ as molecular bound states of $\Sigma_c \bar D$ and $\Sigma_c \bar D^*$ baryon-meson pairs gives rise to…
We study the narrow decay width of low-lying penta-quark baryons in the QCD string theoryin terms of gluonic excitations. In the QCD string theory, the penta-quark baryon decays via a gluonic-excited state of a baryon and meson system,…
We give sum rules for tetraquark decay coupling constants, taking into account the SU(3) symmetry breaking interactions to first order.
Based on SU(3) flavor symmetry, we decompose the decay amplitudes of bottom baryon decays to a pseudoscalar meson and an octet (a decuplet) pentaquark in terms of three (two) invariant amplitudes $T_1$ and $T_{2,3}$ ($\tilde T_1$ and…
We investigate the production of the pentaquark $\Theta^+$ baryon via the $\gamma n\to K^-\Theta^+$ and $\gamma p\to \bar{K}^0 \Theta^+$ processes, focusing on the parity of the $\Theta^+$. Using the effective Lagrangians, we calculate the…
We review the current status of the exotic pentaquark baryons. After a brief look at experiments of both positive and negative results, we discuss theoretical methods to study the structure and reactions for the pentaquarks. First we…
The experimental signature of an S=+1 baryon of mass 1540 MeV and width 10-25 MeV has led to speculation that this is an exotic baryon consisting of 4 quarks and 1 antiquark lying at the top of a $\bar{10}$ SU(3) multiplet. The observed…
A sum rule relating the widths of the decays of mesons belonging to heavy quark multiplets, having the same parity and light quark spin j, into the low lying $0^-$ and $1^-$ multiplet is obtained. As this sum rule follows from properties of…