Hadronic decays involving heavy pentaquarks

Recently several experiments have reported evidence for pentaquark ${\Theta }^{+}.$ H1 experiment at HERA-B has also reported evidence for ${\Theta }_c.$ ${\Theta }^{+}$ is interpreted as a bound state of an $\overline{s}$ with four other light quarks udud which is a member of the antidecuplet of flavor ${\mathrm{SU}\left(3\right)\mathrm{}}_f,$ while ${\Theta }_c$ is a heavy state obtained with the $\overline{s}$ in ${\Theta }^{+}$ being replaced by a $\overline{c}$ which is a member of an antisixtet. A heavy pentaquark triplet can also be formed with a $\overline{c}$ and four light quarks. Similarly heavy pentaquark antisixtet and triplet can be formed with the $\overline{c}$ being replaced by a $\overline{b}.$ We study decay processes involving at least one heavy pentaquark using ${\mathrm{SU}\left(3\right)\mathrm{}}_f$ and estimate the decay widths for some decay modes. We find several relations for heavy pentaquark decays into another heavy pentaquark and a ${B(B}^{*})$ or a ${D(D}^{*})$ which can be tested in the future. The B can also decay through weak interaction to charmed heavy pentaquarks. We also study some B decay modes with a heavy pentaquark in the final states. Experiments at B factories will provide important information about the heavy pentaquark properties.