The decay $D^0 to pi^+ pi^- pi^0$ appears to be dominated by $rho pi$ states in a configuration of zero total isotopic spin. The spin $J$, parity $P$, and charge-conjugation eigenvalue $C$ of this final state are therefore $J^{PC} = 0^{--}$, which ca
nnot be formed of a quark $q$ and antiquark $bar q$. If a resonance near $M(D^0)$ dominates the final state, it must be a {it hybrid} composed of a quark-antiquark pair and a constituent gluon, or a {it tetraquark} $q q bar q bar q$. A test for this resonance in electroproduction is proposed.
The LHCb experiment is capable of studying four-body decays of the $b$-flavored baryons $Lambda_b$ and $Xi_b^0$ to charmless final states consisting of charged pions, kaons, and baryons. We remark on the search in such modes for CP-violating triple p
roduct asymmetries and for CP rate asymmetries relative to decays involving charmed baryons.
Using 9.32, 5.88 million Upsilon(2S,3S) decays taken with the CLEO-III detector, we obtain five product branching fractions for the exclusive processes Upsilon(2S) => gamma chi_{b0,1,2}(1P) => gamma gamma Upsilon(1S) and Upsilon(3S) => gamma chi_{b1,
2}(1P) => gamma gamma Upsilon(1S). We observe the transition chi_{b0}(1P) => gamma Upsilon(1S) for the first time. Using the known branching fractions for B[Upsilon(2S) => gamma chi_{bJ}(1P)], we extract values for B[chi_{bJ}(1P) => gamma Upsilon(1S)] for J=0, 1, 2. In turn, these values can be used to unfold the Upsilon(3S) product branching fractions to obtain values for B[Upsilon(3S) => gamma chi_{b1,2}(1P) for the first time individually. Comparison of these with each other and with the branching fraction B[Upsilon(3S) => gamma chi_{b0}] previously measured by CLEO provides tests of relativistic corrections to electric dipole matrix elements.
Analyzing $Upsilon(nS)$ decays acquired with the CLEO detector operating at the CESR $e^+e^-$ collider, we measure for the first time the product branching fractions ${cal B}[Upsilon(nS)togammachi_{b}((n-1)P_J)] times {cal B}[chi_{b}(n-1)P_J)to X_i]$
for $n=2$ and 3, where $X_i$ denotes, for each $i$, one of the fourteen exclusive light-hadron final states for which we observe significant signals in both $chi_b(1P_J)$ and $chi_b(2P_J)$ decays. We also determine upper limits for the electric dipole (E1) transitions $Upsilon(3S) to gamma chi_b(1P_J)$.
