Can only flavor nonsinglet H dibaryons be stable against strong decays?
Journal
Physical Review
Journal Volume
C56
Pages
570-573
Date Issued
1997
Author(s)
Abstract
Using the QCD sum-rule approach, we show that the flavor-nonsinglet [Formula Presented] dibaryon states with [Formula Presented] (27 plet) are nearly degenerate with the [Formula Presented] singlet [Formula Presented] dibaryon, which has been predicted to be stable against strong decay, but has not been observed. Our calculation, which does not require an instanton correction, suggests that the [Formula Presented] is slightly heavier than these flavor-nonsinglet [Formula Presented]’s over a wide range of the parameter space. If the singlet [Formula Presented] mass lies above the [Formula Presented] threshold (2231 MeV), then the strong interaction breakup to [Formula Presented] would produce a very broad resonance in the [Formula Presented] invariant mass spectrum which would be very difficult to observe. On the other hand, if these flavor-nonsinglet [Formula Presented] and 1 [Formula Presented] dibaryons are also above the [Formula Presented] threshold, but below the [Formula Presented] breakup threshold (2254 MeV), then because the direct, strong interaction decay to the [Formula Presented] channel is forbidden, these flavor-nonsinglet states might be more amenable to experimental observation. The present results allow a possible reconciliation between the reported observation of [Formula Presented] hypernuclei, which argue against a stable [Formula Presented], and the possible existence of [Formula Presented] dibaryons in general. © 1997 The American Physical Society.
Type
journal article