  We compute the chiral critical exponents for the chiral transition in
frustrated two- and three-component spin systems with noncollinear order, such
as stacked triangular antiferromagnets (STA). For this purpose, we calculate
and analyze the six-loop field-theoretical expansion of the
renormalization-group function associated with the chiral operator. The results
are in satisfactory agreement with those obtained in the recent experiment on
the XY STA CsMnBr_3 reported by V. P. Plakhty et al., Phys. Rev. Lett. 85, 3942
(2000), providing further support for the continuous nature of the chiral
transition.
