  Our first result states that the orthogonal and symplectic Bessel processes
are rigid in the sense of Ghosh and Peres. Our argument in the Bessel case
proceeds by an estimate of the variance of additive statistics in the spirit of
Ghosh and Peres. Second, a sufficient condition for number rigidity of
stationary Pfaffian processes, relying on the Kolmogorov criterion for
interpolation of stationary processes and applicable, in particular, to
pfaffian sine-processes, is given in terms of the asymptotics of the spectral
measure for additive statistics.
