A new constraints separation for the original D=10 massless   superparticle
  We study the problem of covariant separation between first and second class constraints for the $D=10$ Brink-Schwarz superparticle. Opposite to the supersymmetric light-cone frame separation, we show here that there is a Lorentz covariant way to identify the second class constraints such that, however, supersymmetry is broken. Consequences for the $D=10$ superstring are briefly discussed. 
D. Dalmazi