  In the context of plasma wakefield acceleration beam driven, we exploit a
high density charge trailing bunch whose self-fields act by mitigating the
energy spread increase via beam loading compensation, together with bunch
self-contain operated by the self-consistent transverse field. The work, that
will be experimentally tested in the SPARC_LAB test facility, consists of a
parametric scan that allows to find optimized parameters in order to preserve
the high quality of the trailing bunch over the entire centimeters acceleration
length, with a final energy spread increase of 0.1% and an emittance increase
of 5 nm. The stability of trailing bunch parameters after acceleration is
tested employing a systematic scan of the parameters of the bunches at the
injection. The results show that the energy spread increase keeps lower than 1%
and the emittance increase is lower than 0.02 mm mrad in all the simulations
performed. The energy jitter is of the order of 5%.
