  For decades, the spectral variations of Beta Pictoris have been modelled as
the result of the evaporation of exocomets close to the star, termed falling
evaporating bodies (FEBs). Resonant perturbations by a giant planet have been
proposed to explain the dynamical origin of these stargrazers. The disk is now
known to harbour two giant planets, Beta Pic b and c, orbiting the star at 9.9
au and 2.7 au. While the former almost matches the planet formerly suspected,
the discovery of the latter complicates the picture. We first question the
stability of the two-planet system. Then we investigate the dynamics of a disk
of planetesimals orbiting the star with both planets to check the validity of
the FEB generation mechanism. Symplectic N-body simulations are used to
determine which regions of the planetesimal disk are dynamically stable. Then
we focus on regions where disk particles are able to reach high eccentricities
thanks to resonant mechanisms. The first result is that the system is
dynamically stable. Both planets may temporarily fall in 7:1 mean motion
resonance (MMR). Then, simulations reveal that the whole region extending
between ~1.5 au and ~25 au is unstable to planetary perturbations. However, a
disk below 1.5 au survives, which appears to constitute an active source of
FEBs via high-order MMRs with Beta Pic c. Beta Pic b acts as a distant
perturber that helps sustain the whole process. These simulations rule out the
preceding FEB generation mechanism model, which placed their origin at around
4-5 au. Conversely, FEBs are likely to originate from a region much further in
and related to MMRs with Beta Pic c. That mechanism also appears to last
longer, as new planetesimals are able to continuously enter the MMRs and evolve
towards the FEB state. Subsequently, the physical nature of the FEBs may differ
from that previously thought, and presumably may not be icy.
