  Pebble accretion is an emerging paradigm for the fast growth of planetary
cores. Pebble flux and pebble sizes are the key parameters used in the pebble
accretion models. We aim to derive the pebble sizes and fluxes from
state-of-the-art dust coagulation models, understand their dependence on disk
parameters and the fragmentation threshold velocity, and the impact of those on
the planetary growth by pebble accretion. We use a one-dimensional dust
evolution model including dust growth and fragmentation to calculate realistic
pebble sizes and mass flux. We use this information to integrate the growth of
planetary embryos placed at various locations in the protoplanetary disk.
Pebble flux strongly depends on disk properties, such as its size and
turbulence level, as well as on the dust aggregates fragmentation threshold. We
find that dust fragmentation may be beneficial to planetary growth in multiple
ways. First of all, it prevents the solids from growing to very large sizes,
for which the efficiency of pebble accretion drops. What is more, small pebbles
are depleted at a slower rate, providing a long-lasting pebble flux. As the
full coagulation models are computationally expensive, we provide a simple
method of estimating pebble sizes and flux in any protoplanetary disk model
without substructure and with any fragmentation threshold velocity.
