The use of ultrashort laser pulses to investigate the response of materials
on femtosecond time-scales enables detailed tracking of charge, spin and
lattice degrees of freedom. When pushing the limits of the experimental
resolution, connection to theoretical modeling becomes increasingly important
in order to infer causality relations. Weyl-semimetals is particular class of
materials of recent focus due to the topological protection of the Weyl-nodes,
resulting in a number of fundamentally interesting phenomena. In this work, we
provide a first-principles framework based on time-dependent density-functional
theory for tracking the distribution of Weyl-nodes in the Brillouin-zone
following an excitation by a laser pulse. For the material TaAs, we show that
residual shifts in the Weyl-Nodes' position and energy distribution is induced
by a photo-excitation within femto-seconds, even when the laser-frequency is
off-resonant with the Weyl-node. Further, we provide information about the
relaxation pathway of the photoexcited bands through lattice vibrations