A comment on "Importance of resolving the spectral support of beam-plasma instabilities in simulations" by M. Shalaby et al

Understanding the physics of beam-plasma systems is of great importance for a large number of astrophysical systems. Recently the validity of particle-in-cell simulations of these systems has been questioned by Shalaby et al. (2017) We analyse one specific beam-plasma and its numerical simulations Kempf et al. (2016) that has been critized and prove that in fact the simulations performed fulfill the new validity criteria introduced by Shalaby et al. (2016).