Simultaneous Broadband Observations of jet-dominated active galaxies with NuSTAR

The exceptionally energetic particle populations at work within powerful relativistic jets associated with active galaxies make these sources natural targets for the NuSTAR hard X-ray instrument. This space-based satellite can observe their emission between 3 and 70 keV with unprecedented sensitivity. This emission is likely due to the synchrotron process, and particles responsible for the hard X-ray emission are also expected to produce gamma-rays via inverse Compton process observed by instruments such as Fermi Large Area Telescope, VERITAS, MAGIC and HESS. Since the launch of NuSTAR, the instrument has led simultaneous broadband campaigns on multiple gamma-ray emitting jetted active galaxies. NuSTAR was able to observe Mrk 421 during unprecedented low and high states, as well as variability in Mrk 501 consistent with a magnetic reconnection event. Additionally, the extreme blazar 1ES 0229+200 was observed with NuSTAR, together with ground based gamma-ray instruments, providing the first complete picture of the broadband emission. These invaluable observations of BL Lac-type objects were supplemented with NuSTAR observations of the exceptionally variable flat spectrum radio quasar 3C 279, observed during the highest gamma-ray state yet observed by the Fermi LAT instrument. We will share the results from these multiwavelength campaigns, with particular emphasis on the implications for the study of the most relativistic particle populations at work within the Universe.