The Universe’s First Jet Propulsion Laboratories: Radio and X-ray Jets from Reionization-Era Quasars

Quasars seen in the first billion years of the Universe (z ≥ 5.6) are extremely important lampposts providing views into the early cosmos. Yet, as more is learned about these objects, more questions arise — chiefly, how did such massive objects form so quickly? Radio-loud quasars could potentially provide important context for these questions, but, until recently, very few were known at such high redshifts. When these objects are discovered, they become excellent targets for X-ray observations, as, owing to how the energy density of the CMB scales as (1+z)⁴, inverse Compton interactions with CMB photons make X-rays a fundamental tracer of jets at this epoch. In this talk, I will discuss recent work on mapping out the properties of jets at high redshifts, both in the radio and in X-rays; in particular, I will discuss X-ray observations of two quasars: the most radio-powerful non-blazar quasar known in the high-z Universe and the most distant radio-loud quasar yet seen. The detection of X-ray emission with and without radio counterparts near these objects offers vital insights into how jets have shaped the growth and evolution of the earliest supermassive black holes and their surroundings. Finally, I will briefly introduce a recently approved Chandra large program to systematically study the full population of high-redshift radio-loud quasars and their potential jets.