The High Energy X-ray Probe (HEX-P)

The High-Energy X-ray Probe (HEX-P) is a probe-class (\textasciitilde {\$}500M) next-generation high-energy X-ray observatory with broadband (2-200 keV) response and \textasciitilde 40 times the sensitivity of any previous mis-sion in the 10-80 keV band, and \textgreater 500 times the sensitivity of any previous mission in the 80-200 keV band. Intended to launch contemporaneously with Athena, HEX-P will provide fundamental new discoveries that range from resolving \textasciitilde 90{\%} of the X-ray background at its peak, to measuring the cosmic evolution of black hole spin, to studying faint X-ray populations in nearby galaxies. Based on NuSTAR heritage, HEX-P requires only modest technology development, and could easily be executed within the next decade.