The FORCE mission : Science aim and instrument parameter for broadband X-ray imaging spectroscopy with good angular resolution

TL;DR

FORCE is a small, high-sensitivity X-ray observatory designed for broadband imaging spectroscopy from 1 to 80 keV, aiming to explore black hole populations and complement soft X-ray missions.

Contribution

It proposes a novel small mission with unprecedented sensitivity and angular resolution for wide-band X-ray imaging, targeting new scientific fields like missing black holes.

Findings

Achieves a sensitivity of 3×10⁻¹⁵ erg cm⁻² s⁻¹ keV⁻¹ in 1 Ms exposure.

Provides 15 arcsecond angular resolution over a broad 1-80 keV band.

Enhances the capability to detect and study faint X-ray sources and black hole populations.

Abstract

FORCE is a 1.2 tonnes small mission dedicated for wide-band fine-imaging x-ray observation. It covers from 1 to 80 keV with a good angular resolution of $15"$ half-power-diameter. It is proposed to be launched around mid-2020s and designed to reach a limiting sensitivity as good as $F_X (10-40~{\rm keV}) = 3 \times 10^{-15}$~erg cm$^{-2}$ s$^{-1}$ keV$^{-1}$ within 1~Ms. This number is one order of magnitude better than current best one. With its high-sensitivity wide-band coverage, FORCE will probe the new science field of "missing BHs", searching for families of black holes of which populations and evolutions are not well known. Other point-source and diffuse-source sciences are also considered. FORCE will also provide the "hard x-ray coverage" to forthcoming large soft x-ray observatories.