How do X-ray binary stars produce such powerful X-ray emissions?

X-ray binary stars produce powerful X-ray emissions through the process of accretion, where a compact object—either a neutron star or a black hole—pulls gas from a companion star.123

As this material falls toward the compact object, it cannot fall in a straight line due to its angular momentum, causing it to swirl into an accretion disk around the object. Within this disk, viscous processes and turbulence generate intense friction, which converts the orbital energy of the gas into extreme heat.14

When the gas reaches temperatures of several million kelvins, it emits copious amounts of X-rays. In some systems, this gas may also form a hot, low-density corona that contributes to high-energy X-ray output. Because the gravitational potential energy released during this process is highly efficient, these binary systems can produce X-ray outputs 1,000 times greater than the total energy emitted by the Sun across all wavelengths.412