Consider an X-ray binary system in which a compact object, surrounded by an accretion disk, is in a binary orbit with another star. All of the following statements about such accretion disks are true except:
A) X-rays are emitted by the hot gas in the accretion disk.
B) The accretion disk consists of material that spills off the companion star.
C) The compact object may be either a neutron star or a black hole.
D) Several examples of flattened accretion disks being "fed" by a large companion star can be seen clearly in photos from the Hubble Space Telescope.
E) The radiation from an accretion disk may vary rapidly in time.

Question

Quizplus · Accepted Answer

The statement about flattened accretion disks being "fed" by a large companion star that can be seen clearly in photos from the Hubble Space Telescope is not true. Accretion disks are formed from material that is pulled from the companion star by the gravitational force of the compact object. While the Hubble Space Telescope has observed accretion disks in X-ray binary systems, it does not have the resolution to capture individual stars feeding the disks.

Consider an X-Ray Binary System in Which a Compact Object