You are studying a mystery companion to an evolved star, with mass transfer happening. Which of the following properties suggests that the companion is definitely a black hole?

Question

Quizplus · Accepted Answer

The property that suggests that the companion is definitely a black hole is that it has a mass of over 3 solar masses. This is because any object with a mass greater than 3 solar masses is too massive to be a neutron star, which is the only other compact object that could potentially be the companion in this scenario. Therefore, a mass greater than 3 solar masses strongly suggests that the companion is a black hole. The other properties listed (X-ray emitting accretion disk and periodic X-ray bursts) are both consistent with mass transfer in a binary system, but they do not necessarily indicate that the companion is a black hole.

You Are Studying a Mystery Companion to an Evolved Star