A typical LMXB emits almost all of it's radiation in X-rays, and typically less than one percent in visible light, so they are among the brightest objects in the X-ray sky, but relatively faint in visible light. The apparent magnitude is typically around 20 magnitudes. The brightest part of the system is the accretion disk around the compact object. The orbital periods of LMXB range from a few hours to a few days.
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