X-ray emission from Warm-Hot Intergalactic Medium

At the current epoch, approximately a half of the baryonic matter budget of the Universe is contributed by the Warm-Hot Intergalactic Medium. Being extremely tenuous and highly ionised, this matter is very difficult to observe and stays only poorly studied. Researchers at MPA have shown how it can be explored using X-ray line emission from heavier elements as a tracer. Due to scattering of the cosmic X-ray background, emission of this matter in resonant lines can be boosted strongly and become accessible for the upcoming X-ray missions