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Anisotropy of the X-ray luminosity-temperature relation of galaxy clusters
Lorenzo Lovisari (INAF - OAS)
Tuesday 26/05/2020 @ 14:00, Google Hangouts Meet
The isotropy of the Universe is a fundamental pillar of the standard model of cosmology. However, in the last decade, several studies have reported deviations from isotropy when using various cosmological probes. Therefore, new and independent methods to robustly test this fundamental assumption are of crucial importance. In Migkas et al. (2020) we presented a novel method that makes use of the tight correlation between the X-ray luminosity (Lx) and the temperature (T) of galaxy clusters. We detected a region that seems to share a significantly different Lx-T relation than the rest of the sky. Many X-ray and cluster related reasons that could potentially explain this anisotropy were tested, but none was able to fully explain the tension. Considering how this effect would bias all galaxy clusters studies with X-ray data, it is crucial to identify the exact nature of this behaviour. In the talk I will present our analysis and present possible explanations for our findings.
Link to the recorded talk: https://youtu.be/OXZ290YFxVY