Ruben Farinelli (INAF Bologna, Italy)  — July 3, 2023

With the launch of the IXPE satellite on Decembre 9 2021, polarimetry in the X-ray band has finally regained the spotlight. Some results were theoretically expected, other ones proved to be challenging. In this seminar, I make a review of the IXPE results for a particular class of sources, X-ray binaries hosting a weakly magnetized neutron star. These systems are fundamental laboratories of General Relativity and their importance is sometimes underrated by the general public compared to that of the most exotic black holes. But they are fascinating as well, and through X-ray polarimetry for the first time we are able to catch physical and geometrical properties of these sources in a way which was difficult with spectral or temporal analysis. Finally, the recent news that the mission has been extended by 20 months provide the opportunity for students and researchers to still work for a while on this important scientific topic.