#AthenaNuggets: X-IFU Filters: Soap Bubbles to Block Undesired Photons

In the #AthenaNuggets 52, Marco Barbera describes the X-IFU filters and their current status.

The X-ray Integral Field Unit (X-IFU) is sensitive to lower energy photons ( ultraviolet/visible/infrared) which, though not detected as single events, deposit energy on the absorber raising the noise. To block these low energy photons, the X-IFU will have two sets of filters: the first one named Thermal Filters (THFs) (responsibility of UNIPA and INAF-OAPA, Palermo, Italy) will be assembled inside the cryostat, and the second one named Optical Blocking Filters (OBFs) (responsibility of UNIGE, Geneva, Switzerland).