The Ninth Wide Field Imager Consortium Meeting
By Arne Rau (Athena/WFI Project Scientist)
The 9th WFI Consortium Meeting was held from March 26th to 28th at the Max Planck Institute for extraterrestrial Physics in Garching, Germany. This was the first meeting after the official endorsement of the WFI Consortium by ESA at the end of 2018 and focused mainly on the activities performed following the successful Instrument Preliminary Requirements Review in November 2018. WFI is now in Phase B1 (Preliminary Definition) and the instrument development continues full steam ahead towards the next milestone, the Mission Formulation Review in autumn 2019.
The Consortium Meeting was attended by ~90 members from nearly all 23 Consortium Partner Institutes, as well as representatives from ESA and DLR. It started with a series of splinter sessions, dedicated to the filters and filter wheel assembly and the detector electronics, and instrument control electronics. Simultaneously, the WFI Science Team assembled to review and discuss the ongoing science assessment activities.
Over the next two days, the plenary session provided details of the status of the mission, the WFI instrument, and all of its subsystems.
Continued testing of the proto-type DEPFET sensors together with their front-end electronics has demonstrated excellent spectroscopic performance and confirmed the feasibility of operation in window mode. The team now eagerly awaits the end of the pre-flight DEPFET sensor production at the Semiconductor Laboratory of the Max Planck Society, which includes full scale 512x512 devices. The first devices are expected to be available in early summer 2019 and tests will start immediately thereafter.
The filter and filter wheel developments are progressing steadily and acoustic noise tests at AGH Krakow are scheduled for later this year. To further improve the stress resistance of the large optical blocking filter under static and dynamic loads a new honeycomb mesh structure was introduced. A positive side effect of this mesh is a smaller surface and thus a further improvement in transmission at all energies.
The plenary session showed progress also of the electronics development as well as an update on the end-to-end simulator by the SIXTE team. A report on the sensitivity analysis and in particular the impact on the multi-tiered WFI survey was given by J. Aird. Additional presentations by TWG co-hair R. Willingale and X-IFU instrument scientist F. Pajot provided updates on the Athena optics and X-IFU development, respectively. The conclusion was formed by a ~1d workshop dedicated to the instrumental background, addressing the challenges associated with achieving the awaited performance.
The next consortium meeting will be hosted by the Observatoire Astronomique Strasbourg, France, in October 2019.
