At the left, the ATHENA space observatory with the unfolded solar panels. The primary mirror of the telescope is located upfront. The two focal plane instruments are located at the opposite. The overall height of the spacecraft is about 15 meters, derived from the 12 meter focal length of the telescope. Credits: X-IFU Consortium. Copyrights: ©DB/X-IFU At the right, conceptual design of the primary mirror structure: Left, mirror assembly and accommodation. Insert right, mirror modules and stacks. Credit ESA, Cosine and ACO Team.
Cerdanyola del Vallès, 18 June 2021. Synchrotron light facilities are powerful research infrastructures at the service of a great variety of scientific disciplines. It is well-known that the bright beams of synchrotron light are very helpful to determine the structure and properties of matter and also as a powerful tool for X-ray optics metrology of instruments able to study our universe.
The ALBA Synchrotron and the European Space Agency started a collaboration in 2020 to build a new beamline at the Spanish facility for helping in the development of the ATHENA mission, aimed to become the largest X-ray observatory ever built.
The ATHENA X-ray telescope will be launched in the early thirties to map hot gas structures, determine their physical properties, and search for supermassive black holes. It will offer spatially-resolved X-ray spectroscopy and deep wide-field X-ray spectral imaging representing a step forward from the current operating X-ray astronomy satellites.
One of the key elements of this telescope is the innovative modular architecture of its optics. The main optical element is the primary mirror of the telescope made of 15 concentric rings and filed by more than 600 mirror modules based on the Silicon Pore Optics (SPO) technology. Each of these mirror modules are organized in a set of stacks of highly polished silicon wafer reflecting plates. The figure and alignment of these stacks are crucial to achieve the required angular resolution of the telescope.
The beamline being built at ALBA, called MINERVA (name given to the Greek goddess Athena by the Romans), will provide a test platform during the assembly and characterization of the many mirror modules before they are integrated into the telescope. "The layout of the beamline will reproduce the same optical conditions in which each mirror module will be subjected once integrated in the spatial telescope. More precisely, the beamline emulates the optical path taken by X-rays photons from their emission by cosmic objects, their focusing by the mirror module and finally their transport to the detector", says Dominique Heinis, beamline leader of MINERVA at ALBA.
MINERVA will team up with the Dutch company cosine measurement systems and with the PTB (German National Metrology Institute), which operates the XPBF 2.0 beamline at the BESSY II Synchrotron (Berlin, Germany), a beamline designed and operated to test and calibrate X-ray mirror modules. Their beamline design is also the base of MINERVA's. cosine manufactures the mirror modules for the ATHENA X-ray telescope, and will be the main user of the MINERVA beamline. "For the MINERVA development, we count with the valuable collaboration of the stakeholders of the project. The design and construction of the beamline is the responsibility of ALBA that is benefiting from experiences collected at BESSY II and from the user perspective given by Cosine and the European Space Agency", says Carles Colldelram, project manager of MINERVA at the ALBA Synchrotron.
The beamline project started on the 12th of March 2020 and the final beamline design is already completed with the goal of being in operation in 2022. MINERVA is co-funded by the European Space Agency (ESA) and the Spanish Ministry of Science and Innovation.
"We are very proud of contributing to this ambitious project that will unveil new secrets about our universe. Synchrotron facilities are very sophisticated tools at the service of cutting-edge science", says Caterina Biscari, director of the ALBA Synchrotron.
Area of the ALBA experimental hall where MINERVA beamline will be placed.
