Opening the path to hard X-/soft Gamma-ray focussing: The ASTENA-pathfinder mission.

Ferro L., Moita M., Rosati P., Frontera F., Guidorzi C., Lolli R., Guidi V., Mazzolari A., Bandiera L., Virgilli E., Caroli E., Stephen J. B., Auricchio N., Amati L., Orlandini M., Labanti C., Campana R., Ferrari C., Del Sordo S., Massa E., Mana G., Sasso C. P.
  Lunedì 12/09   14:00 - 19:00   Aula T - Caterina Scarpellini   III - Astrofisica   Presentazione
Hard X-/soft Gamma-ray astronomy is a key field for transient, nuclear and multimessenger astrophysics. However, the spatial localization, imaging capabilities and sensitivity of the measurements are strongly limited for the energy range $>$ 70 ${keV}$. To overcome these limitations, we have proposed a mission concept, ASTENA, submitted to ESA for its program "Voyage 2050". We will report on a pathfinder of ASTENA, that we intend to propose to ASI as an Italian mission with international participation. It will be based on one of the two instruments aboard ASTENA: a Laue lens with $20 {m}$ focal length, able to focus hard X-rays in the $50\mbox{--}700 {keV}$ passband. It makes use of bent crystals that diffract gamma-ray photons in transmission configuration. A 3D position-sensitive spectro-imager detector will be positioned on the lens focus. The combination of the focussing properties of the lens and of the localization properties of the detector will provide unparalleled imaging and spectroscopic capabilities, thus enabling studies of phenomena such as Gamma-ray bursts afterglows, supernova explosions, positron annihilation lines and many more.