The legacy of the IXPE instrument and prospects for the next generation of polarimetric photoelectric X-ray detectors

Hemanth Manikantan; Vladislavs Plesanovs; Paolo Soffitta; Dennis Sauerland; Reinhard Beck; Enrico Costa; Ettore Del Monte; Klaus Desch; Alessandro Di Marco; Sergio Fabiani; Riccardo Ferrazzoli; Markus Gruber; Saba Imtiaz; Jochen Kaminski; Alessandro Lacerenza; Fabio Muleri; Ajay Ratheesh; Alda Rubinia

arXiv · 2509.02498

The legacy of the IXPE instrument and prospects for the next generation of polarimetric photoelectric X-ray detectors

Hemanth Manikantan·Vladislavs Plesanovs·Paolo Soffitta·Dennis Sauerland·Reinhard Beck·Enrico Costa·Ettore Del Monte·Klaus Desch·Alessandro Di Marco·Sergio Fabiani·Riccardo Ferrazzoli·Markus Gruber·Saba Imtiaz·Jochen Kaminski·Alessandro Lacerenza·Fabio Muleri·Ajay Ratheesh·Alda Rubinia

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Abstract

Imaging X-ray polarimetry with IXPE has demonstrated the scientific potential of the technique but also revealed the need for significant detector upgrades, particularly with the read-out ASIC that images photoelectron tracks and possibly the multiplication stage. Building on this experience, we are developing a next generation three-dimensional photoelectron track polarimeter based on the GridPix detector, originally developed for axion and axion-like-particle searches. We report on the current status of prototype development and preparations for the ion-irradiation tests. Preliminary proton beam irradiation runs at the Bonn Isochronous Cyclotron facility of the University of Bonn verified both this generation of ASIC's tolerance to high radiation doses present in space and the capability of the cyclotron facility to operate at sufficiently low rates for controlled tests.

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Hemanth Manikantan, Vladislavs Plesanovs, Paolo Soffitta, Dennis Sauerland, Reinhard Beck, Enrico Costa, Ettore Del Monte, Klaus Desch, Alessandro Di Marco, Sergio Fabiani, Riccardo Ferrazzoli, Markus Gruber, Saba Imtiaz, Jochen Kaminski, Alessandro Lacerenza, Fabio Muleri, Ajay Ratheesh, Alda Rubinia. 2025-09-02. The legacy of the IXPE instrument and prospects for the next generation of polarimetric photoelectric X-ray detectors. https://arxiv.org/abs/2509.02498

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