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arXiv · 2502.10866

The X-ray Integral Field Unit at the end of the Athena reformulation phase

Philippe Peille·Didier Barret·Edoardo Cucchetti·Vincent Albouys·Luigi Piro·Aurora Simionescu·Massimo Cappi·Elise Bellouard·Céline Cénac-Morthé·Christophe Daniel·Alice Pradines·Alexis Finoguenov·Richard Kelley·J. Miguel Mas-Hesse·Stéphane Paltani·Gregor Rauw·Agata Rozanska·Jiri Svoboda·Joern Wilms·Marc Audard·Enrico Bozzo·Elisa Costantini·Mauro Dadina·Thomas Dauser·Anne Decourchelle·Jan-Willem den Herder·Andrea Goldwurm·Peter Jonker·Alex Markowitz·Mariano Mendez·Giovanni Miniutti·Silvano Molendi·Fabrizio Nicastro·François Pajot·Etienne Pointecouteau·Gabriel W. Pratt·Joop Schaye·Jacco Vink·Natalie Webb·Simon Bandler·Marco Barbera·Maria Teresa Ceballos·Ivan Charles·Roland den Hartog·W. Bertrand Doriese·Jean-Marc Duval·Flavio Gatti·Brian Jackson·Caroline Kilbourne·Claudio Macculi·Sylvain Martin·Yann Parot·Frederick Porter·Damien Prêle·Laurent Ravera·Stephen Smith·Jan Soucek·Tanguy Thibert·Eija Tuominen·Fabio Acero·Stefano Ettori·Nicolas Grosso·Jelle Kaastra·Pasquale Mazzotta·Jon Miller·Salvatore Sciortino·Sophie Beaumont·Matteo D'Andrea·Jelle de Plaa·Megan Eckart·Luciano Gottardi·Maurice Leutenegger·Simone Lotti·Alexei Molin·Lorenzo Natalucci·Muhammad Qazi Adil·Andrea Argan·Elisabetta Cavazzuti·Mauro Fiorini·Pourya Khosropanah·Eduardo Medinaceli Villegas·Gabriele Minervini·James Perry·Frederic Pinsard·Desi Raulin·Manuela Rigano·Peter Roelfsema·Denis Schwander·Santiago Terron·Guido Torrioli·Joel Ullom·Monika Zuchniak·Laurence Chaoul·Jose Miguel Torrejon·Frank Brachet·Beatriz Cobo·Malcolm Durkin·Valentina Fioretti·Hervé Geoffray·Lionel Jacques
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Abstract

The Athena mission entered a redefinition phase in July 2022, driven by the imperative to reduce the mission cost at completion for the European Space Agency below an acceptable target, while maintaining the flagship nature of its science return. This notably called for a complete redesign of the X-ray Integral Field Unit (X-IFU) cryogenic architecture towards a simpler active cooling chain. Passive cooling via successive radiative panels at spacecraft level is now used to provide a 50 K thermal environment to an X-IFU owned cryostat. 4.5 K cooling is achieved via a single remote active cryocooler unit, while a multi-stage Adiabatic Demagnetization Refrigerator ensures heat lift down to the 50 mK required by the detectors. Amidst these changes, the core concept of the readout chain remains robust, employing Transition Edge Sensor microcalorimeters and a SQUID-based Time-Division Multiplexing scheme. Noteworthy is the introduction of a slower pixel. This enables an increase in the multiplexing factor (from 34 to 48) without compromising the instrument energy resolution, hence keeping significant system margins to the new 4 eV resolution requirement. This allows reducing the number of channels by more than a factor two, and thus the resource demands on the system, while keeping a 4' field of view (compared to 5' before). In this article, we will give an overview of this new architecture, before detailing its anticipated performances. Finally, we will present the new X-IFU schedule, with its short term focus on demonstration activities towards a mission adoption in early 2027.

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Philippe Peille, Didier Barret, Edoardo Cucchetti, Vincent Albouys, Luigi Piro, Aurora Simionescu, Massimo Cappi, Elise Bellouard, Céline Cénac-Morthé, Christophe Daniel, Alice Pradines, Alexis Finoguenov, Richard Kelley, J. Miguel Mas-Hesse, Stéphane Paltani, Gregor Rauw, Agata Rozanska, Jiri Svoboda, Joern Wilms, Marc Audard, Enrico Bozzo, Elisa Costantini, Mauro Dadina, Thomas Dauser, Anne Decourchelle, Jan-Willem den Herder, Andrea Goldwurm, Peter Jonker, Alex Markowitz, Mariano Mendez, Giovanni Miniutti, Silvano Molendi, Fabrizio Nicastro, François Pajot, Etienne Pointecouteau, Gabriel W. Pratt, Joop Schaye, Jacco Vink, Natalie Webb, Simon Bandler, Marco Barbera, Maria Teresa Ceballos, Ivan Charles, Roland den Hartog, W. Bertrand Doriese, Jean-Marc Duval, Flavio Gatti, Brian Jackson, Caroline Kilbourne, Claudio Macculi, Sylvain Martin, Yann Parot, Frederick Porter, Damien Prêle, Laurent Ravera, Stephen Smith, Jan Soucek, Tanguy Thibert, Eija Tuominen, Fabio Acero, Stefano Ettori, Nicolas Grosso, Jelle Kaastra, Pasquale Mazzotta, Jon Miller, Salvatore Sciortino, Sophie Beaumont, Matteo D'Andrea, Jelle de Plaa, Megan Eckart, Luciano Gottardi, Maurice Leutenegger, Simone Lotti, Alexei Molin, Lorenzo Natalucci, Muhammad Qazi Adil, Andrea Argan, Elisabetta Cavazzuti, Mauro Fiorini, Pourya Khosropanah, Eduardo Medinaceli Villegas, Gabriele Minervini, James Perry, Frederic Pinsard, Desi Raulin, Manuela Rigano, Peter Roelfsema, Denis Schwander, Santiago Terron, Guido Torrioli, Joel Ullom, Monika Zuchniak, Laurence Chaoul, Jose Miguel Torrejon, Frank Brachet, Beatriz Cobo, Malcolm Durkin, Valentina Fioretti, Hervé Geoffray, Lionel Jacques. 2025-02-15. The X-ray Integral Field Unit at the end of the Athena reformulation phase. https://arxiv.org/abs/2502.10866

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