Defocussing of the Athena optics is now a requirement and can be considered in evaluating the count rate performance of the X-IFU. Defocussing spreads the source counts over a large number of pixels (1000). Each pixel can sustain a count rate of the order of 40-50 cps. A Crab like source would produce about 90 000 cps over the full TES array. Therefore it is obvious that with defocussing, the X-IFU is capable of observing bright point sources.

Broad band (0.2-12 keV) high resolution and total throughputs

High throughput for mid and high resolution events (spectral resolution less than 10 eV) is certainly required around the Iron like between 5 and 8 keV. The use of Be filters would remove a large fraction of the soft photons and therefore reduce the overall count rate of point sources while preserving the interesting events above 5 keV. The X-IFU can achieve throughputs as high as 70% with maximum defocussing and the use of Be filter. The above number will reduce (by a few 10% at 1 Crab) if events affected by cross talk are removed.

The high+mid resolution event fraction in the 5-8 keV band.

The figures shown above are courtesy of Philippe Peille (December 2016), on behalf of the end-to-end simulator team.

Overview papers

• The Athena X-ray Integral Field Unit - D. Barret et al.
• X-IFU technical challenge - Th. Lam Trong

Instrument oriented papers

• The focal plane assembly for the Athena X-ray Integral Field Unit instrument - B. Jackson et al.
• Transition-edge sensor pixel parameter design of the microcalorimeter array for the x-ray integral field unit on Athena-r (B&W version available)- S. J. Smith et al.
• Preliminary thermal architecture of the X-IFU instrument dewar - I. Charles et al.
• Development of frequency domain multiplexing for the X-ray Integral Field unit (X-IFU) on the Athena - H. Akamatsu et al.
• Optimising the multiplex factor of the frequency domain multiplexed readout of the TES-based microcalorimeter imaging array for the X-IFU instrument on the Athena x-ray observatory - van der Kuur et al.
• Gain drift compensation with no-feedback-loop developed for the X-IFU:ATHENA readout chain - D. Prêle et al.
• Conceptual design of the X-IFU Instrument Control Unit on board the ESA Athena mission - L. Corcione et al.
• The filter wheel and filters development for the X-IFU instruments onboard Athena - E. Bozzo et al.
• Surface investigation and aluminum oxide estimation on test filters for the ATHENA X-IFU and WFI detectors - L. Sciortino et al.
• Temperature effects on the performances of the ATHENA X-IFU thermal filters - M. Barbera et al.

• Updates on the background estimates for the X-IFU instrument onboard of the ATHENA mission - S. Lotti et al.
• The Cryogenic Anti-Coincidence detector for ATHENA X-IFU pulse analysis of the AC-S7 single pixel prototype - M. D'Andrea et al.
• The Cryogenic AntiCoincidence detector for ATHENA X-IFU-a program overview - C. Macculi et al.
• The mechanical and EM simulations of the CryoAC for the ATHENA X-IFU - D. Corsini et al.
• The new cryogenic silicon monolithic micro-bridged Anticoincidence detector for the X-IFU of ATHENA - M. Biasotti et al.

End-to-end simulation oriented papers

• TESSIM a simulator for the Athena-X-IFU - J. Wilms et al.
• Performance assessment of different pulse reconstruction algorithms for the ATHENA X-ray Integral Field Unit - Ph. Peille et al.
• Microcalorimeter pulse analysis by means of principle component decomposition - C.P. de Vries et al.
• The impact of crosstalk in the X-IFU instrument on Athena science cases - R. den Hartog et al.
• Observing the WHIM with Athena - T. Brand et al.

- The Athena mission proposal

- The Hot and Energetic Universe White Paper

- The X-ray Integral Field Unit (X-IFU) - Preliminary description

- X-IFU master presentations in zipped keynote and zipped PDF

• The X-ray Integral Field Unit (X-IFU) for Athena - Ravera et al.
  and the accompanying talk can be downloaded here
• The DRE, the digital readout electronics for Athena X-IFU - Ravera et al.
• The Cryogenic AntiCoincidence detector for Athena: the progress towards the final pixel design - Macculi et al.
• Background simulations for the Athena X-IFU instrument: impact on the instrumental design - Lotti et al.
• Requirements for the detectors and read-out of Athena X-IFU - Den Hartog et al.
• Towards Mo/Au based TES detectors for Athena/X-IFU - Fabrega et al.
• Baseline design of the thermal blocking filters for the X-IFU detector on board ATHENA - Barbera et al.
• Athena end-to-end simulations - Wilms et al.