Tools for simulations - Athena
Tools for simulations
Athena effective area science requirements
The Athena effective area science requirements are:
| Requirement | Energy (keV) | Instrument | Area (cm2) |
| SCI-EA-R-050 | 0.35 | X-IFU | ≥1050 |
| SCI-EA-R-060 | 1 | X-IFU | ≥10500 |
| SCI-EA-R-070 | 7 | X-IFU | ≥1600 |
| SCI-EA-R-075 | 10 | X-IFU | ≥300 |
| SCI-EA-R-081 | 0.2 | WFI | ≥690 |
| SCI-EA-R-091 | 1 | WFI | ≥12500 |
| SCI-EA-R-100 | 7 | WFI | ≥1800 |
| SCI-EA-R-110 | 10 | WFI | ≥400 |
Requirement implementation
The requirements are implemented through the following mirror configuration:
- Mirror Assembly (MA) with 15 rows, 6 sectors, 600 mirror modules
- Active mirror apertues radius 244-1256 mm
- Mirror plate rib spacing (pitch) of 2.3 mm
- 10 nm of Ir coating on each individual module, plus 4 nm SiC overcoating in rows 9 to 15 (the outermost). The SiC layer thickness has been optimised to achieve the best possible area in the 2-4 keV energy range (unpublished study by Desiree della Monica Ferreira, DTU)
- -1/+1 wedging geometry
The mirror geometry is described in the Athena Telescope Reference Document (TRD) version 3.1 by Tim Oosterbroek (ESA/ESTEC).
Component Data Files
Estimates of the on-axis effective area, vignetting curves, and Point Spread Function (PSF) have been provided by Prof. Richard Willingale (University of Leicester). The data files provided on this web page are preliminary. They have been based on realistic ray-trace experiments including all known loss effects. In addition, they do include provisional loss factors to account for expected losses such as misalignments, coating imperfections, contamination, etc. The simulations correspond to the simulated mission at beginning-of-life conditions.
Mirror Effective Area On Axis (X-ray tracing, 1 eV energy resolution)
- 15 rows, 2.3 mm rib pitch, Ir+SiC coating in the outermost MA rows (nominal baseline configuration): ASCII
For historical reasons, and for compliance with the original nominal requirements specified above, readers can download also an effective area data file corresponding to a Ir+B4C coating. For historical reason, an effective area file corresponding to a non-optimized SiC layer thickness of 10 nm is available as well.
VIGNETTING
- Peak normalized vignetting curve as a function of energy and off-axis angle: ASCII (radial profile: PDF)
ON-AXIS PSF
- Image of the on-axis 1 keV PSF for the nominal HEW requirement (5"): FITS (pixel size=0.1")
- Image of the on-axis 1 keV PSF for a moderately degraded HEW (6.5"): FITS (pixel size=0.1")
- Image of the on-axis 1 keV PSF for an extremely degraded HEW (7"): PDF (pixel size=0.1")
ON-AXIS De-focused PSF
Images (FITS) and radial profiles (ASCII) of the 35-mm de-focused PSF as a function of energy (pixel size=0.25") at :
OFF-AXIS AREAs and PSF
- Area, HEW, and paramaters describing the PSF as a function of energy and off-axis angles for the nominal on-axis HEW requirement (5"): ASCII (radial dependence of the HEW: EPS)
- Area, HEW, and parameters describing the PSF as a function of energy and off-axis angles for a moderately degraded on-axis HEW (6.5"): ASCII (radial dependence of the HEW: EPS)
- Area, HEW, and parameters describing the PSF as a function of energy and off-axis angles for an extremely degraded on-axis HEW (7"): ASCII (radial dependence of the HEW: EPS)
The PSF model is a 2-D distribution whose radial profile corresponds to a modified pseudo-Voigt distribution.
X-ray stray light
This tarfile contains software (C procedure) and associated data files to produce stray light estimates for three possible wedging schemes: +1/-1, 0/-2. +2/0. They will be shortly integrated in SIXTE.