The images here compare the real HETG observed spectral images with Event-2D-synthesized images.
The real data images are made from 6 merged images: the plus and minus orders for the 3 epochs. Because of the different rolls and signs of the orders the individual spectral images are also rotated, but because of E0102's bright ring they generally overlap to produce a pretty clean ~ circular line image.
The model images use the observed zeroth-order image and combine this with
the IACHEC spectral model without the "Fe" lines
included* to synthesize the expected dispersed images for the
6 data sets (3 epochs, 2 orders). These are then combined just as the data
images were to produce the model image.
[* The "Fe" lines in the model are at wavelengths: 32.40, 17.09, 17.05, 16.77,
15.26, 15.01, 14.58, 14.20, 13.51, 12.82, 11.73, 10.61, 8.66 A.]
The residual images show the difference between the data and model images with a color coding that indicates the significance and sign of the difference: Red means the data are 2-sigma or more greater than the model; blue indicates that the data are 2-sigma or more less than the model. Yellow and Green indicate differences less than 2-sigma significance.
The very obvious red residual regions show the extra flux (above the model) due to "Fe" lines in the data. There are 4 main regions of excess (in the MEG range shown): perhaps a line at 10.61 (between Mg and Ne), broad emission around 12.82 (between the Ne X and Ne IX images), extended residuals longward of Ne IX (14.20--14.58--15.01--15.26), and perhaps a line just longward of O Ly beta[16A] at 17.05--17.10.
| 8.0 A | 19.5 A |
| Model no "Fe" |
| MEG Data |
| MEG Residuals |
| HEG Residuals |
| HEG Data |
| Model no "Fe" |
| 8.0 A | 16.5 A |