X-ray Hardness

Convolved/Predicted ACIS-S hardness plot

Hardness ratios calculated from the predicted ACIS-S Aimpoint spectra of selected X-Atlas targets (× = hot star; ◊ = cool star). S, M, and H are the total predicted counts in the passbands listed on the plot. Sigma Ori in Obsid 3738 is circled in red on the plot.
Download plot: GIF PS
Download plot data: Text file
View complete listing of X-Atlas Spectral Metrics (Hardness, Quantiles).


Convolved/Predicted ACIS-I hardness plot

Hardness ratios calculated from the predicted ACIS-I Aimpoint spectra of selected X-Atlas targets (× = hot star; ◊ = cool star). S, M, and H are the total predicted counts in the passbands listed on the plot. Sigma Ori in Obsid 3738 is circled in red on the plot.
Download plot: GIF PS
Download plot data: Text file
View complete listing of X-Atlas Spectral Metrics (Hardness, Quantiles).


Hardness Ratios for Sigma Ori, Obsid 3738
Aimpoint HR1 = (H-M)/(H+M) HR2 = (M-S)/(M+S) HR3 = (H-S)/(H+S)
ACIS-S -0.838 -0.535 -0.948
ACIS-I -0.808 -0.329 -0.898

X-ray Quantiles

Convolved/Predicted ACIS-S Aimpoint Quantile gridACIS-S hot stars JPG Postscript Convolved/Predicted ACIS-S Aimpoint Quantile gridACIS-S cool stars JPG Postscript
Convolved/Predicted ACIS-I Aimpoint Quantile gridACIS-I hot stars JPG Postscript Convolved/Predicted ACIS-I Aimpoint Quantile gridACIS-I cool stars JPG Postscript
Quantile-based color-color diagram: (m = Q50 = (E50 - Elo)/(Ehi - Elo)). Elo = 0.3 keV; Ehi = 8.0 keV
View complete listing of X-Atlas Spectral Metrics (Hardness, Quantiles).

Quantiles for Sigma Ori, Obsid 3738
Aimpoint Quantiles 25 % 25 % Error 50 % 50 % Error 75 % 75 % Error
ACIS-S keV 0.635 0.000 0.767 0.000 0.898 0.006
Q-norm 0.044 0.000 0.061 0.000 0.078 0.001
ACIS-I keV 0.708 0.000 0.840 0.007 0.971 0.007
Q-norm 0.053 0.000 0.070 0.001 0.087 0.001

Observation Preview Chandra Configuration for the Observation
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