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. Theta-1 Ori C in Obsid 4 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. Theta-1 Ori C in Obsid 4 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 Theta-1 Ori C, Obsid 4
Aimpoint HR1 = (H-M)/(H+M) HR2 = (M-S)/(M+S) HR3 = (H-S)/(H+S)
ACIS-S 0.023 0.492 0.509
ACIS-I 0.064 0.631 0.668

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 Theta-1 Ori C, Obsid 4
Aimpoint Quantiles 25 % 25 % Error 50 % 50 % Error 75 % 75 % Error
ACIS-S keV 1.044 0.003 1.394 0.007 1.964 0.007
Q-norm 0.097 0.000 0.142 0.001 0.216 0.001
ACIS-I keV 1.102 0.001 1.482 0.007 2.037 0.008
Q-norm 0.104 0.000 0.153 0.001 0.226 0.001

Observation Preview Chandra Configuration for the Observation
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