X-ray Hardness and Quantiles

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. Canopus in Obsid 636 is circled in red on the 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. Canopus in Obsid 636 is circled in red on the plot.

Hardness Ratios for Canopus, Obsid 636
Aimpoint	HR₁ = (H-M)/(H+M)	HR₂ = (M-S)/(M+S)	HR₃ = (H-S)/(H+S)
ACIS-S	-0.724	-0.077	-0.758
ACIS-I	-0.687	0.105	-0.627

X-ray Quantiles

Quantile-based color-color diagram: (m = Q₅₀ = (E₅₀ - E_lo)/(E_hi - E_lo)). E_lo = 0.3 keV; E_hi = 8.0 keV

View complete listing of X-Atlas Spectral Metrics (Hardness, Quantiles).

Quantiles for Canopus, Obsid 636

Aimpoint Quantiles 25 % 25 % Error 50 % 50 % Error 75 % 75 % Error
ACIS-S keV 0.767 0.007 0.898 0.007 1.059 0.004

Q-norm 0.061 0.001 0.078 0.001 0.099 0.001
ACIS-I keV 0.825 0.000 0.956 0.000 1.146 0.006

Q-norm 0.068 0.000 0.085 0.000 0.110 0.001

Observation Preview

Chandra Configuration for the Observation

Return to Search Page

X-Atlas Home

ACIS-S hot stars JPG Postscript	ACIS-S cool stars JPG Postscript
ACIS-I hot stars JPG Postscript	ACIS-I cool stars JPG Postscript

Quantiles for Canopus, Obsid 636
Aimpoint	Quantiles	25 %	25 % Error	50 %	50 % Error	75 %	75 % Error
ACIS-S	keV	0.767	0.007	0.898	0.007	1.059	0.004
ACIS-S	Q-norm	0.061	0.001	0.078	0.001	0.099	0.001
ACIS-I	keV	0.825	0.000	0.956	0.000	1.146	0.006
ACIS-I	Q-norm	0.068	0.000	0.085	0.000	0.110	0.001