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. Theta-1 Ori E in Obsid 2568 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. Theta-1 Ori E in Obsid 2568 is circled in red on the plot.

Hardness Ratios for Theta-1 Ori E, Obsid 2568
Aimpoint	HR₁ = (H-M)/(H+M)	HR₂ = (M-S)/(M+S)	HR₃ = (H-S)/(H+S)
ACIS-S	-0.172	0.466	0.320
ACIS-I	-0.116	0.611	0.534

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 Theta-1 Ori E, Obsid 2568

Aimpoint Quantiles 25 % 25 % Error 50 % 50 % Error 75 % 75 % Error
ACIS-S keV 0.986 0.003 1.263 0.005 1.745 0.011

Q-norm 0.089 0.000 0.125 0.001 0.188 0.001
ACIS-I keV 1.044 0.007 1.351 0.007 1.818 0.011

Q-norm 0.097 0.001 0.136 0.001 0.197 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 Theta-1 Ori E, Obsid 2568
Aimpoint	Quantiles	25 %	25 % Error	50 %	50 % Error	75 %	75 % Error
ACIS-S	keV	0.986	0.003	1.263	0.005	1.745	0.011
ACIS-S	Q-norm	0.089	0.000	0.125	0.001	0.188	0.001
ACIS-I	keV	1.044	0.007	1.351	0.007	1.818	0.011
ACIS-I	Q-norm	0.097	0.001	0.136	0.001	0.197	0.001