Chandra ACIS-S3 Spectra of NGC 6543

The images show the regions used to extract source and background spectra:
• White regions define the sources.
• White regions with red strikes are excluded.
• Red regions define the background areas whose spectrum was subtracted to the source spectrum.

The spectra and calibration files used in this analysis can be downloaded from here in a 12.2 MB tar file.
• The X-ray fluxes are derived from the spectral models with the best statistical fit.

Source and background regions used for the nebular spectrum.

MODEL: PHABS × VMEKAL

Nebular abundances with N and Ne allowed to vary.

Reduced χ² = χ²/DoF = 32.44/29 = 1.12

kT = 0.146 keV
N_H = 4.0×10²⁰ cm⁻²

N = 1.4×N_neb
Ne = 1.6×Ne_neb

Absorbed flux:
f^abs (0.25−2.5 keV) = 1.0×10⁻¹³ ergs cm⁻² s⁻¹
f^abs (0.45−2.5 keV) = 6.2×10⁻¹⁴ ergs cm⁻² s⁻¹
Unabsorbed flux:
F_X (0.25−2.5 keV) = 1.8×10⁻¹³ ergs cm⁻² s⁻¹
F_X (0.45−2.5 keV) = 8.2×10⁻¹⁴ ergs cm⁻² s⁻¹
Luminosity:
L_X (0.25−2.5 keV) = 2.2×10³¹ ergs s⁻¹
L_X (0.45−2.5 keV) = 1.0×10³¹ ergs s⁻¹

MODEL: PHABS × VMEKAL

Nebular abundances.

Reduced χ² = χ²/DoF = 38.53/30 = 1.28

kT = 0.145 keV
N_H = 4.0×10²⁰ cm⁻²

Source and background regions used for the stellar spectrum.

MODEL: PHABS × VMEKAL

Nebular abundances with Ne allowed to vary.

Reduced χ² = χ²/DoF = 10.22/11 = 0.93

kT = 0.166 keV
N_H = 4×10²⁰ cm⁻²

Ne = 6.3×Ne_neb

Absorbed flux:
f^abs (0.25−2.5 keV) = 7.6×10⁻¹⁵ ergs cm⁻² s⁻¹
f^abs (0.45−2.5 keV) = 5.5×10⁻¹⁵ ergs cm⁻² s⁻¹
Unabsorbed flux:
F_X (0.25−2.5 keV) = 1.2×10⁻¹⁴ ergs cm⁻² s⁻¹
F_X (0.45−2.5 keV) = 7.1×10⁻¹⁵ ergs cm⁻² s⁻¹
Luminosity:
L_X (0.25−2.5 keV) = 1.5×10³⁰ ergs s⁻¹
L_X (0.45−2.5 keV) = 8.6×10²⁹ ergs s⁻¹

MODEL: PHABS × ( MEKAL + MEKAL )

Two thermal plasma emission models with Nebular abundances.

Reduced χ² = χ²/DoF = 5.13/12 = 0.43

kT₁ = 0.15 keV
kT₂ = 0.8 keV
N_H fixed to 4×10²⁰ cm⁻²