M31 elliptical-annulus profile overview

A single place to browse the completed radial inspection, pure-data band-flux, saved-session soft-band fit-quality, and no-background terminal fit-parameter profiles. The statistical meaning of each section differs, and the sections cannot substitute for one another.

1. XSherpa inspect / data profiles

This is a pure-inspection coaxial spectral-shape comparison: one annulus per color graded from inner to outer, with all ObsID×MOS1/MOS2 kept independent — no coadd, stack, model, or fit. The y-axis is ARF-unfolded sb_flux (counts s⁻¹ keV⁻¹ cm⁻² arcmin⁻²). This section is not a radial-point profile, so no radial x/y error bars are defined; the energy axis and spectral shapes are for inspection only.

Coaxial inspect: 16′ annuli only

Coaxial inspect: preferential 8′ inner annuli

2. Direct-data band-flux profiles

Pure data, no physical model. Each faint point is one independent ObsID×MOS spectrum; the dark points and solid line are the inverse-variance average over the same region. Horizontal error bars are the exact annulus half-widths; vertical error bars are the propagated statistical errors multiplied by the max(1, sqrt(χ²/dof)) Birge factor to record the extra inter-spectrum dispersion. Units are counts s−1 cm−2 arcmin−2; the left/right panels of each figure show the non-overlapping 16′ bins and the preferential 8′ inner bins, respectively.

Direct-data band flux: 0.5–0.6 keV

Direct-data band flux: 0.6–0.7 keV

Direct-data band flux: 0.7–1.0 keV

3. 0.4–1.4 keV fit-quality (saved terminal sessions)

This is a quality metric, not a new band-only fit: all saved MOS datasets belonging to each joint fit are included, accumulating χ²=Σ(Δχ²) (χ² Gehrels) only over saved grouped bins that fall entirely within 0.4–1.4 keV. χ²/Nbin is the exact ratio over the selected bins; the approximate reduced χ² in the last column subtracts the full 0.4–7.2 keV free-parameter count and is for comparison only — it must not be read as the reduced χ² of a band-only refit. This table carries no x/y error bars.

4. Current complete 8′ no-background fit-parameter profile

This is the current authoritative complete 8′ elliptical-annulus no-background profile, superseding the previous 7-point parameter figure on this page. The 9 radial points are a016_024, a024_032, a032_040, a040_048, a048_056, a064_072, a072_080, a080_088, a088_096。

a056_064 is excluded by an explicit quality decision. Ring_v7 is a non-radial spatial region, handled only as a separate non-radial fit, so it is not included in this elliptical semi-major-axis profile.

Complete 8′ profile (2-column)

Download PDF

Complete 8′ profile (1-column)

Download PDF

Public data summary:sanitized complete-8arcmin profile manifest. It contains no raw spectra, responses, saved-session files, session hashes, or local paths.

Selection and exclusion boundaries

• a056_064 is excluded by an explicit quality decision and therefore does not enter the complete 8′ parameter profile in section 4; it is still retained in the existing inspection, band-flux, and the section-3 quality table.
• Ring_v7 was only fit as a non-radial point, so it is not used as an elliptical-annulus radial profile point.
• a096_112 and a112_128 both have outer radii larger than 100′ and do not enter the post-fit profiles in sections 3/4; a080_096 is retained (outer edge=96′).
• a128_144 has no accepted fit and is therefore not listed in the post-fit tables. All existing terminal results remain individually viewable in the complete annulus fit catalog.

Public data summary:sanitized profile manifest. It contains no absolute paths, raw/response data, saved-session files, or session hashes.