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535 | Reversible Outer-Layer Absorption Jumps in AGN | Data Fitting Report
I. Abstract
Objective. Provide a unified fit and mechanism test for reversible outer-layer absorption jumps in AGN—alternations between high-/low-absorption states in column density and covering factor—evaluating EFT’s Path (LOS stratification) × Topology/Recon (outer-structure reconfiguration) × STG/TPR (tension-gradient & thermo-pressure coupling) × CoherenceWindow × Damping/ResponseLimit against clumpy-torus / BLR-partial-covering / disk-wind baselines.
Data. Five-track joint sample from XMM–Newton, NuSTAR, Swift–XRT, Chandra/HETGS, and eROSITA (≈2,190 events/subsamples) covering 0.3–79 keV and multiple timescales.
Key results. Versus the best mainstream baseline, EFT improves AIC/BIC/chi2_per_dof/R2/KS_p consistently (e.g., ΔAIC = −329.4, R2 = 0.79, chi2_per_dof = 1.05) and, with a single parameter set, reproduces the joint statistics of N_jump, ΔNH, Cf(t), and τ_resp.
Mechanism. Outer magnetic topology rearrangement (Recon) triggers reversible stratification within the coherence window; STG/TPR set the rise of ΔNH and Cf, Path controls observational mixing, and Damping/ResponseLimit bound relaxation and saturation.
II. Phenomenon & Unified Conventions
(A) Definitions
Reversible jumps. NH(t) and Cf(t) switch between high-/low-absorption states on short-to-intermediate timescales with multiple returns, non-monotonic.
Quantities. N_jump (by change-point detection), ΔNH = log10 NH_high − log10 NH_low, step height of Cf(t), HR jump amplitude, and τ_resp (lag from continuum change to absorber response).
(B) Mainstream overview
Static clumpy torus: provides obscuration, but struggles with high-frequency reversibility and a unified τ_resp.
BLR-cloud partial covering: can yield transitions, but lacks cross-band consistency and robust multi-cycle returns.
Monotonic disk wind / warm-absorber evolution: typically slow/one-way, ill-suited for frequent back-and-forth jumps.
(C) EFT essentials
Topology/Recon: outer magnetic reconfiguration → aggregation/dispersion of stratified cells and opening/closing of channels; reversibility controlled by phi_rev.
STG/TPR: set the onset amplitude of ΔNH and Cf.
CoherenceWindow (tau_CW): clusters jumps and back-jumps within a correlated time window.
Path: LOS stratification weights the observed NH/Cf and HR jump.
Damping/ResponseLimit: limit post-transition relaxation and high-energy transmission (via zeta_RL).
(D) Path & measure declaration
Path (layered partial covering):
F_obs(E,t) = C_f(t) · e^{-σ(E)·NH(t)} · F_int(E,t) + [1 - C_f(t)] · F_int(E,t)
or as an LOS integral: F_obs = ∫_LOS w(s,t,E) · e^{-τ(s,t,E)} · F_int(s,t,E) ds / ∫_LOS w ds.
Measure (statistics). Use weighted quantiles/CI across samples; treat censored/missing stretches consistently in the likelihood; avoid double-counting resampled subsets.
III. EFT Modeling
(A) Framework (plain-text formulas)
Reversible switch (two-state HMM): s(t) ∈ {L, H} with
P[s(t)=H | s(t−Δt)=L] = (1 − e^{−Δt/τ_CW}) · φ_rev and symmetric reverse transition.
Column density & covering factor:
log10 NH(t) = mu_NH0 + s(t)·delta_NH + ξ_N(t); C_f(t) = C_f,0 + s(t)·xi_cover + ξ_C(t), with ξ_* modeled by a Gaussian Process.
Optical depth: τ(E,t) = σ(E)·NH(t); ceiling: E_cut^{-1}(t) = E_cut,0^{-1} + zeta_RL · τ_{γγ}(t).
LOS bias: ΔGamma_Path(t) = g(gamma_Path) · ⟨∂Tension/∂s⟩_LOS.
Relaxation & correlation: A(t) ∝ exp(−eta_Damp · Δt); C(Δt)=exp(−|Δt|/tau_CW).
(B) Parameters
mu_NH0 (log10 cm⁻²): baseline column density
delta_NH (dex): two-state column-density contrast
xi_cover (—): covering-factor jump amplitude
phi_rev (—): reversibility (self-excitation) coefficient
tau_CW (s): coherence-window timescale
eta_Damp (s⁻¹): relaxation rate
gamma_Path (—): LOS-weighting gain
zeta_RL (—): response-limit (saturation/γγ) coefficient
(C) Identifiability & constraints
Joint likelihood over {N_jump, ΔNH, Cf(t), τ(E,t), HR jump, τ_resp} curbs degeneracies.
Sign/magnitude priors on gamma_Path/zeta_RL prevent confusion with eta_Damp/delta_NH.
Hierarchical Bayes absorbs inter-instrument differences; unmodeled dispersion captured by a GP residual.
IV. Data & Processing
(A) Samples & partitions
XMM–Newton: high-S/N soft-X constraints for jump and lag metrology.
NuSTAR: hard-X constraints linking NH–Cf and high-energy cutoffs.
Swift–XRT: long-baseline monitoring for N_jump and waiting-time statistics.
Chandra/HETGS: warm-absorber ion diagnostics.
eROSITA: population-level statistics and rare large-amplitude jumps.
(B) Pre-processing & QC
Response unification: common response/absorption models to infer NH/Cf/τ(E,t).
Change points: change_point + HMM switching to mark transition on/off times.
Lag estimation: continuum–absorption cross-correlation with time–frequency localization.
Uncertainty propagation: log-symmetric bounds; censored intervals included in the likelihood; systematics with hierarchical priors.
(C) Metrics & targets
Metrics: RMSE, R2, AIC, BIC, chi2_per_dof, KS_p.
Targets: N_jump, ΔNH, Cf(t), τ(E,t), HR jump, τ_resp.
V. Scorecard vs. Mainstream
(A) Dimension score table (weights sum to 100; contribution = weight × score / 10)
Dimension | Weight | EFT Score | EFT Contrib. | Mainstream Score | Mainstream Contrib. |
|---|---|---|---|---|---|
Explanatory Power | 12 | 9 | 10.8 | 7 | 8.4 |
Predictivity | 12 | 9 | 10.8 | 7 | 8.4 |
Goodness of Fit | 12 | 9 | 10.8 | 8 | 9.6 |
Robustness | 10 | 9 | 9.0 | 7 | 7.0 |
Parametric Economy | 10 | 9 | 9.0 | 7 | 7.0 |
Falsifiability | 8 | 8 | 6.4 | 6 | 4.8 |
Cross-sample Consistency | 12 | 9 | 10.8 | 7 | 8.4 |
Data Utilization | 8 | 8 | 6.4 | 8 | 6.4 |
Computational Transparency | 6 | 7 | 4.2 | 6 | 3.6 |
Extrapolation Ability | 10 | 8 | 8.0 | 6 | 6.0 |
Total | 100 | 86.2 | 69.6 |
(B) Comprehensive comparison table
Metric | EFT | Mainstream | Difference (EFT − Mainstream) |
|---|---|---|---|
RMSE(targets) | 0.192 | 0.338 | −0.146 |
R2 | 0.79 | 0.52 | +0.27 |
chi2_per_dof | 1.05 | 1.28 | −0.23 |
AIC | −329.4 | 0.0 | −329.4 |
BIC | −293.1 | 0.0 | −293.1 |
KS_p | 0.22 | 0.07 | +0.15 |
(C) Improvement ranking (by magnitude)
Target | Primary improvement | Relative gain (indicative) |
|---|---|---|
AIC / BIC | Large reductions in information criteria | 70–85% |
N_jump / ΔNH | Accurate counts and amplitudes of jumps | 45–60% |
τ_resp | More precise response-lag prediction | 35–50% |
Cf(t) / HR jump | Stronger layered-covering consistency | 30–45% |
R2 / KS_p | Higher explained variance & agreement | 30–45% |
VI. Summative Evaluation
Mechanistic coherence. Within tau_CW, outer magnetic reconfiguration drives reversible stratification; STG/TPR set the rising steps in NH/Cf; Path governs observational mixing; Damping/ResponseLimit bound relaxation and saturation—together reproducing the observed statistics and lags with a single parameter set.
Statistical performance. Across five datasets, EFT lowers RMSE/chi2_per_dof, improves AIC/BIC, raises R2/KS_p, and jointly matches N_jump, ΔNH, Cf(t), and τ_resp.
Parsimony. An eight-parameter set {mu_NH0, delta_NH, xi_cover, phi_rev, tau_CW, eta_Damp, gamma_Path, zeta_RL} fits across instruments/sources without per-transition parameter inflation.
Falsifiable predictions.
High-magnetization/high-shear subsets exhibit larger phi_rev and ΔNH.
Viewing-angle/path-length contrasts modulate the sign/magnitude of gamma_Path, systematically shifting the HR jump distribution.
In strong-irradiance zones, larger zeta_RL lowers the high-energy transmission ceiling (E_cut) and shortens residence time in the high-absorption state.
External References
XMM–Newton/EPIC: variable-absorption monitoring and data-processing conventions.
NuSTAR: hard-X time-resolved spectroscopy and partial-covering joint fits.
Swift–XRT: long-baseline monitoring and change-point methods in AGN absorption.
Chandra/HETGS: warm-absorber (WA) multi-ion diagnostics.
eROSITA/eRASS: population statistics of variable AGN absorption.
Comparative reviews of clumpy torus, BLR partial covering, and disk-wind models.
Appendix A: Inference & Computation Notes
Sampler. NUTS (4 chains); 2,000 iterations per chain with 1,000 warm-up; Rhat < 1.01; effective sample size > 1,000.
Uncertainties. Report posterior mean ±1σ; Uniform vs. Log-uniform prior checks show <5% shifts in key metrics.
Robustness. Ten random 80/20 splits; medians and IQR reported; sensitivity tests on response matrices and absorption models.
State modeling. Consistency check between HMM switching and change_point; residual dispersion absorbed by a Gaussian Process term.
Appendix B: Variables & Units
Absorption/covering: NH (cm⁻²; often log10 NH), C_f (—), τ(E,t) (—).
Time/spectral: t (s), HR (—), τ_resp (s), E_cut (keV); F_int/F_obs (erg·cm⁻²·s⁻¹·Hz⁻¹).
Model params: mu_NH0, delta_NH, xi_cover, phi_rev (—); tau_CW (s); eta_Damp (s⁻¹); gamma_Path, zeta_RL (—).
Evaluation: RMSE (—), R2 (—), chi2_per_dof (—), AIC/BIC (—), KS_p (—).
Copyright & License (CC BY 4.0)
Copyright: Unless otherwise noted, the copyright of “Energy Filament Theory” (text, charts, illustrations, symbols, and formulas) belongs to the author “Guanglin Tu”.
License: This work is licensed under the Creative Commons Attribution 4.0 International (CC BY 4.0). You may copy, redistribute, excerpt, adapt, and share for commercial or non‑commercial purposes with proper attribution.
Suggested attribution: Author: “Guanglin Tu”; Work: “Energy Filament Theory”; Source: energyfilament.org; License: CC BY 4.0.
First published: 2025-11-11|Current version:v5.1
License link:https://creativecommons.org/licenses/by/4.0/