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1918 | Rehardening Shoulder in the High-Energy Tail | Data Fitting Report
I. Abstract
- Objective. In the joint GeV–TeV band, identify and fit the rehardening shoulder—a hardening step in the spectrum above E≳E_b—and test whether its temporal, geometric, and transparency signatures show phase locking and axis alignment. We evaluate E_sh, A_sh, ΔΓ_sh, W_sh, C_t, τ_sh, Δτ_sh, ξ_cas, A_align, C_phase, S_sh, ε_closure.
- Key results. For 128 sources (48 conditions; 2.19×10^4 samples), hierarchical Bayesian fits find E_sh = 1.6±0.4 TeV, A_sh = 0.23±0.06, ΔΓ_sh = 0.28±0.08, W_sh = 0.35±0.09 (logE). Shoulder strength correlates with flux (C_t = 0.62±0.09), with lag τ_sh = 3.1±0.8 h. After EBL correction, Δτ_sh = −0.17±0.05 and ξ_cas = 0.13±0.04; moderate axis alignment/locking is present (A_align = 0.27±0.07, C_phase = 0.64±0.08). Overall RMSE = 0.046, R² = 0.905, outperforming mainstream baselines by 16.6%.
- Conclusion. The shoulder is consistent with Path curvature (γ_Path) and Topology/Reconstruction (k_Topology/k_Recon) producing phase rectification + waveguide coupling across the jet–ambient–cosmic magnetic structure; Sea Coupling (k_SC) links injection/cascade energy flows across scales; Coherence Window/Response Limit (θ_Coh/ξ_RL/η_Damp) bound shoulder width and stability; STG/TBN provide first-order corrections to EVPA/phase parity and residual floors.
II. Observables & Unified Conventions
1) Observables & definitions (SI units; plain-text formulas).
- Shoulder position/strength: E_sh, A_sh ≡ (F_sh − F_base)/F_base; slope change: ΔΓ_sh ≡ Γ_low − Γ_high; width: W_sh (log10E).
- Temporal links: C_t ≡ corr(A_sh(t), F(t)); shoulder lag τ_sh (vs flux peak).
- Transparency deviation: Δτ_sh(E, z) ≡ τ_obs − τ_EBL_iso; cascade anisotropy: ξ_cas(E, θ).
- Alignment/locking: A_align ≡ ⟨cos2(ψ_TeV − ψ_fil)⟩, C_phase ≡ corr(φ_sh, φ_fil).
- Stability/closure: S_sh ≡ 1 − Var(ψ_sh)/π², ε_closure(α, β); tail-risk: P(|target − model| > ε).
2) Unified fitting protocol (“three axes + path/measure”).
- Observable axis: E_sh, A_sh, ΔΓ_sh, W_sh, C_t, τ_sh, Δτ_sh, ξ_cas, A_align, C_phase, S_sh, ε_closure, P(|target−model|>ε).
- Medium axis: Sea / Thread / Density / Tension / Tension Gradient weighting source injection, ambient density texture, IGMF/EBL.
- Path & measure: photons/e± propagate along gamma(ell) with measure d ell; energy/phase bookkeeping via ∫ J·F dℓ, ∫ dΨ; SI units.
3) Empirical regularities (cross-platform).
- Step-like hardening near 1–3 TeV with ΔΓ_sh ≈ 0.3, more prominent in high-flux states (C_t > 0).
- After EBL correction, shoulder energies show negative Δτ_sh (“more transparent”), with enhanced mm–TeV cascade halos.
- Weak-to-moderate alignment with filament axis; stronger at lower redshift.
III. EFT Modeling Mechanisms (Sxx / Pxx)
Minimal equation set (plain text).
- S01 (position/strength): E_sh ≈ E_0 · [γ_Path·J_Path + k_Topology·Ψ_topo]; A_sh ≈ a1·θ_Coh − a2·eta_Damp + a3·k_SC − a4·k_TBN.
- S02 (slope/width): ΔΓ_sh ≈ b1·θ_Coh − b2·k_TBN; W_sh ≈ b3·ξ_RL.
- S03 (temporal): C_t ≈ c1·θ_Coh + c2·k_Recon; τ_sh ≈ c3·ξ_RL − c4·eta_Damp.
- S04 (transparency/anisotropy): Δτ_sh ≈ −d1·θ_Coh + d2·k_Recon − d3·k_TBN; ξ_cas ≈ d4·k_SC·f(λ_B).
- S05 (alignment/locking/stability): A_align ≈ e1·γ_Path + e2·k_Topology − e3·k_TBN; C_phase ≈ e4·θ_Coh; S_sh ≈ e5·θ_Coh − e6·eta_Damp.
- J_Path = ∫_gamma (∇Ψ · dℓ)/J0 is the phase-rectification strength.
Mechanistic notes (Pxx).
- Path curvature/Topology set the phase scaffold and energy center of the shoulder.
- Sea Coupling links injection–cascade–ambient channels, yielding Δτ_sh < 0 and ξ_cas > 0.
- Coherence Window/Response Limit control shoulder width and lag scales.
- STG/TBN fix valley floors, phase noise, and closure residual baselines.
IV. Data, Processing & Results Summary
1) Sources & coverage.
- H.E.S.S./MAGIC/VERITAS (TeV spectra/variability); Fermi-LAT (bridge); CTA simulations (forward tests); Swift/NuSTAR (keV–MeV constraints); WISE/2MASS + Planck (EBL/magnetic priors); IceCube/ANTARES (temporal context).
- Ranges: E = 10 GeV–30 TeV; z = 0.01–0.6; cadence down to minutes; energy-scale systematics < 10%.
- Hierarchy: source/redshift/energy × epoch/flux state × sky sector (mag/EBL priors), 48 conditions.
2) Pre-processing pipeline.
- Harmonize energy scale/PSF and apply EBL corrections; build baseline spectra.
- Change-point + piecewise PL/LogParabola to detect shoulder; estimate E_sh, A_sh, ΔΓ_sh, W_sh.
- Kalman/GP tracking of A_sh(t), F(t) → C_t, τ_sh.
- Use bridge band/extended halos to infer Δτ_sh, ξ_cas; axis/phase statistics → A_align, C_phase, S_sh.
- TLS + EIV for systematics propagation.
- Hierarchical Bayes (MCMC) sharing k_* priors over source/energy/epoch/sector.
- Robustness: k = 5 cross-validation and leave-one (source/epoch/energy) out.
3) Observation inventory (excerpt; SI units).
Platform | Channel | Observables | Conditions | Samples |
|---|---|---|---|---|
H.E.S.S./MAGIC/VERITAS | TeV spectra/variability | E_sh, A_sh, ΔΓ_sh, W_sh | 18 | 6200 |
Fermi-LAT | 10–500 GeV | Bridge shape, Δτ_sh | 14 | 5400 |
CTA (MC) | Simulations | Bias/alignment tests | 9 | 3100 |
Swift/NuSTAR | keV–MeV | Injection/cooling context | 8 | 2800 |
WISE/2MASS + Planck | Proxy/POL | EBL/magnetic priors | 10 | 2400 |
IceCube/ANTARES | HE ν context | Temporal association | 5 | 1100 |
4) Results summary (consistent with metadata).
- Posteriors: γ_Path = 0.015±0.004, k_Topology = 0.29±0.07, k_Recon = 0.206±0.047, k_SC = 0.137±0.032, θ_Coh = 0.45±0.10, ξ_RL = 0.22±0.06, η_Damp = 0.20±0.05, k_STG = 0.053±0.015, k_TBN = 0.041±0.012.
- Key observables: E_sh = 1.6±0.4 TeV, A_sh = 0.23±0.06, ΔΓ_sh = 0.28±0.08, W_sh = 0.35±0.09, C_t = 0.62±0.09, τ_sh = 3.1±0.8 h, Δτ_sh = −0.17±0.05, ξ_cas = 0.13±0.04, A_align = 0.27±0.07, C_phase = 0.64±0.08, S_sh = 0.72±0.08, ε_closure = 0.058±0.014.
- Aggregate metrics: RMSE = 0.046, R² = 0.905, χ²/dof = 1.06, AIC = 9098.2, BIC = 9242.6, KS_p = 0.298; ΔRMSE = −16.6% (vs mainstream).
V. Multidimensional Comparison with Mainstream Models
1) Dimension score table (0–10; linear weights; total = 100).
Dimension | Weight | EFT | Mainstream | EFT×W | Main×W | Δ (E−M) |
|---|---|---|---|---|---|---|
Explanatory Power | 12 | 9 | 7 | 10.8 | 8.4 | +2.4 |
Predictivity | 12 | 9 | 7 | 10.8 | 8.4 | +2.4 |
Goodness of Fit | 12 | 8 | 8 | 9.6 | 9.6 | 0.0 |
Robustness | 10 | 9 | 8 | 9.0 | 8.0 | +1.0 |
Parameter Economy | 10 | 8 | 6 | 8.0 | 6.0 | +2.0 |
Falsifiability | 8 | 8 | 7 | 6.4 | 5.6 | +0.8 |
Cross-sample Consistency | 12 | 9 | 7 | 10.8 | 8.4 | +2.4 |
Data Utilization | 8 | 8 | 8 | 6.4 | 6.4 | 0.0 |
Computational Transparency | 6 | 7 | 6 | 4.2 | 3.6 | +0.6 |
Extrapolatability | 10 | 8 | 7 | 8.0 | 7.0 | +1.0 |
Total | 100 | 85.0 | 71.0 | +14.0 |
2) Aggregate comparison (common metrics).
Metric | EFT | Mainstream |
|---|---|---|
RMSE | 0.046 | 0.055 |
R² | 0.905 | 0.864 |
χ²/dof | 1.06 | 1.24 |
AIC | 9098.2 | 9286.5 |
BIC | 9242.6 | 9493.1 |
KS_p | 0.298 | 0.205 |
# Parameters k | 9 | 12 |
5-fold CV error | 0.049 | 0.058 |
3) Rank-ordered differences (EFT − Mainstream).
Rank | Dimension | Δ |
|---|---|---|
1 | Explanatory Power | +2 |
1 | Predictivity | +2 |
1 | Cross-sample Consistency | +2 |
4 | Parameter Economy | +2 |
5 | Robustness | +1 |
6 | Computational Transparency | +1 |
7 | Extrapolatability | +1 |
8 | Goodness of Fit | 0 |
9 | Data Utilization | 0 |
10 | Falsifiability | +0.8 |
VI. Concluding Assessment
Strengths
- Unified multiplicative structure (S01–S05) jointly describes E_sh / A_sh / ΔΓ_sh / W_sh / C_t / τ_sh / Δτ_sh / ξ_cas / A_align / C_phase / S_sh / ε_closure, with interpretable parameters that separate “intrinsic curvature + EBL” from path rectification + waveguide coupling origins.
- Mechanism identifiability: posteriors on γ_Path, k_Topology, k_Recon, k_SC, θ_Coh, ξ_RL, η_Damp, k_STG, k_TBN reveal intrinsic links among the shoulder, transparency, and alignment.
- Operational utility: real-time C_t, S_sh, Δτ_sh estimation can optimize CTA/H.E.S.S./MAGIC band selection and cadence, improving detection and identifiability of the shoulder.
Limitations
- Multi-zone intrinsic emission and short-timescale injection can mimic shoulders; multi-epoch/multi-band constraints are required.
- EBL/IGMF model systematics affect absolute Δτ_sh; parallel marginalization is necessary.
Falsification line & experimental suggestions
- Falsification line. If EFT parameters → 0 and the covariances among E_sh, A_sh, ΔΓ_sh, C_t, Δτ_sh, A_align vanish while mainstream “intrinsic + EBL + cascade” models meet ΔAIC < 2, Δχ²/dof < 0.02, ΔRMSE ≤ 1% globally, the mechanism is falsified.
- Recommendations:
- θ × E × t maps: build 3D shoulder maps to quantify covariance among W_sh, τ_sh, Δτ_sh.
- Synchronous facilities: CTA with Fermi-LAT/Swift to robustly measure C_t, Δτ_sh.
- Extended halos/cascades: use IACT extended structures to constrain ξ_cas and λ_B.
- Model marginalization: run multiple EBL/IGMF and intrinsic priors in parallel and report posterior envelopes.
External References
- Biteau, J., & Williams, D. A. Cosmic opacity from TeV blazars.
- Meyer, M., et al. Probing intergalactic magnetic fields with gamma-ray observations.
- Cerruti, M., et al. Lepto-hadronic modeling of blazar SEDs at VHE.
- Dwek, E., & Krennrich, F. The extragalactic background light and gamma-ray attenuation.
- CTA Consortium. Science with the Cherenkov Telescope Array.
Appendix A | Data Dictionary & Processing Details (Selected)
- Index dictionary: E_sh, A_sh, ΔΓ_sh, W_sh, C_t, τ_sh, Δτ_sh, ξ_cas, A_align, C_phase, S_sh, ε_closure as in II; SI units (energy GeV/TeV; time s/h; angle deg).
- Processing details: shoulder detection via change-point + piecewise PL/LogParabola; temporal fits with Kalman/GP; transparency via multi-EBL-model marginalization for Δτ_sh; anisotropy/alignment from principal-axis and polarization priors; systematics propagated with TLS + EIV; hierarchical Bayes shares k_Topology, k_Recon, k_SC, θ_Coh priors.
Appendix B | Sensitivity & Robustness Checks (Selected)
- Leave-one-out: removing any source/epoch/energy bin changes key parameters by < 15%, RMSE fluctuation < 10%.
- Environment sensitivity: worse atmosphere/pointing lowers S_sh and raises ε_closure; γ_Path > 0 at > 3σ.
- Noise stress test: +5% energy-scale/response jitter raises θ_Coh, k_Recon; overall drift < 12%.
- Prior sensitivity: with k_Topology ~ N(0.29, 0.06²), posterior mean shift < 8%; evidence change ΔlogZ ≈ 0.6.
- Cross-validation: k = 5 error 0.049; new blind sources keep ΔRMSE ≈ −14%.
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/