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1895 | Shear Threshold Uplift in Bar–Ring Transition Zones | Data Fitting Report
I. Abstract
- Objective: In barred galaxies, quantify the critical shear threshold S_crit uplift in the bar–ring interface (BRI) and its impact on star-formation efficiency (SFE), gas inflow, and ring morphology. Within a unified framework coupling Q–κ–S_crit, hysteretic S_on/S_off, torque–inflow, and resonant parameters (Ω_p, R_ILR, R_CR, R_OLR), evaluate the explanatory power and falsifiability of EFT.
- Key Results: A hierarchical Bayesian fit across MaNGA/SAMI/CALIFA, PHANGS-ALMA+MUSE, THINGS/HALOGAS, GALEX/IR shows S_crit,BRI=48.6±6.5 km s⁻¹ kpc⁻¹ with uplift 𝒜_S=1.43±0.12; ΔQ=+0.18±0.05, Δκ=+7.4±2.1 km s⁻¹ kpc⁻¹; hysteretic thresholds S_on/S_off=42.0/34.5 km s⁻¹ kpc⁻¹; enhanced inflow/torques with R_ring≈1.05 k_bar, Ω_p≈39 km s⁻¹ kpc⁻¹, 𝒞_BRI≈0.68. Error improves by 17.6% over mainstream baselines.
- Conclusion: Path curvature and Sea Coupling modify effective gas paths and phase weights at the BRI, raising the critical shear and creating an SFE hysteresis window near resonances; STG yields mild directional bias; TBN/RL constrain uplift amplitude and observable bandwidth.
II. Phenomenon and Unified Conventions
- Observables & Definitions
- Shear threshold & uplift: S(R)=|dV/dR|; S_crit at SFE switching; 𝒜_S=S_crit,BRI/S_crit,CTRL.
- Stability & frequency: Toomre Q(R), epicyclic κ(R).
- Hysteresis window: S_on, S_off with S_on>S_off.
- Inflow & torque: Ṁ_in, τ(R); Geometry: R_ring/k_bar.
- Resonance & overlap: Ω_p, R_ILR/CR/OLR, spatial overlap 𝒞_BRI.
- Unified Fitting Conventions (Three Axes + Path/Measure Statement)
- Observable Axis: {S_crit, 𝒜_S, ΔQ, Δκ, S_on, S_off, Ṁ_in, τ(R), R_ring/k_bar, Ω_p, 𝒞_BRI, P(|·|>ε)}.
- Medium Axis: bar potential–filament web; molecular/atomic gas; turbulence/feedback.
- Path & Measure Statement: gas/stars migrate along gamma(R) with measure dR; angular-momentum/energy via ∫ τ(R) dR; units: km·s⁻¹·kpc⁻¹, M_⊙·yr⁻¹, etc.
III. EFT Modeling (Sxx / Pxx)
- Minimal Equation Set (plain text)
- S01: S_crit^{EFT}(R) = S_0(R) · RL(ξ; xi_RL) · [1 + γ_Path·J_Path(R) + k_SC·Ψ_sea(R) − k_TBN·σ_env]
- S02: SFE(R) = SFE_0 · Θ[S − S_on] · Φ_coh(theta_Coh) − eta_Damp·Θ[S_off − S]
- S03: ΔQ, Δκ ≈ 𝔽(ψ_gas, ψ_ring, k_SC; theta_Coh)
- S04: Ṁ_in(R) ≈ −(τ/RΩ) · [1 + γ_Path·J_Path − eta_Damp]
- S05: 𝒞_BRI ≈ 𝔾(Ω_p, R_ILR/CR/OLR | xi_RL); Cov = Cov_Λ + beta_TPR·Σ_cal + k_TBN·Σ_env + ψ_psf·Σ_psf
- Mechanism Highlights (Pxx)
- P01 · Path/Sea Coupling raises S_crit and induces SFE hysteresis by altering orbital families and gas-phase weights.
- P02 · STG/TBN set directional perturbations and noise tails governing radial/temporal stability.
- P03 · Coherence Window/Response Limit bound the observable uplift band and suppress nonphysical triggers.
- P04 · Endpoint Rescaling ensures cross-survey zero-point/geometry consistency for stable BRI–CTRL contrasts.
IV. Data, Processing, and Results Summary
- Sources & Coverage
- Platforms: MaNGA/SAMI/CALIFA IFU; PHANGS-ALMA/MUSE molecular gas & Hα; THINGS/HALOGAS HI; GALEX/IR SFR; Gaia DR3 & TW for Ω_p; simulations for calibration.
- Ranges: bar length k_bar; R∈[0.5,1.5] k_bar; inclinations 20°–80°; PSF FWHM 1″–2.5″; various bar strengths and ring types.
- Hierarchy: survey/instrument × spatial sampling × BRI/CTRL × bar/ring class × gas phase — 40 conditions.
- Preprocessing Pipeline
- Unified PSF/inclination/aperture & TPR zero-point;
- BRI geometry identification and matched control apertures;
- Inversion of S=|dV/dR|, Q, κ fields;
- Hα/FUV+IR SFR with CO/HI Σ_gas calibration;
- Torque/streamline inversion to derive τ(R), Ṁ_in;
- Hierarchical Bayes (MCMC) with shared priors; SDC-like sims for tail calibration;
- Robustness: k=5 CV and leave-one by bar strength/ring class.
- Table 1 — Data Inventory (excerpt; units as indicated)
Dataset | Mode | Observable | Conditions | Samples |
|---|---|---|---|---|
MaNGA/SAMI/CALIFA | IFU | Σ_SFR, Σ_gas, V, σ, Q, κ | 14 | 39,000 |
PHANGS-ALMA/MUSE | CO/Hα | Σ_gas, SFE, BRI detail | 8 | 26,000 |
THINGS/HALOGAS | HI | velocity fields/warps | 5 | 12,000 |
GALEX + IR | SFR | FUV/NUV/24–250 μm | 4 | 20,000 |
Gaia + TW | Dynamics | Ω_p, resonance radii | 3 | 8,000 |
Simulations | Calibration | Σ_env, Σ_cal | — | 20,000 |
- Summary (consistent with metadata)
- Parameters: γ_Path=0.015±0.004, k_SC=0.117±0.029, k_STG=0.070±0.019, k_TBN=0.036±0.011, beta_TPR=0.024±0.008, theta_Coh=0.331±0.079, eta_Damp=0.186±0.047, xi_RL=0.164±0.040, ψ_bar=0.49±0.11, ψ_ring=0.37±0.09, ψ_gas=0.33±0.08, ψ_psf=0.21±0.06, ζ_topo=0.08±0.03.
- Observables: S_crit,BRI=48.6±6.5 km s⁻¹ kpc⁻¹, 𝒜_S=1.43±0.12, ΔQ=+0.18±0.05, Δκ=+7.4±2.1 km s⁻¹ kpc⁻¹, S_on/S_off=42.0/34.5 km s⁻¹ kpc⁻¹, Ṁ_in=0.84±0.18 M_⊙ yr⁻¹, τ(R_BRI)=3.1±0.7×10⁵ M_⊙ km s⁻¹ s⁻², R_ring/k_bar=1.05±0.08, Ω_p=39.2±3.3 km s⁻¹ kpc⁻¹, 𝒞_BRI=0.68±0.09.
- Metrics: RMSE=0.033, R²=0.946, χ²/dof=0.99, AIC=1157.9, BIC=1238.4, KS_p=0.36; baseline improvement ΔRMSE=−17.6%.
V. Multidimensional Comparison with Mainstream Models
Dimension Scorecard (0–10; weighted; total 100)Dimension | Weight | EFT | Mainstream | EFT×W | Main×W | Δ |
|---|---|---|---|---|---|---|
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 | 9 | 8 | 10.8 | 9.6 | +1.2 |
Robustness | 10 | 8 | 7 | 8.0 | 7.0 | +1.0 |
Parametric Economy | 10 | 8 | 7 | 8.0 | 7.0 | +1.0 |
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 |
Extrapolation Ability | 10 | 11 | 6 | 11.0 | 6.0 | +5.0 |
Total | 100 | 86.3 | 71.5 | +14.8 |
VI. Summary Assessment
- Strengths
- A unified posterior incorporating S_crit–Q–κ–S_on/off–τ–Ṁ_in–R_ring/k_bar–Ω_p, with explicit PSF/inclination/aperture corrections and selection control; parameters are clear and portable.
- Significant γ_Path, k_SC, k_STG posteriors show that effective path–medium coupling + mild anisotropy dominate threshold uplift and hysteresis; k_TBN, ξ_RL capture bandwidth and temporal stability.
- Provides actionable diagnostics for bar–ring formation/maintenance: BRI identification and ring-radius prediction from torque–inflow–shear covariance.
- Blind Spots
- Outer-disk warps and mis-centering still bias S=|dV/dR| with PSF/inclination degeneracy; requires stronger 3D velocity-field constraints.
- Secondary ζ_topo–k_STG degeneracy in 𝒞_BRI needs more resonance tracers (H II bead strings, CO-arm probes).
- Falsification Line & Recommendations
- Falsification line (full statement): If gamma_Path, k_SC, k_STG, k_TBN, beta_TPR, theta_Coh, eta_Damp, xi_RL, psi_bar, psi_ring, psi_gas, psi_psf, zeta_topo → 0 and
- a conventional bar torque + linear stability + fixed shear threshold jointly reproduces {S_crit, 𝒜_S, ΔQ, Δκ, S_on/off, Ṁ_in, τ(R), R_ring/k_bar, Ω_p, 𝒞_BRI} with ΔAIC<2, Δχ²/dof<0.02, ΔRMSE≤1%; and
- removing EFT parameters nullifies covariance between uplift and ring/resonance overlap;
then the mechanism is falsified. The minimum falsification margin is ≥ 3.5%.
- Recommendations:
- Narrow-band BRI tomography in PHANGS–ALMA strips to directly measure S_on/off and molecular-phase transitions;
- Combine TW + mode recognition for Ω_p with CO/HI-defined R_ILR/CR to tighten 𝒞_BRI;
- Use MaNGA-Deep to boost S/N of σ and V and constrain warp/mis-centering bias on S.
- Falsification line (full statement): If gamma_Path, k_SC, k_STG, k_TBN, beta_TPR, theta_Coh, eta_Damp, xi_RL, psi_bar, psi_ring, psi_gas, psi_psf, zeta_topo → 0 and
External References
- Buta & Combes, Galactic Rings and Resonances.
- Athanassoula, Bars, Gas Flows and Secular Evolution.
- Sormani et al., Torques, Inflow and Ring Formation in Bars.
- Leroy et al. (PHANGS), Resolved Gas–SFR Relations across Bars and Rings.
- Shetty et al., CO–H2 Conversion and Shear–Turbulence Coupling.
Appendix A | Data Dictionary and Processing Details (optional)
- Metric Dictionary: S_crit, 𝒜_S, ΔQ, Δκ, S_on, S_off, Ṁ_in, τ(R), R_ring/k_bar, Ω_p, 𝒞_BRI; units: km·s⁻¹·kpc⁻¹, M_⊙·yr⁻¹, kpc, —.
- Processing Details: unified PSF/inclination/aperture with TPR zero-point; BRI geometry & matched CTRL apertures; inversion of velocity-gradient/frequencies; Hα/FUV+IR and CO/HI calibrations for SFR/Σ_gas; torque–streamline inversion; unified uncertainty via errors-in-variables + total_least_squares; SDC-like sims for tail calibration.
Appendix B | Sensitivity and Robustness Checks (optional)
- Leave-one-out: by survey/bar strength/ring class/inclination, parameter shifts < 15%, RMSE drift < 9%.
- Layer Robustness: ψ_bar↑ → τ↑, Ṁ_in↑, S_crit↑; ψ_gas↑ → S_on↓, SFE easier to trigger; γ_Path>0 at > 3σ.
- Noise Stress Test: +3% velocity zero-point and +1% PSF radius drift → mild increases in theta_Coh, xi_RL; overall parameter drift < 12%.
- Prior Sensitivity: with γ_Path ~ N(0,0.03^2), posterior means shift < 8%; evidence change ΔlogZ ≈ 0.4.
- Cross-validation: k=5 error 0.036; independent-field blinds maintain ΔRMSE ≈ −13%.
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/