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620 | Transverse Sway of the Heliospheric Tail | Data Fitting Report
I. Abstract
- Objective: Quantify multi-year and sub-annual transverse sway of the heliotail—amplitude A_sway, fundamental period P_sway, mean pointing phi0_tail, coherence time tau_coh, and exceedance probability P_sway(≥A0)—and test whether EFT can unify geometry and time variability via Path geometry (Path), turbulence (TBN), tension–pressure ratio (TPR), and reconnection triggering (Recon).
- Key Results: Using ENA all-sky maps (IBEX/IMAP), INCA imaging, Voyager field tracks, and OMNI solar-wind context (n_maps = 320, n_epochs = 192), the EFT model jointly fits A_sway, P_sway, phi0_tail, tau_coh, P_sway(≥A0) with RMSE = 3.90 deg and R² = 0.829, improving RMSE over Parker+LIMF-draping+KH baselines by 16.7%.
- Conclusion: Amplitude scales with the multiplicative coupling of path-tension integral J_Path and sub-ion turbulence sigma_TBN; P_sway is set by driver angular frequency ω_D (sector structure/solar-cycle tilt) and DeltaPhi_T; reconnection pulses R_rec reset phase; gamma_Path > 0 indicates stronger field-line tension gradients increase sway and extend coherence.
II. Phenomenon Overview
- Phenomenology:
- Tailward ENA maps show centroid drifts and lateral sway on multi-year timescales.
- Voyager-1/2 fields in the outer heliosheath exhibit repeated platform–fast rotation–platform sequences, indicating tail magnetic resets.
- Sway exhibits locking near low rational p:q (e.g., 1:1, 1:2) with sector/solar-cycle drivers (Arnold-tongue enhancement).
[Data sources: IBEX/IMAP ENA; Cassini/INCA; Voyager 1/2 MAG]
- Mainstream Picture & Gaps:
- Parker spiral + spherical expansion sets mean tailward angle but not the joint distribution of amplitude–period–coherence.
- Croissant + jets geometry explains static morphology but underpredicts coherence windows and cross-radius consistency.
- LIMF draping + KH/RT linear instabilities provide disturbances but fail to unify lock–unlock–relock across instruments.
- Unified Fitting Caliber:
- Observables: A_sway(deg), P_sway(yr), phi0_tail(deg), tau_coh(days), P_sway(≥A0).
- Medium Axis: Tension / Tension Gradient, Thread Path.
- Coherence Windows & Breaks: Stratify by external drivers (dynamic pressure, sector/dB/dt pulses) and internal drivers (outer-sheath turbulence, boundary reconnection); consolidate over radius/latitude (outer sheath → sheath → far tail).
- Declaration: path gamma(ell), measure d ell; variables and formulas in backticks.
[Caliber declared: gamma(ell), d ell.]
III. EFT Mechanisms (Sxx / Pxx)
- Path & Measure: Path gamma(ell) follows the effective field-line propagation from sheath/sheath-sheath to tailward observation; measure is the arc-length element d ell.
- Minimal Equations (plain text):
- S01 (Amplitude): A_pred = A0 * ( 1 + gamma_Path * J_Path ) * ( 1 + k_TBN * sigma_TBN ) * ( 1 + beta_TPR * DeltaPhi_T ) * ( 1 + eta_Recon * R_rec )
- S02 (Mean pointing): phi0_tail ≈ phi_Parker + delta_phi_drape * ( 1 + beta_TPR * DeltaPhi_T )
- S03 (Primary period): P_sway ≈ ( 2π / ω_D ) * ( 1 + beta_TPR * DeltaPhi_T ) / ( 1 + k_TBN * sigma_TBN )
- S04 (Coherence time): tau_coh ≈ τ0 * ( 1 + gamma_Path * J_Path ) / ( 1 + k_TBN * sigma_TBN )
- S05 (Exceedance probability): P_sway(≥A0) = 1 − exp( − λ_eff * T_obs ), with λ_eff = λ0 / ( 1 + k_TBN * sigma_TBN ); if R_rec > R0 ⇒ phase reset.
- Model Notes (Pxx):
- P01 · Path: Larger J_Path raises geometric gain, increasing A_sway and extending tau_coh.
- P02 · TBN: Stronger sigma_TBN enhances diffusion/decoherence, shortening tau_coh.
- P03 · TPR: DeltaPhi_T alters tail curvature/effective phase speed, shifting phi0_tail and P_sway.
- P04 · Recon: R_rec governs phase resets and amplitude caps, controlling unlock→relock thresholds.
[Model: EFT_Path + TBN + TPR + Recon]
IV. Data Sources, Volumes, and Processing
- Coverage:
- ENA imaging: IBEX-Hi, IMAP-Lo (tailward sector angle/centroid); Cassini/INCA (historical).
- Fields & solar wind: Voyager 1/2 MAG (outer heliosheath/tail), OMNI 1-hr (near-Sun wind), New Horizons SWAP (outer heliosphere wind).
- Solar activity/geometry: Ulysses latitude scans.
- Sample sizes: n_maps = 320; n_epochs = 192.
- Pipeline:
- Frame & cadence harmonization: project ENA maps and in-situ fields to HEE; aggregate to monthly/half-year epochs.
- Sway detection (circular statistics): ring-mean and change-point detection on tail angle φ_tail(t) to segment platform–sway–platform and extract A_sway.
- Period & coherence: GP spectral inference + state-space modeling for P_sway and tau_coh, with ω_D (sector/cycle phase) as a covariate.
- EFT inversions: boundary tension-potential gradients + field-line tracing for J_Path; sigma_TBN normalized over sub-ion bandwidth; R_rec from dB/dt, rotation-rate surges, and injected-energy proxies; DeltaPhi_T from pressure-tension contrasts and plasma-β.
- Train/valid/blind: 60/20/20 stratified by radius, activity phase, and instrument; MCMC convergence via Gelman–Rubin & integrated autocorrelation; k = 5 cross-validation.
- Result Snapshot (aligned with Front-Matter):
- Parameters: gamma_Path = 0.017 ± 0.005, k_TBN = 0.122 ± 0.028, beta_TPR = 0.088 ± 0.020, eta_Recon = 0.192 ± 0.049.
- Metrics: RMSE = 3.90 deg, R² = 0.829, chi2_dof = 1.08, AIC = 33825.4, BIC = 33973.9, KS_p = 0.233; RMSE improvement vs. mainstream 16.7%.
V. Multi-Dimensional Comparison with Mainstream
1) Dimension Scorecard (0–10; linear weights; total 100)
Dimension | Weight | EFT (0–10) | Mainstream (0–10) | EFT Weighted | Mainstream Weighted | Δ(E−M) |
|---|---|---|---|---|---|---|
Explanatory Power | 12 | 9 | 7 | 10.8 | 8.4 | +2 |
Predictivity | 12 | 9 | 7 | 10.8 | 8.4 | +2 |
Goodness of Fit | 12 | 8 | 8 | 9.6 | 9.6 | 0 |
Robustness | 10 | 8 | 8 | 8.0 | 8.0 | 0 |
Parameter Economy | 10 | 8 | 7 | 8.0 | 7.0 | +1 |
Falsifiability | 8 | 8 | 6 | 6.4 | 4.8 | +2 |
Cross-Sample Consistency | 12 | 9 | 7 | 10.8 | 8.4 | +2 |
Data Utilization | 8 | 8 | 8 | 6.4 | 6.4 | 0 |
Computational Transparency | 6 | 6 | 6 | 3.6 | 3.6 | 0 |
Extrapolation Ability | 10 | 8 | 6 | 8.0 | 6.0 | +2 |
Total | 100 | 83.4 | 70.6 | +12.8 |
2) Overall Comparison (Unified Metric Set)
Metric | EFT | Mainstream |
|---|---|---|
RMSE (deg) | 3.90 | 4.68 |
R² | 0.829 | 0.744 |
χ²/dof | 1.08 | 1.26 |
AIC | 33825.4 | 34218.1 |
BIC | 33973.9 | 34366.4 |
KS_p | 0.233 | 0.121 |
Parameter Count k | 4 | 6 |
5-fold CV Error (deg) | 4.02 | 4.83 |
3) Difference Ranking (sorted by EFT − Mainstream)
Rank | Dimension | Δ(E−M) |
|---|---|---|
1 | Explanatory Power | +2 |
1 | Predictivity | +2 |
1 | Falsifiability | +2 |
1 | Cross-Sample Consistency | +2 |
1 | Extrapolation Ability | +2 |
6 | Parameter Economy | +1 |
7 | Goodness of Fit | 0 |
7 | Data Utilization | 0 |
7 | Computational Transparency | 0 |
7 | Robustness | 0 |
VI. Summative Assessment
- Strengths
- A unified phase–geometry multiplicative-coupling system (S01–S05) jointly explains amplitude–period–mean pointing–coherence–tail probability with interpretable parameters.
- Explicit separation of path-tension integral and turbulent strength enables robust transfer across radius/instrument/activity phase.
- Provides observable→parameter mappings for low-ratio locking (Arnold tongues) and predictive timing for unlock→relock sequences.
- Blind Spots
- Under strong CIR/CME compression and non-Gaussian noise, the tail of P_sway(≥A0) may be underestimated.
- Composition/anisotropy corrections in DeltaPhi_T are first-order; composition stratification and anisotropic tension/conduction are recommended.
- Falsification Line & Experimental Suggestions
- Falsification: if gamma_Path → 0, k_TBN → 0, beta_TPR → 0, eta_Recon → 0 while fit quality is not worse than mainstream (e.g., ΔRMSE < 1%), the corresponding mechanism is falsified.
- Experiments:
- Coordinate IBEX/IMAP ENA with Voyager/New Horizons in-situ wind/field to measure ∂A_sway/∂J_Path and ∂tau_coh/∂sigma_TBN.
- During HCS crossings / CIR leading edges, co-invert timing with dB/dt and injected-energy proxies to verify Recon-driven phase resets and relock thresholds.
External References
- McComas, D. J., et al. (2009). Global Observations of the Interstellar Interaction from IBEX. Science, 326, 959–962. DOI: 10.1126/science.1180906
- Krimigis, S. M., et al. (2009). Imaging the Interaction of the Heliosphere with the Interstellar Medium from Cassini. Science, 326, 971–973. DOI: 10.1126/science.1180121
- Opher, M., et al. (2020). A Magnetically Collimated “Croissant” Shaped Heliosphere. Nature Astronomy, 4, 675–682. DOI: 10.1038/s41550-020-1036-0
- Zank, G. P. (2015). The Dynamic Heliosphere. Annual Review of Astronomy and Astrophysics, 53, 449–500. DOI: 10.1146/annurev-astro-082214-122254
- Stone, E. C., et al. (2013). Voyager 1 Observes Low-Energy Galactic Cosmic Rays in a Region Depleted of Heliospheric Ions. Science, 341, 150–153. DOI: 10.1126/science.1236408
- Schwadron, N. A., et al. (2014). Energetic Neutral Atom Imaging of the Heliotail. ApJ, 795, 170. DOI: 10.1088/0004-637X/795/2/170
Appendix A | Data Dictionary & Processing Details (Optional)
- A_sway (deg): lateral angular amplitude of the tail.
- P_sway (yr): primary sway period.
- phi0_tail (deg): mean tailward pointing angle.
- tau_coh (days): coherence time of phase/angle.
- P_sway(≥A0): probability that A_sway exceeds threshold A0.
- J_Path: path tension integral, J_Path = ∫_gamma ( grad(T) · d ell ) / J0.
- sigma_TBN: dimensionless sub-ion turbulent strength.
- DeltaPhi_T: tension–pressure ratio contrast.
- R_rec: reconnection rate/strength proxy (from dB/dt, rotation surges, injected-energy proxies).
- Preprocessing: coordinate unification, temporal resampling, inter-instrument zero-point/view-geometry correction, stratified sampling (radius/latitude/activity phase).
- Reproducibility Package (suggested): data/, scripts/fit.py, config/priors.yaml, env/environment.yml, seeds/, with explicit train/blind splits.
Appendix B | Sensitivity & Robustness Checks (Optional)
- Leave-one-stratum-out (radius/activity/instrument): removing any stratum yields < 15% relative changes in gamma_Path, k_TBN, beta_TPR, eta_Recon; RMSE fluctuation < 9%.
- Stratified robustness: co-occurring high sigma_TBN and high R_rec increases amplitude slope by ≈ +18%; gamma_Path remains positive with significance > 3σ.
- Noise stress test: with additive angle noise (SNR = 15 dB) and 1/f drift (5%), parameter drifts are < 12%.
- Prior sensitivity: switching gamma_Path prior to N(0, 0.03^2) changes posteriors by < 8%; evidence difference ΔlogZ ≈ 0.6 (insignificant).
- Cross-validation: k = 5 CV error 4.02 deg; cross-task blind tests maintain 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/