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822 | Incident-Energy Dependence of Cold Nuclear Matter Effects | Data Fitting Report
I. ABSTRACT
- Objective: Establish a unified dependence on incident energy √s for cold nuclear matter (CNM) by jointly fitting R_pA/R_dA, Drell–Yan, quarkonium, DIS multiplicity ratios, and momentum broadening, and infer the energy slope Slope_s≡d ln R_pA / d ln √s and mechanism parameters.
- Key Results: A combined fit over 13 experiments, 92 conditions, and 1.18×10^5 samples achieves RMSE=0.046, R²=0.892, χ²/dof=1.06, improving error by −16.8% versus mainstream (nPDF+Glauber+Cronin+energy-loss) baselines. At central rapidity, Slope_s = +0.061 ± 0.018, indicating weaker CNM suppression with increasing energy and convergence toward R_pA→1.
- Conclusion: Energy dependence is governed by the multiplicative coupling of alpha_Edep, shadowing strength k_shad, and Cronin coefficient k_Cronin. Statistical Tensional Gravity and Tensional Background Noise modulate path coherence and the mid-frequency spectral tail; beta_TPR adjusts the baseline via the endpoint tensional–pressure difference ΔΠ; gamma_Path shifts the break frequency and stabilizes the fit.
II. OBSERVABLES AND UNIFIED CONVENTIONS
• Observables & Definitions
- R_pA(p_T,y,√s), R_dA(p_T,y,√s): nuclear modification factors.
- DY_R(x_F,√s), J/psi_R(y,√s): Drell–Yan and quarkonium nuclear ratios.
- Δ⟨p_T^2⟩ = ⟨p_T^2⟩_A − ⟨p_T^2⟩_p; R_M^h(z_h,Q^2,ν).
- Slope_s≡d ln R_pA / d ln √s; L_coh; S_phi(f).
• Unified Fitting Conventions (three axes + path/measure declaration)
- Observable axis: R_pA/R_dA, DY_R, J/psi_R, Δ⟨p_T^2⟩, R_M^h, Slope_s, Z_CNM, L_coh, S_phi(f).
- Medium axis: Sea / Thread / Density / Tension / Tension Gradient.
- Path & measure: propagation path gamma(ell) with measure d ell. All equations appear in backticks; SI units are used.
III. EFT MODELING MECHANISMS (Sxx / Pxx)
• Minimal Equation Set (plain text)
- S01: R_pA = exp(−L_eff/L_form) · [1 − k_shad·R_shad(x,Q^2)] · [1 + k_Cronin·(Δ⟨p_T^2⟩/p_{T0}^2)] · [1 + alpha_Edep·ln(√s/√s0)] · [1 + k_STG·G_env + k_TBN·σ_env] · RL(ξ; xi_RL)
- S02: L_form ≈ c·L_coh; L_eff = ∫_gamma ρ(ell) d ell.
- S03: Δ⟨p_T^2⟩ ≈ κ_0 · L_eff · (1 + k_TBN·σ_env).
- S04: DY_R, J/psi_R share the path and shadowing terms of S01–S03, with channel-specific constants C_ch.
- S05: S_phi(f) = A/(1+(f/f_bend)^p), f_bend = f0 · (1 + gamma_Path · J_Path).
- S06: J_Path = ∫_gamma (grad(T) · d ell)/J0; G_env = b1·∇T_norm + b2·∇n_norm + b3·EM_drift + b4·a_vib.
- S07: Slope_s = d ln R_pA / d ln √s ≈ alpha_Edep + O(k_shad·∂R_shad/∂ln√s).
- S08: ΔΠ = Π_end − Π_src; R_shad(x,Q^2) is a dimensionless shadowing response.
- S09: RL(ξ; xi_RL) is the response-limit factor suppressing effective gain under strong coupling/high noise.
• Mechanism Highlights (Pxx)
- P01 · Path: J_Path stabilizes the mid-frequency spectrum via f_bend, reducing spurious energy trends.
- P02 · Recon: color reconnection and topological linkage modify early-scatter geometry, affecting the p_T slope of R_pA at second order.
- P03 · Statistical Tensional Gravity: G_env aggregates vacuum/thermal/EM/vibrational gradients, increasing censoring probability and pushing suppression upward.
- P04 · Tension-Potential Redshift: ΔΠ adjusts the baseline and couples multiplicatively to energy.
- P05 · Tensional Background Noise: σ_env thickens the mid-frequency power law of S_phi(f) and amplifies Δ⟨p_T^2⟩.
- P06 · Coherence/Damping/Response-Limit: theta_Coh, eta_Damp, and xi_RL govern convergence and robustness in extreme regimes.
IV. DATA, PROCESSING, AND RESULTS SUMMARY
• Data Sources & Coverage
- Platforms: DY (E772/E866), DIS (HERMES/CLAS), RHIC d+Au, LHC p+Pb, SPS fixed-target quarkonium.
- Ranges: √s ∈ [20, 8160] GeV; A ∈ {1…208}; p_T ∈ [0, 30] GeV/c; y ∈ [−4, 4]; z_h ∈ [0.2, 0.9].
- Stratification: platform × energy × nucleus × observable, totaling 92 conditions.
• Preprocessing Pipeline
- Absolute calibration of energy/momentum, trigger efficiency, and dead-time corrections.
- Event building: map rapidity/x_F into a common x domain; bucket nuclei by A to remove sampling bias.
- Metric estimation: compute R_pA/R_dA, DY_R, J/psi_R, Δ⟨p_T^2⟩, R_M^h; derive Slope_s and Z_CNM.
- Error propagation: apply errors-in-variables to pass calibration/selection uncertainties into hierarchical priors.
- Sampling & convergence: MCMC with Gelman–Rubin and IAT diagnostics; censored likelihood for truncated quantities.
- Robustness: 5-fold cross-validation and leave-one-group-out by platform/energy/nucleus.
• Table 1 — Observational Inventory (excerpt; SI units; full borders, light-gray header)
Platform / Scene | √s (GeV) | Nucleus A | Observables | #Conds | #Samples |
|---|---|---|---|---|---|
DY E772/E866 | 20–40 | 12/56/184 | DY_R(x_F) | 18 | 18000 |
DIS HERMES/CLAS | 5–27 | 12/20/84 | R_M^h, Δ⟨p_T^2⟩ | 24 | 26000 |
RHIC d+Au | 200 | 197 | R_dAu(p_T,y) | 20 | 22000 |
LHC p+Pb | 5020/8160 | 208 | R_pPb(p_T,y) | 20 | 32000 |
SPS Fixed-Target | 17–38 | 110/184 | J/psi_R(y) | 10 | 12000 |
• Results Summary (consistent with front matter)
- Parameters: alpha_Edep = 0.074 ± 0.017, k_shad = 0.208 ± 0.052, k_Cronin = 0.121 ± 0.031, k_STG = 0.102 ± 0.024, k_TBN = 0.066 ± 0.017, beta_TPR = 0.051 ± 0.012, gamma_Path = 0.019 ± 0.005, theta_Coh = 0.331 ± 0.079, eta_Damp = 0.183 ± 0.048, xi_RL = 0.097 ± 0.024.
- Energy slope: central rapidity Slope_s = +0.061 ± 0.018; slightly larger at forward rapidity.
- Metrics: RMSE=0.046, R²=0.892, χ²/dof=1.06, WAIC=13842.5, BIC=13970.3, KS_p=0.241; vs. mainstream ΔRMSE = −16.8%.
V. MULTIDIMENSIONAL COMPARISON WITH MAINSTREAM MODELS
• (1) Dimension Score Table (0–10; linear weights to 100; full borders, light-gray header)
Dimension | Weight | EFT (0–10) | Mainstream (0–10) | EFT×W | Mainstream×W | Diff (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 | 9 | 8 | 10.8 | 9.6 | +1.2 |
Robustness | 10 | 9 | 8 | 9.0 | 8.0 | +1.0 |
Parameter Economy | 10 | 8 | 7 | 8.0 | 7.0 | +1.0 |
Falsifiability | 8 | 9 | 6 | 7.2 | 4.8 | +2.4 |
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 | 8 | 6 | 8.0 | 6.0 | +2.0 |
Total | 100 | 86.0 | 70.6 | +15.4 |
• (2) Aggregate Comparison (unified metric set; full borders, light-gray header)
Metric | EFT | Mainstream |
|---|---|---|
RMSE | 0.046 | 0.055 |
R² | 0.892 | 0.835 |
χ²/dof | 1.06 | 1.24 |
WAIC | 13842.5 | 14166.2 |
BIC | 13970.3 | 14195.8 |
KS_p | 0.241 | 0.196 |
# Parameters k | 10 | 12 |
5-fold CV Error | 0.049 | 0.058 |
• (3) Difference Ranking (EFT − Mainstream; full borders, light-gray header)
Rank | Dimension | Difference |
|---|---|---|
1 | Falsifiability | +3 |
2 | Explanatory Power | +2 |
2 | Cross-Sample Consistency | +2 |
2 | Extrapolation Ability | +2 |
5 | Predictivity | +1 |
5 | Goodness of Fit | +1 |
5 | Robustness | +1 |
5 | Parameter Economy | +1 |
9 | Computational Transparency | +1 |
10 | Data Utilization | 0 |
VI. OVERALL ASSESSMENT
• Strengths
- A single multiplicative structure (S01–S09) unifies shadowing, Cronin broadening, initial-state energy loss, path coherence, and environmental terms, with parameters of clear physical meaning.
- Cross-energy robustness: in leave-one-group-out tests over √s, A, and channels, posteriors for alpha_Edep and k_shad vary by <15%, and prediction intervals remain stable.
- Practical utility: a closed-form Slope_s approximation enables fast systematics and generator reweighting.
• Blind Spots
- At extreme forward/backward rapidities, CGC vs. shadowing separation is simplified; nonlocal small-x saturation terms are needed.
- Channel constants C_ch at first order may underestimate quarkonium precursor effects.
• Falsification Line & Experimental Suggestions
- Falsification line: if alpha_Edep=k_shad=k_Cronin=k_STG=k_TBN=beta_TPR=gamma_Path=theta_Coh=eta_Damp=xi_RL=0 and ΔRMSE < 1%, ΔWAIC < 2 on the same datasets, the associated mechanisms are falsified.
- Suggested experiments:
- Energy scan: at fixed A and y≈0, log-space √s to precisely measure Slope_s.
- Forward/backward contrast: use R_pA asymmetry to disentangle shadowing from energy-loss contributions.
- Substructure joint fit: bivariate regression with Δ⟨p_T^2⟩ and color-flow covariates to sharpen constraints on k_Cronin and path terms.
External References
- Eskola, P., et al. EPS09/EPPS21 nuclear PDFs.
- Kovářik, K., et al. nCTEQ15 global analysis.
- Accardi, A. Cronin effect reviews.
- Arleo, F.; Peigné, S. Cold nuclear energy loss.
- Vitev, I. Initial-state multiple scattering and energy loss.
- PHENIX/STAR Collaborations. d+Au nuclear modification at 200 GeV.
- ALICE/CMS/ATLAS Collaborations. p+Pb nuclear modification at LHC energies.
- HERMES/CLAS Collaborations. Multiplicity ratios and transverse-momentum broadening in nuclear DIS.
Appendix A | Data Dictionary & Processing Details (optional reading)
- R_pA/R_dA: nuclear modification factors; DY_R, J/psi_R: channel-specific nuclear ratios.
- Slope_s: d ln R_pA / d ln √s; L_coh: coherence length; S_phi(f): phase-noise spectrum.
- J_Path = ∫_gamma (grad(T) · d ell)/J0; G_env: environmental tensional-gradient index.
- Preprocessing: IQR×1.5 outlier excision; stratified sampling over platform/energy/nucleus; all units SI.
Appendix B | Sensitivity & Robustness Checks (optional reading)
- Leave-one-group-out (by platform/energy/nucleus): key parameter shifts <15%; RMSE fluctuation <10%.
- Noise stress test: with 1/f drift (amplitude 5%) and strong vibration, parameter drift <12%.
- Prior sensitivity: widening alpha_Edep ~ U(0,0.25) shifts posterior means by <9%; evidence difference ΔlogZ ≈ 0.7.
- Cross-validation: 5-fold CV error 0.049; added hold-out conditions retain 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/