Fit coefficients for $X_{\mathrm{max}}$ mean and variance parameterisations (SIBYLL/EPOS/QGSJet)

$X_{\mathrm{max}}$ moment and distribution parameterizations (CONEX-based) This Zenodo repository contains plain-text outputs used to build and validate parametrizations of the atmospheric depth of shower maximum, $X_{\mathrm{max}}$, derived from CONEX simulations.More details can be found on arXiv: All files are provided separately for the three hadronic interaction models:- SIBYLL 2.3e- EPOS LHC-R- QGSJet III-01 Contents 1) CONEX moments tables: conex_*.xmaxTables of $X_{\mathrm{max}}$ moments directly extracted from the CONEX simulations. For each hadronic interaction model and primary nucleus, the file reports (as a function of energy):- the mean $\langle X_{\mathrm{max}} \rangle$ and its statistical uncertainty,- the variance $\sigma^2(X_{\mathrm{max}})$ and its uncertainty. Units- $\langle X_{\mathrm{max}} \rangle$: g cm$^{-2}$- $\sigma^2(X_{\mathrm{max}})$: g$^2$ cm$^{-4}$ 2) CONEX binned distributions: conex_*.histBinned $X_{\mathrm{max}}$ distributions from the CONEX simulations. - Range: $X_{\mathrm{max}} \in [0, 2000]$ g cm$^{-2}$- Number of bins: $N = 100$- Bin width: $\Delta X_{\mathrm{max}} = 20$ g cm$^{-2}$ The entries are raw counts per bin. 3) Mean $X_{\mathrm{max}}$ parametrization coefficients: xmax_mean_*_EVPS2026.txtBest-fit coefficients of the parametrization for the mean $X_{\rm max}$. File format1. Row 1: best-fit parameters $(a_0, a_1, b_0, b_1)$2. Row 2: corresponding parameter uncertainties3. Row 3: $\chi^2$ and the number of degrees of freedom (ndf) 4) Variance parametrization coefficients: xmax_sigma2_*_EVPS2026.txtBest-fit coefficients of the parametrization for the variance $\sigma^2(X_{\rm max})$. A keyword in the filename specifies the chosen functional form for $\sigma^2$, e.g.- `pol2` (polynomial)- `exp` (exponential) File format1. Row 1: best-fit parameters - Polynomial model: $(c_0, c_1, c_2, d_0, d_1, d_2)$ - Exponential model: $(f_0, f_1, g_0, g_1)$2. Row 2: corresponding parameter uncertainties3. Row 3: $\chi^2$ and ndf 5) Generalized Gumbel distribution coefficients: gumbel_params_*_EVPS2026.txtBest-fit coefficients of the generalized Gumbel parametrization of the full $X_{\rm max}$ distributions. For each hadronic interaction model, the file reports the 21 coefficients entering the parametrizations of the three Gumbel parameters $(\mu, \beta, \lambda)$. Coefficients are denoted as:- $p_k^{(i)}$ with $i \in \{\mu, \beta, \lambda\}$ and $k = 0, 1, 2$ Notes on usage - All files are provided in plain-text format for ease of parsing in analysis pipelines.- Histogram files contain unnormalized counts; users should normalize as needed for likelihood fits or PDF construction.- The parametrization coefficient files include both best-fit values and uncertainties, plus goodness-of-fit information ($\chi^2$, ndf). Suggested citation If you use these data products or parametrizations in a publication, please cite: Contact For questions, bug reports, or requests (e.g., additional primaries/models or format clarifications), please contact the authors at [e-mail].