that of without the low-rigidity term.

   Free parameters / Models   [**BIG**]{}   [**SLIM**]{}   [**QUAINT**]{}
  -------------------------- ------------- -------------- ----------------
           $K_{10}$                                       
           $\delta$                                       
            $\eta$               1 or            1        
       $\delta_{\rm l}$                                         N/A
         $s_{\rm l}$             0.05           0.05            N/A
         $R_{\rm l}$                                            N/A
         $V_{\rm A}$                            N/A       
         $V_{\rm c}$                            N/A       

  : Free parameters of the three benchmark models , , and . The first block of parameters is associated with the diffusion coefficient in the intermediate regime, and is common to all models. The second block is related to a potential low-rigidity break in the diffusion coefficient, or to purely non-relativistic effects. The last block is related to reacceleration and convection.[]{data-label="tab:free_params"}

Fitting strategy {#sec:fit_bc}
================

In this section, we explain the fitting strategy used to extract the benchmark propagation parameters for the models presented above (, , and ). Fits are performed with the  package [@JamesEtAl1975] interfaced with the  code [@Maurin2018], and in particular, asymmetric error bars on the parameters rely on the  algorithm. For more technical details and subtleties on the setup and the analysis, we refer the reader to Ref. [@DeromeEtAl2019].

### Modeling uncertainties

For each run, the fluxes of the elements from Beryllium (Be) to Silicon (Si) are computed assuming that $^{10}$B, $^{11}$B (and $^{10}$Be, decaying into 