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Appendix A: Additional figures for all models

<figure><img src="image_13.png" /><figcaption>**Fig. A.1.** Spectral evolution of models logP2p75, logP2p80, logP2p85, and logP2p90. The CMFGEN time sequences are computed at time steps $t_i$ such that $t_{i+1}/t_i = 1.1$. Here, we show fewer time steps for better visibility so that $t_{iplot+1}/t_{iplot} \sim 1.3$. As for Fig. 6, we illustrate the flux associated with H I lines (dark shade) and H β lines (light shade).</figcaption></figure>
Appendix A: Additional figures for all models

<figure><img src="image_13.png" /><figcaption>**Fig. A.1.** Spectral evolution of models logP2p75, logP2p80, logP2p85, and logP2p90. The CMFGEN time sequences are computed at time steps $t_i$ such that $t_{i+1}/t_i = 1.1$. Here, we show fewer time steps for better visibility so that $t_{iplot+1}/t_{iplot} \sim 1.3$. As for Fig. 6, we illustrate the flux associated with H I lines (dark shade) and H β lines (light shade).</figcaption></figure>
<figure><img src="image_14.png" /><figcaption>Fig. A.2. Same as Fig. A.1 but now for models logP2p95, logP3p00, logP3p10, and logP3p20.</figcaption></figure>
<figure><img src="image_14.png" /><figcaption>**Fig. A.2.** Same as Fig. A.1 but now for models logP2p95, logP3p00, logP3p10, and logP3p20.</figcaption></figure>
<figure><img src="image_15.png" /><figcaption>Fig. A.3. Same as Fig. A.1 but now for models logP3p35 and logP3p45.</figcaption></figure>
<figure><img src="image_15.png" /><figcaption>Fig. A.3. Same as Fig. A.1 but now for models logP3p35 and logP3p45.</figcaption></figure>
<figure><img src="image_16.png" /><figcaption>**Fig. A.4.** Evolution of the $H\alpha$ profile for our set of models. We show the flux obtained by accounting for all bound-bound transitions subtracted from the flux obtained by ignoring those associated with H1. The fluxes are normalized by the peak $H\alpha$ flux in the “full” model. These profiles are used to compute the ratio of the absorption to the emission flux in $H\alpha$ (see Fig. 7).</figcaption></figure>
<figure><img src="image_16.png" /><figcaption>**Fig. A.4.** Evolution of the $H\alpha$ profile for our set of models. We show the flux obtained by accounting for all bound-bound transitions subtracted from the flux obtained by ignoring those associated with H1. The fluxes are normalized by the peak $H\alpha$ flux in the “full” model. These profiles are used to compute the ratio of the absorption to the emission flux in $H\alpha$ (see Fig. 7).</figcaption></figure>