The E_iso versus E_peak diagram. The blue solid line represents the Amati relation for the LGRB population, taken from Y. Liu et al. (2025). The deep blue and light blue shaded regions indicate 1σ and 3σ uncertainties, respectively. The yellow (Lc), red (Lw), green (LI), and purple (Llow) are results in different models, while the circles (θ_v = 10°), squares (θ_v = 20°), diamonds (θ_v = 45°), and stars (θ_v = 60°) denote different viewing angles. Magenta points denote observed FXTs (EP240414a and EP250108a), for which E_peak only has upper limits.