The Q${}_{1,2}$-Q${}_7$ interference contributions to b → s γ at $O$(α${}_s^2$) for the physical value of m${}_c$

The $\overline{B}$ → X${}_s$γ branching ratio is currently measured with around 5% accuracy. Further improvement is expected from Belle II. To match such a precision on the theoretical side, evaluation of $O$(α${}_s^2$) corrections to the partonic decay b → X${}_s^{part}$γ are necessary, which includes the b → s γ, b → s gγ, b → s ggγ, b → $sq\overline{q}$γ decay channels. Here, we evaluate the unrenormalized contribution to b → s γ that stems from the interference of the photonic dipole operator Q${}_7$ and the current-current operators Q${}_1$ and Q${}_2$. Our results, obtained in the cut propagator approach at the 4-loop level, agree with those found in parallel by Fael et al. who have applied the amplitude approach at the 3-loop level. Partial results for the same quantities recently determined by Greub et al. agree with our findings, too.