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We respond to two comments on our recent paper, Jeltema & Profumo (2014). Thefirst comment by Boyarsky et al. confirms the absence of a line from M31 in the3-4 keV energy range, but criticizes the energy range for spectral fitting onthe basis that (i) the background model adopted between 3-4 keV is invalidoutside that range and that (ii) extending the energy range multiple featuresappear, including a 3.5 keV line. Point (i) is manifestly irrelevant (the 3-4keV background model was not meant to extend outside that range), while closerinspection of point (ii) shows that the detected features are inconsistent andlikely unphysical. We demonstrate that the existence of an excess near 3.5 keVin the M31 data requires fitting a broad enough energy range such that thebackground modeling near 3.5 keV is poor to a level that multiple spuriousresidual features become significant. Bulbul et al. criticize our use ofWebGuide instead of the full AtomDB package. While a technically correctremark, this is only a red herring: our predictions are based on line ratios,and not on absolute emissivities; line ratios, for atomic transitions withsimilar peak temperatures, are largely temperature-independent, thus the lineratios we employed to draw our conclusions are substantially correct. Bulbul etal. also present a new analysis of their data at lower energy, which excludes asignificant Cl contamination to the 3.5 keV line. Cl emission was howeverpredicted to be subdominant in our original study. Both of the Bulbul et al.'scriticisms are thus inconsequential to the conclusions of our original study.Finally, we demonstrate that the multi-temperature models employed in Bulbul etal. are, in fact, inconsistent, based on the Ca XX to Ca XIX line ratio: weshow that the overestimated cluster plasma temperatures they employ lead togross underestimates of the K XVIII line emissivity.

Reply to Two Comments on "Dark matter searches going bananas the contribution of Potassium (and Chlorine) to the 3.5 keV line"