Hi, I'm writing my master's thesis in experimental particle physics. I have a sample of simulated signal events, from which i try to reconstruct the higgs boson in each event by adding up the four highest momentum Kaons, two positively charged, two negatively charged ones (setting up a search for higgs pseudoscalars). Normally they peak nicely at the higgs mass, but there is also a smaller peak right next to that on the left, which has to be from combinatorics since we only look at the signal simulation. My supervisors and me concluded that we simply choose a wrong kaon in our reconstruction, which is obvious. However, we cannot explain why this leads to a peak in our histogram... Is this a known phenomenon?