Angular variables could be a good variable for selecting dark matter candidates. Due to reconstruction of MET, soft-terms usually inject a fake MET opposite to all hard objects, which make that diphoton background that should not present special MET direction induces a \MET opposite to the diphoton direction. This should be corercted for. One possible thing is to calibrate better the soft-terms. How? The main contribution to soft-terms that could induce such MEt is the cut pile-up jets.
Angular variables could be a good variable for selecting dark matter candidates. Due to reconstruction of MET, soft-terms usually inject a fake MET opposite to all hard objects, which make that diphoton background that should not present special MET direction induces a \MET opposite to the diphoton direction. This should be corercted for. One possible thing is to calibrate better the soft-terms. How? The main contribution to soft-terms that could induce such MEt is the cut pile-up jets.