SUSY backgrounds to Standard Model calibration processes at the LHC

Understand

One of the first orders of business for LHC experiments after beam turn-on will be to calibrate the detectors using well understood Standard Model (SM) processes such as W and Z production and ttbar production.

• These familiar SM processes can be used to calibrate the electromagnetic and hadronic calorimeters, and also to calibrate the associated missing transverse energy signal.
• However, the presence of new physics may already affect the results coming from these standard benchmark processes.
• We show that the presence of relatively low mass supersymmetry (SUSY) particles may give rise to significant deviations from SM predictions of Z+jets and W+jets events for jet multiplicity $\ge 4$ or $\ge 5$, respectively.