TY  - GEN
UR  - https://archiv.ub.uni-heidelberg.de/volltextserver/14341/
A1  - Gonçalves Netto, Dorival
Y1  - 2013/01//
ID  - heidok14341
AV  - public
TI  - NLO Predictions for New Physics at the LHC
N2  - New physics searches are one of the main aims of the CERN Large Hadron Collider. In most cases this entails  the study  of  small expected signals versus huge backgrounds. Therefore, theoretically  precise predictions for  collider observables are crucial for the analysis of any possible new physics signature. A major improvement in this enterprise can be achieved through  the calculation of  the Next-to-leading order (NLO) QCD corrections for the process under scrutiny. Thus, in this thesis we focus on  the quantitative and qualitative impact of the NLO effects on some  important new physics signatures.
To do so we have resorted to the new, fully automized package MadGolem, to which this thesis has made major contributions. The following important LHC search channels  are examined herewith: i) scalar color-octet pair production; ii) associated squark--neutralino  production;  and iii) the pair production of squarks and gluinos. In all these cases we observe important QCD effects which lead to sizable quantum corrections  (K~1.3-2) and strongly suppressed theoretical uncertainties, which deplete from O(100%) at leading-order down to  O(30%) at NLO. Moreover, we have shown the NLO  distributions  to be in good agreement with those obtained via multi-jet merging. Finally, we have carried out  a comprehensive study on the implications of the usual simplifying assumptions taken in the literature and in current tools, e.g. squark mass degeneracy. 

ER  -