arxiv ref: 1610.07922Title: Handbook of LHC Higgs Cross Sections: 4. Deciphering the Nature of the Higgs SectorAuthors: The LHC Higgs Cross Section Working GroupNode: ALU-FRCNRSDESYDFTTOETHUDURUGRESRs: ESR1ESR13ESR14ESR8Supervisor: BelangerEllwangerForteGehrmannGloverGrazziniHeinemeyerHeinrichKraussMaltoniMariottiPassarinoSchumacherSpannowskySpiraWeigleinWork Packages: WP2: Predictions and simulations of signal and backgroundWP3: ToolsWP1: Interpretation of DataMilestones: M1.2.1 Extraction of constraints on Higgs couplings from fits to all available data; discussion of model dependenceM1.2.2 Extraction of information on Higgs spin and CP propertiesM1.3.1 Constraints on physics beyond the SM, distinction between different modelsM1.4.1 Review of the current state and future directions in Higgs boson physicsM2.1.1 Specialised codes for the SM-like Higgs boson scenarioM2.1.2 Better control of theoretical uncertainties for the SM-like Higgs boson scenarioM2.2.1 Precision calculations for vector boson scatteringM2.2.3 Standardised description for non-standard Higgs boson interactionsM2.2.4 Interpretation of experimental data in the light of M2.2.3M2.3.1 Validation of key Higgs background processes and evaluation of uncertainties derived from extrapolating them to signal regionsM2.3.2 Better control of theoretical uncertaintiesM2.3.3 Specialised codes for low multiplicity background processesM3.1.1 Tools for boosted objects & fat jetsM3.1.2 Fast simulation and reconstruction tools for the LHCM3.3.3 Improved PDFs using LHC data