[Paper Review] The Standard Model from the LHC to future colliders: a contribution to the Workshop "What Next" of INFN

Stefano Forte, A. Nisati+17 more|arXiv (Cornell University)|May 6, 2015

Particle physics theoretical and experimental studies364 references3 citations

TL;DR

This review synthesizes the state of the Standard Model physics as of 2014, focusing on LHC results and future collider prospects. It outlines key measurements—Higgs boson properties, top quark physics, electroweak precision, and effective field theories—while advancing tools for precision calculations and Monte Carlo simulations to probe new physics beyond the Standard Model.

ABSTRACT

This Report summarizes the results of the activities in 2014 of the Standard Model Working Group within the workshop "What Next" of INFN. We present a framework, general questions, and some indications of possible answers on the main issue for Standard Model physics in the LHC era and in view of possible future accelerators.

Motivation & Objective

• To assess the status of the Standard Model following LHC data collected up to 2014, particularly the discovery of a 125 GeV Higgs boson.
• To identify critical measurements and theoretical tools needed to test the SM’s completeness and probe new physics at future colliders.
• To evaluate the role of precision electroweak physics, top quark properties, and effective field theories in constraining new physics scenarios.
• To recommend a balanced research strategy that maintains flexibility across precision measurements, direct searches, and model-building.
• To provide a framework for interpreting future data from HL-LHC, ILC, and FCC based on current theoretical and experimental capabilities.

Proposed method

• Systematic review of electroweak precision observables, including W and Z boson masses, using available theoretical and experimental tools.
• Application of effective field theory (EFT) frameworks, particularly dimension-6 operators, to interpret deviations in Higgs couplings and constrain new physics.
• Development and evaluation of higher-order QCD calculations and resummation techniques for jet and vector boson production.
• Integration of Monte Carlo event generators with NLO and NNLO QCD corrections, including merging with parton showers.
• Use of pseudo-observables to extract model-independent information from Higgs decay and production data.
• Analysis of jet substructure techniques (grooming, shapes) to probe new physics in boosted final states.

Experimental results

Research questions

• RQ1 What are the most sensitive probes of new physics in the Higgs sector, and how can they be extracted from LHC data?
• RQ2 How precisely can the top quark mass and couplings be measured, and what do they reveal about the electroweak sector?
• RQ3 To what extent can effective field theories describe deviations from the Standard Model in Higgs and vector boson couplings?
• RQ4 What are the prospects for improving precision in electroweak observables at future colliders like ILC and FCC?
• RQ5 How can theoretical tools such as higher-order QCD corrections and Monte Carlo generators be optimized to support future discovery potential?

Key findings

• The 125 GeV Higgs boson is consistent with the Standard Model within current experimental and theoretical uncertainties, but deviations in couplings remain a key target for future precision studies.
• Electroweak precision measurements of W and Z boson masses show good agreement with SM predictions, but improvements are needed to test new physics at the 10–100 GeV scale.
• Top quark mass and couplings are measured with increasing precision, and their consistency with SM predictions constrains new physics in the top sector.
• Effective field theory approaches at dimension-6 provide a robust framework to interpret deviations in Higgs couplings, with Snowmass studies setting benchmarks for future sensitivity.
• Higher-order QCD corrections and resummation techniques significantly improve the accuracy of jet and vector boson cross-section predictions, essential for background estimation.
• Monte Carlo tools with NLO+PS merging and NNLO+PS generators are advancing toward full precision, enabling reliable simulation of complex final states at future colliders.