Measurement of the Higgs-Selfcoupling

Measuring the Higgs self-coupling is the final corner stone in establishing the Higgs mechanism as the origin of the masses of elementary particles. We currently investigate ways to improve this very challenging analysis, especially at the lowest possible center-of-mass energies near 500 GeV.

Measurement of the Higgs Total Decay Width

Electron-positron collider with sufficient center-of-mass energy offer a unique possibility for the model-independent determination of the total decay width of the Higgs by measuring the Higgs production cross-section via WW-fusion and the partial decay width of the Higgs in a pair of W bosons.

Measurement of the H→ μ+ μ- Decay Branching Ratio

Understanding the properties of the Higgs boson will be a key to uncover the new physics beyond the Standard Model. The Higgs decay into two muons is a very rare decay mode, but profits from the excellent tracking capabilities of the ILD detector. With the H20 operation scenario for the ILC, we expect to reach a relative precision of about 15% for this branching ratio.

Interpretation of Higgs precision measurements

Based on the measurement of the total Higgsstrahlung cross section, absolute coupling strengths can be extracted from a global fit combining all kinds of σ × BR measurements. Most recently, we adapted this interpretation from a κ-framework to an EFT-based fit, and tested the sensitivity of the extracted couplings to various example points of extensions of the Standard Model.

Other Higgs related thesis written in our Group

Icon LC-REP-2013-022 (751KB)