Artist's view of a Higgs event at ILC

Detector & Physics in Zeuthen for a Linear Collider

Physics > Higgs studies

Higgs studies

Recoil mass spectrum

e+ e- to H Z with H to b bbar and Z to mu mu Higgs recoil spectrum for 250 fb-1 and P(e+)=+30% and P(e-)=-80%

The process e+e-→ZH allows a measurement of the Higgs boson in the recoil mass spectrum against the Z-boson without any assumptions on the Higgs boson decay. Searching for leptonic (e+e-, µ+µ-) Z-boson decays allows a determination of

This analysis provides one of the key channels for the optimization of the ILC detector performance.


Higgs production at a photon linear collider

cross section for gamma gamma to b bbar gluon cross section for gamma gamma to c cbar gluon

The main backgrounds to an intermediate mass Standard Model Higgs production in photon collisions are the continuum b- and c-quark pair production; the light quarks are very efficiently rejected by the b-tagging. The cross sections of these processes are much higher than the cross sections of the signal, and depend on the polarisation of the colliding photons. Fortunately, when the two photons have the same helicity making the spin of the initial state equal to zero, the cross section in the LO is suppressed by a factor proportional to Mq2/s. However, this suppression is not maintained when a gluon is radiated and the resulting background is still very large compared to the signal. Such processes can mimic the 2-jets topology of the signal when two of the three partons are collinear, or when one of the partons is soft or directed down the beam pipe. Therefore, a reliable prediction of the background implies to consider the NLO QCD corrections.