High Energy Physics Group, Vinca, Belgrade


Related to the so far only discovery at the LHC, Higgs studies are in the focus of the future HEP projects. Belgrade HEP group is involved in several Higgs coupling measurements, at CLIC, CepC and ILC, addressing Higgs decays to muons and photons as well as Higgs to electroweak boson couplings. Higgs to ZZ bosons can be exploited to probe the sensitivity of the future electron-positron experiments to determine a CP structure of the Higgs sector. One PhD thesis related to Higgs studies is completed (CERN-THESIS-2017-349) and two are ongoing.

"Look deep into nature, and then you will understand everything better."

- Albert Einstein -

Our results

HZZ* decay at a 350 GeV CLIC

Higgs to ZZ decay is studied in the semileptonic final states at 350 GeV centre-of-mass energies. Analyses are done with full GEANT4 based simulation of detector for CLIC, taking into consideration all relevant physics and beam-induced background processes. Several similar studies have been done by us at CLIC, for the semileptonic and fully hadronic final states at 1.4 TeV (CERN-THESIS-2017-349) and for the semileptonic final state at 3 TeV.

Higgs CP structure at ILC and CLIC

There are numerous Higgs production processes available at the ILC (like HZ, WW-fusion,
ZZ-fusion) at various center-of-mass-energies, that offer a plethora of possibilities for
CP violation measurements in the Higgs sector. The correlation
between spin orientations of vector bosons from a Higgs production (or decay) can be extracted from the angle Φ between the production (decay) planes. CPV in Higgs production in ZZ-fusion is under
study at 1 TeV ILC and 1.4 TeV CLIC. Ongoing PhD thesis (N. Vukašinović).

Hγγ decay at a 3 TeV CLIC

The full simulation of Higgs to γγ branching fraction measurement is performed at 3 TeV CLIC as a PhD topic by G. Kacarevic. It is found that BR (H->γγ) can be measured with relative uncertainty of (5.5%) stat .± (1%) syst.

Hµ+µ- decay at the 1.4 TeV CLIC

We have shown in Eur.Phys.J. C75(2015)11, 515, as well as in CERN-THESIS-2017-349, that H-> mumu branching fraction is accessible at 1.4 TeV CLIC with the relative statistical uncertainty of 38% and a systematic uncertainty at the percent level.

Group for Experimental High Energy Physics
phone/fax: +381 (0) 11 6455 041