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One of the research activities of our group at DESY is the study of Higgs boson(s) phenomenology at hadron colliders, such as the Large Hadron Collider (LHC) currently operating at the CERN laboratory in Geneva. Since the discovery in 2012 of a Higgs boson at the LHC, one of the most important task that now occupies the particle physics community is the measurement of its properties. In particular, this means measuring the rates of its various production and decays modes, with the aim of confirming or falsifying the predictions of the Standard Model (SM).

titleMain Higgs production processes at the LHC

Image RemovedHiggs production at the LHC, for a SM-like state, is dominated by the gluon fusion channel ("gg Fusion" diagram and "pp → H" line  in the plots on the left). This process is mediated by a loop of quark since the Higgs lacks a color charge and therefore it can not couple directly to gluons.

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Higgs as seen by the CMS detector at CERN.

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The Standard Model particles (left) and their superpartners (right).

Moreover, since we know that the SM

The SM, however, is an incomplete theory

from several different perspectives both observational

, which is evident from both an observational perspective (lack of a cold dark matter candidate, baryon asymmetry, gravity etc.)


as well as a theoretical perspective (hierarchy problem, strong CP problem etc.)

, another interesting research avenue is to study how other possible Higgs-states – often prescribed by theoretical extensions of the SM -- could appear at the LHC


Among the most widely studied extensions of the SM is Supersymmetry (SUSY). In its minimal incarnation, the so-called Minimal Supersymmetric Standard Model (MSSM), it predicts the existence of five physical Higgs states (three neutral and one pair of electrically charged bosons). Obviously one of the neutral states must be identified with the one discovered at the LHC with a mass of 125 GeV. However, in the MSSM, its couplings and production/decay rates can significantly differ from what is predicted by the SM.

At the LHC, the experiments therefore pursue two complementary avenues in the hunt for new physics in the Higgs sector: (1) Measuring the properties of the 125 GeV Higgs boson with the highest possible precision, thus looking for deviations from the SM properties; (2) searching for additional neutral and charged Higgs bosons. While the first can only give us indirect hints for new physics, the discovery of another Higgs state would be direct evidence for new physics.

For this year's summer student program at DESY


we propose

a few projects closely linked to these topics – and therefore

two projects on the subject of searching for additional Higgs bosons in the MSSM. This topic is indeed at the forefront of the current research in particle physics.

You can find


short descriptions of the projects in their specific pages, which you can access from the sidebar on the left. In addition, in the wiki you can find a page with some useful resources for your projects as well.

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Higgs as seen by the CMS detector at CERN.