# NP in FCNCs at LHCb

The project NP in FCNCs at LHCb is funded by a Marie Curie Intra-European Fellowship for Career Developement (IEF). The full title of the project is

**Exploring New Phenomena through Flavour Changing Neutral Currents with LHCb**

### Objectives

The main objective of the project is the study of rare flavour changing neutral current transitions in b-hadrons, where a b-quark decays into an s-quark and a pair of leptons. In the Standard Model of particle physics these decays are highly quantum-loop suppressed. In extensions of the Standard Model, new, heavy particles can appear and significantly contribute to these processes, affecting both their branching fractions as well as the angular distributions of the final state particles. The project concentrates on three areas of particular interest:

- A full angular analysis of the decays B0->K*0 mu+mu-, directly determining the generalized effective couplings (Wilson coefficients).
- An analysis of the related mode Bs->phi mu+mu-, determining both its branching fraction and performing a full angular analysis
- A test of lepton universality using the decay Bs->phi e+e- and comparing its branching fraction to the decay Bs->phi mu+mu-

### Public results

- "Angular analysis of the B0->K*0 mu+ mu- decay", JHEP 02 (2016) 104, arXiv:1512.04442
- "Angular analysis and differential branching fraction of the decay B0s->phi mu+ mu-", JHEP 09 (2015) 179, arXiv:1506.08777
- "Angular analysis of the decay B0->K*0 mu+mu-", LHCb-CONF-2015-002, https://cds.cern.ch/record/2002772?ln=en

- LHCb online event display https://lbevent.cern.ch/EventDisplay/index.html

### Presentations at international conferences

- "Latest results on rare decays from LHCb", C. Langenbruch, Moriond Electroweak 2015, arXiv:1505.04160 [hep-ex]

- "Electroweak penguin decays with di-leptons", C. Langenbruch, Beauty 2014, PoS Beauty2014 (2014) 051