Status and discovery prospects for light pseudoscalars in the NMSSM

While most BSM searches at the LHC focus on heavy new states, the NMSSM contains the possibility of new light states that have escaped detection due to their singlet nature. Here we focus on light pseudoscalars, investigating the parameter space impact of recent LHC searches for such light states stemming from the decay of the 125 GeV Higgs boson. It is shown that, though direct searches can not yet compete with the requirement of the 125 GeV scalar having SM-like couplings, the searches are touching the allowed parameter space and should make a phenomenological impact in the near future.Comment: To appear in the proceedings for EPS-HEP 201

Novel SM-like Higgs decay into displaced heavy neutrino pairs in U(1)' models

We examine the observability of heavy neutrino (nu_h) signatures of a U(1)' enlarged Standard Model (SM) encompassing three heavy Majorana neutrinos alongside the known light neutrino states at the the Large Hadron Collider (LHC). We show that heavy neutrinos can be rather long-lived particles producing distinctive displaced vertices that can be accessed in the CERN LHC detectors. We concentrate here on the gluon fusion production mechanism gg -> H_{1,2} -> nu_h nu_h, where H_1 is the discovered SM-like Higgs and H_2 is a heavier state, yielding displaced leptons following nu_h decays into weak gauge bosons. Using data collected by the end of the LHC Run 2, these signatures would prove to be accessible with negligibly small background.Comment: 30 pages, journal versio

Photon-induced contributions to di-lepton production at the LHC Run II

We report on recent studies of photon-induced (PI) contributions to di-lepton production and their implications for Beyond Standard Model (BSM) $Z^\prime$-bosons searches at the LHC.Comment: Proceedings of XXV International Workshop on Deep-Inelastic Scattering and Related Subjects, 3-7 April 2017, University of Birmingham, U

Real and virtual photons effects in di-lepton production at the LHC

We show the SM prediction of di-lepton production at the LHC where to the usual Drell-Yan production we add the contribution from Photon-Initiated processes. We discuss the effects of the inclusion of photon interactions in the high invariant mass region (TeV region) and their consequences on BSM heavy Z'-boson searches.Comment: 7 pages, 6 figures, Proceeding of Les Rencontres de Physique de la Vall\'ee d'Aoste, La Thuile 201

The effect of real and virtual photons in the di-lepton channel at the LHC

We present a study of di-lepton production at the CERN Large Hadron Collider with a particular focus on the contribution resulting from both real and virtual photons in the initial state. We discuss the region of phase space in which the invariant mass of the lepton pair is of the order of several TeV, where searches for new physics phenomena yielding a di-lepton signature are presently carried out. We study both the yield and associated uncertainties for all possible topologies in photon-induced di-lepton production and compare these with what is expected in the standard Drell-Yan channel, where quark-antiquark pairs are responsible for the production of lepton pairs. We analyse the impact of these QED contributions on the expected Standard Model background and on searches for new physics. In this latter case, we use the production of an extra heavy $Z^\prime$-boson predicted by the Sequential Standard Model (SSM) as a benchmark process.Comment: 9 pages, 5 figure

AFBA_{FB} as a discovery tool for Z′Z^\prime bosons at the LHC

The Forward-Backward Asymmetry (AFB) in $Z^\prime$ physics is commonly only perceived as the observable which possibly allows one to interpret a $Z^\prime$ signal by distinguishing different models of such (heavy) spin-1 bosons. In this article, we examine the potential of AFB in setting bounds on or even discovering a $Z^\prime$ at the Large Hadron Collider (LHC) and show that it might be a powerful tool for this purpose. We analyze two different scenarios: $Z^\prime$s with a narrow and wide width, respectively. We find that in both cases AFB can complement the cross section in accessing $Z^\prime$ signals.Comment: arXiv admin note: substantial text overlap with arXiv:1503.0267