Publication

New Phenomenology Paper

November 18, 2020

Collider Physics Group

“Topping-up multilepton plus b-jets anomalies at the LHC with a Z’ boson“ , co-authored by A. Juste, together with T. Vazquez Schoeder and theorists E. Alvarez and M. Szewc, was recently submitted to the arXiv.

This paper studies several discrepancies in ttH and 4-tops searches at the LHC in multilepton plus b-jets final states, and develops a phenomenological New Physics model involving a Z’ boson that can account for them. This model provides a better fit to the experimental data than the Standard Model for a New Physics scale of approximately 500 GeV, and with a hierarchical coupling of the Z′ boson that favours the top quark and the presence of FCNC currents. It is also shown that the parameter space of the model that best fits the data could be probed with a significance exceeding 3 standard deviations with just the full Run-2 dataset.

Link to arXiv

Latest Group News

IFAE organization

New positions in the IFAE Organization

January 16, 2023

Mario Martinez, ICREA professor at IFAE and head of the Gravitational Waves Group, is the new Director of the Experimental Division and takes on the role of IFAE Deputy Director. Martine Bosman, retiring Director of the Experimental Division, assumes the status of IFAE Emeritus.

New Publication

New ATLAS group paper

January 12, 2023

The paper “Search for a new scalar resonance in flavour-changing neutral-current top-quark decays 𝒕 → 𝒒𝑿 (𝒒 = 𝒖, 𝒄), with 𝑿 → 𝒃𝒃bar, in proton-proton collisions at sqrt(s) = 13 TeV with the ATLAS detector” has been submitted to JHEP.

New Member

New Member in the ATLAS group

January 12, 2023

Javier Montejo Berlingen has joined the ATLAS group at IFAE as tenure-track Ramon y Cajal Researcher.