Ph.D XXXIX

Supervisor: Marina Cobal

Room: Rizzi L2-12-BC

Mail: ricci.bernardo@spes.uniud.it

Research Project

Beyond Standard Model physics searches with different jets signatures with the ATLAS detector

Many well-motivated extensions of the Standard Model predict non-conventional collider signatures that challenge standard analysis techniques. This PhD research, carried out within the ATLAS experiment at CERN, focuses on searches for physics beyond the Standard Model with unconventional final states. The work targets dark sector models producing prompt, highly collimated lepton-jet signatures and supersymmetric scenarios with compressed mass spectra requiring the identification of low-momentum b-hadrons. Dedicated reconstruction, background estimation, and analysis strategies are developed to enhance sensitivity in these challenging regimes. In particular, optimized lepton-jet techniques and soft b-tagging algorithms are employed to extend the ATLAS discovery reach into regions poorly covered by conventional searches.