The Journal of high energy physics/The journal of high energy physics, Mar 15, 2024
The recent observation of entanglement between top and anti-top quarks at the LHC opens the way t... more The recent observation of entanglement between top and anti-top quarks at the LHC opens the way to interpreting collider data with quantum information tools. In this work we investigate the relevance of quantum observables in searches of new physics. To this aim, we study spin correlations of tt pairs originating from various intermediate resonances, and compare the discovery reach of quantum observables compared to classical ones. We find that they provide complementary information and, in several notable cases, also the additional leverage necessary to detect new effects.
We compute the effects due to the virtual exchange (or the soft emission) of a scalar particle wi... more We compute the effects due to the virtual exchange (or the soft emission) of a scalar particle with generic couplings to the top quark in t t pair production at the LHC. We apply the results to two cases of interest, extending and completing previous studies. First, we consider the indirect search for light (m S < 2m t ) top-philic scalars with CP-even and/or CP-odd interactions. Second, we investigate how to set constraints on anomalous Yukawa couplings of the Higgs boson to the top quark. Our results show that the current precision of experimental data together with the accuracy of the SM predictions make such indirect determinations a powerful probe for new physics.
We study the quantum properties of top quark pairs in lepton colliders with unpolarised beams, in... more We study the quantum properties of top quark pairs in lepton colliders with unpolarised beams, including spin correlations, entanglement, and violation of Bell inequalities. We present analytical results in the SM and in the SMEFT and discuss several practical aspects, like the choice of quantisation axes and t t threshold effects. We also note a correspondence between parity symmetry and entanglement. We find that quantum observables exhibit a rich phenomenology in the SM, and can also provide additional leverage in detecting new physics residing at higher scales.
We study the LHC phenomenology of an Axion Like Particle (ALP) that couples only derivatively wit... more We study the LHC phenomenology of an Axion Like Particle (ALP) that couples only derivatively with the top quark at tree level. We inspect the radiatively induced couplings with the SM fermions and (gauge) bosons and the associated production and decay mechanisms of the ALP. We focus on the most challenging mass window that remains open for a top-philic ALP, i.e., the range between tens and hundreds of GeV. Not only ALP production processes but also virtual ALP contributions to final states with top quarks are considered in detail. We show how searches through resonant production, such as ALP production in association with a tt pair, are complementary to precision measurements of tt and tttt final states, the latter being competitive or even more powerful for a top-philic ALP in this mass window. Finally, we explore the scenario where the top-philic ALP acts as a mediator to a dark-matter sector, resulting in missing energy signatures at the LHC. We find that the LHC constraints from tt, tttt and ALP + jet production, together with those from tt + ALP production, can already exclude a large fraction of the parameter space leading to the correct relic abundance.
The recent observation of entanglement between top and anti-top quarks at the LHC opens the way t... more The recent observation of entanglement between top and anti-top quarks at the LHC opens the way to interpreting collider data with quantum information tools. In this work we investigate the relevance of quantum observables in searches of new physics. To this aim, we study spin correlations of tt pairs originating from various intermediate resonances, and compare the discovery reach of quantum observables compared to classical ones. We find that they provide complementary information and, in several notable cases, also the additional leverage necessary to detect new effects.
In questa tesi viene analizzato un possibile mesone formato da un quark top e un quark antitop ch... more In questa tesi viene analizzato un possibile mesone formato da un quark top e un quark antitop chiamato toponio usando la meccanica quantistica. Sono determinati i primi 6 livelli energetici degli orbitali S,P,D e F, la velocità e il raggio caratteristico del primo stato legato e lo splitting nei livelli S dovuto all'interazione spin-spin. Si ipotizza inoltre l'esistenza di una forza sconosciuta oltre il Modello Standard, mediata da una particela scalare, e se ne studia l'effetto sui livelli energetici determinati in precedenza. Data l'esistenza di questa forza si ha una diminuzione del tempo di formazione del toponio rispetto a quello previsto dal Modello Standard, si procederà quindi a stimare sommariamente l'intensità minima necessaria per questa forza affinché sia possibile la formazione di stati legati
Uploads
Papers by Simone Tentori