arXiv subjects

Adam K. Forster

Publications and source records attributed to Adam K. Forster.

2 recordsLinked to original sources

arXiv2021

Data-driven analysis of a SUSY GUT of flavour

We present a data-driven analysis of a concrete Supersymmetric (SUSY) Grand Unified Theory (GUT) of flavour, based on $SU(5)\times S_4$, which predicts charged fermion and neutrino mass and mixing, and where the mass matrices of both the Standard Model and the Supersymmetric particles are controlled by a common symmetry at the GUT scale. This framework also predicts non-vanishing non-minimal flavour violating effects, motivating a sophisticated data-driven parameter analysis to uncover the signatures and viability of the model. This computer-intensive Markov-Chain-Monte-Carlo (MCMC) based analysis includes a large range of flavour as well as dark matter and SUSY observables, predicts distributions for a range of physical quantities which may be used to test the model. The predictions include maximally mixed sfermions, $\mu\rightarrow e \gamma$ close to its experimental limit and successful bino-like dark matter with nearby winos (making direct detection unlikely), implying good prospects for discovering winos and gluinos at forthcoming collider runs. The results also demonstrate that the Georgi-Jarlskog mechanism does not provide a good description of the splitting of down type quark masses and charged leptons, while neutrinoless double beta decay is predicted at observable rates.

hep-ph↗

arXiv2021

Muon g-2, Dark Matter and the Higgs mass in No-Scale Supergravity

We discuss the phenomenology of no-scale supergravity (SUGRA), in which the universal scalar mass is zero at the high scale, focussing on the recently updated muon g-2 measurement, and including dark matter and the correct Higgs boson mass. Such no-scale supergravity scenarios arise naturally from string theory and are also inspired by the successful Starobinsky inflation, with a class of minimal models leading to a strict upper bound on the gravitino mass m3/2 < 103 TeV. We perform a Monte Carlo scan over the allowed parameter space, assuming a mixture of pure gravity mediated and universal gaugino masses, using the SPheno package linked to FeynHiggs, MicrOmegas and CheckMate, displaying the results in terms of a Likelihood function. We present results for zero and non-zero trilinear soft parameters, and for different signs of gaugino masses, giving a representative set of benchmark points for each viable region of parameter space. We find that, while no-scale SUGRA can readily satisfy the dark matter and Higgs boson mass requirements, consistent with all other phenomenological constraints, the muon g- 2 measurement may be accommodated only in certain regions of parameter space, close to the LHC excluded regions for light sleptons and charginos.

hep-ph↗