My research mostly deals with the phenomenology of new particles and interactions at colliders. The breaking of the electroweak symmetry and the stabilization of the electroweak scale has inspired ideas like the Higgs mechanism, supersymmetry, extra dimensions, technicolor and little Higgs models. However, a broader understanding may be reached with more model-independent approaches, such as effective field theories and simplified models.
I am studying how the parameters of these model-independent frameworks can be constrained by direct searches at high-energy colliders, such as the Large Hadron Collider, and by precision experiments at lower energies. Of special interest to me are precision analyses that would allow to reconstruct the underlying framework of a model from experimental data. On the technical side, this involves development of loop calculation techniques and Monte-Carlo tools.
Some of the new physics models quite naturally could explain the origin of ordinary matter and/or dark matter in the universe. This opens up striking connections between collider physics and astrophysics and cosmology.
- "QCD corrections to massive color-octet vector boson pair production," A. Freitas, D. Wiegand, JHEP 1709, 058 (2017)
- "Three-loop vacuum integrals with arbitrary masses," A. Freitas, JHEP 1611, 145 (2016)
- "The two-loop electroweak bosonic corrections to sin2 θbeff," I. Dubovyk, A. Freitas, J. Gluza, T. Riemann, J. Usovitsch, Phys. Lett. B 762, 184 (2016)
- "Numerical multi-loop integrals and applications," A. Freitas, invited review, Prog. Part. Nucl. Phys. 90, 201 (2016)
- "Pushing Higgs effective theory to its limits," J. Brehmer, A. Freitas, D. Lopez-Val, T. Plehn, Phys. Rev. D 93, 075014 (2016)
- "Integrating in the Higgs portal to fermion dark matter," A. Freitas, S. Westhoff, J. Zupan, JHEP 1509, 015 (2015)