Grupos de investigación - Higgs properties at colliders / Propiedades del Higgs en colisionadores

The project will contain a series of research lines: 1. Higgs Physics searches in the SM. The Higgs particle has been discovered in 2012 and from that much of the experimental efforts have focussed in increasing the precision on the parameters describing this particle. The improvements in measuring processes where the Higgs participates requires at the same time more precise theoretical predictions. Our group is deeply involved in interpreting the experimental data in terms of the SM predictions, including very high quantum corrections. This also represents one of the research lines of this project, connected to the participation of members of our project in the LHC Higgs working group 2. 2. Higgs Physics searches in BSM. The SM cannot be the final theory describing Nature and the Higgs may or may not be the only elementary scalar field as described in the SM. Neutrino masses, Dark Matter (DM) existence and the observed baryon asymmetry of the Universe require theories beyond de SM in order to the explained. Many of them do predict modification of the SM scalar sector and therefore it is necessary to first categorise the different ways the SM Higgs particle paradigm can be modify and precisely determine the scalar parameters to then compare with the experimental data. Pinpointing the natura of the Higgs particle, either coinciding with the SM prediction or an elementary or composite object with deviations from the SM couplings to the other particles of the SM is a crucial goal and is one of our research lines. All the members of our project are experts in BSM theories and in analysing their effects at colliders. 3. Higgs physics searches in Supersymmetry. Among the various BSM theories, low-scale supersymmetry (SUSY) remains one of the most compelling candidates. It offers a unified framework that simultaneously accommodates a viable DM particle, protects the electroweak scale from destabilizing quantum corrections, and provides solutions to other theoretical challenges of the SM, including the electroweak vacuum¿s potential instability and the imperfect unification of gauge couplings. The minimal supersymmetric SM extension (MSSM) predicts the existence of superpartners for each SM particle: gauginos/higgsinos and sleptons/squarks are the superpartners of the gauge/Higgs bosons and of the leptons/quarks, respectively. In this framework, the lightest supersymmetric particle becomes a viable DM candidate, provided that a discrete symmetry known as R-parity is conserved. In addition the MSSM Higgs sector consists of two scalar doublets, resulting in a physical spectrum with three neutral Higgs bosons and a pair of charged Higgs bosons, which provide very distinctive signals that are being searched for and/or could be discovered at the LHC. 4. Effective Field Theories for the Higgs particle. Besides the activity of studying precise BSM models that may impact the scalar sector of the SM, it may perfectly be the case that the correct model has not been find yet. In this case, the best approach is to use effective field theories to identify sectors of the theory that may present deviations from the SM predictions. In case of a positive observation of such a deviation, we could be able to identify corresponding properties of the Higgs that are affected. The goal of this research line is to investigate the different effective descriptions associated to the Higgs, identify the differences and similarities, pinpoint the smoking guns of the various proposals. Also in this case, members of the project are experts in EFT descriptions and are capable of make advances relevant for the community.

Publicaciones más relevantes

1. K. Asteriadis, S. Dawson, P. P. Giardino and R. Szafron, Impact of Next-to-Leading-Order Weak Standard-Model-Effective-Field-Theory Corrections in e+e -> ZH, Phys. Rev. Lett. 133 (2024) no.23, 231801, arXiv:2406.03557 [hep-ph] 2. M. Cepeda, J. M. No, C. Ramos, R. M. Sandá Seoane, J. Zurita, Exotic h ¿ Za Higgs decays into ¿ leptons, JHEP 07 (2025) 009 [arXiv:2503.08781]. 3. R. Capucha, A. Lozano-Onrubia, L. Merlo, J.M. No and R. Santos, V-Associated Production and Vector Boson Fusion as an LHC Signature of CP Violation, arXiv:2507.05942 [hep-ph]. 4. L. Bellafronte, S. Dawson, C. Del Pio, M. Forslund and P. P. Giardino, Complete NLO SMEFT Electroweak Corrections to Higgs Decays, arXiv:2508.14966 [hep-ph]. 5. E. Arganda, M. de los Rios, A. D. Perez, S. Roy, R. M. Sandá Seoane and C. E. M. Wagner, Shedding Light on Dark Matter at the LHC with Machine Learning, arXiv:2509.15121 [hep-ph].

Proyectos más relevantes

1. 2023-2026: Física más allá del Modelo Estándar y Cosmología del Universo primitivo: Nuevas ideas y técnicas, with reference PID2021-124704NB -I00/AEI/10.13039/501100011033, funded by the Spanish MINECO. PI Guillermo Ballesteros and José Miguel No. Funds: 89.540€. 2. 2023-2026: Abriendo ventanas a nueva física, with reference PID2022-137127NB- I00/AEI/10.13039/501100011033, funded by the Spanish MINECO. PI Luca Merlo and Enrique Fernandez Martinez. Funds: 284.875€. 3. 2024-2029: Precision physics in the LHC era, RYC2022-038517-I, funded by MCIN/AEI/10.13039/501100011033 and El FSE invierte en tu futuro; PI Pier Paolo Giardino; Funds: 50.000€.

1. Ernesto Arganda a. ¿Supersimetría: en busca de la teoría perdida¿. Ciclo de Conferencias del IFT UAM-CSIC ¿El Paisaje de la Física Fundamental¿, Semana de la Ciencia 2021, Residencia de Estudiantes, Madrid, España. 4 de noviembre de 2021. b. ¿Escape Road: A la búsqueda de las científicas Nobel y no Nobel¿. Noche Europea de los Investigadores e Investigadoras 2022, La Casa Encendida, Madrid, España. 23 de septiembre de 2022. c. ¿Interacciones y materia al alcance de la mano (para todes)¿. ATLAS Masterclass 2023 - UNLP, Universidad Nacional de La Plata, Argentina. 12 de mayo de 2023. d. ¿A la caza de las partículas¿. Noche Europea de los y las Investigadoras 2025, Espacio Fundación Telefónica, Madrid, España. 26 de septiembre de 2025. e. ¿Interacciones y materia al alcance de la mano (para todes)¿. 10 charlas de divulgación científica de Física de Partículas en Institutos de Educación Secundaria de la Comunidad de Madrid (2022-2025). 2. Pier Paolo Giardino: a. ¿El bosón de Higgs, una linterna en la oscuridad¿, Nerd Nite, La Nave de Vidan, Santiago de Compostela, España, 23 de noviembre de 2022