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Topics in Physics Beyond the Standard Model Phd Thesis Topics in Physics Beyond the Standard Model PhD Thesis Andrea Caputo IFIC - Universitat de València - CSIC Departamento de Física Teórica Programa de Doctorado en Física Under the supervision of Pilar Hernandez Gamazo Valencia, Julio 2020 Pilar Hernández Gamazo, catedrática del Departamento de Física Teórica de la Universidad de Valencia, Certifica: Que la presente memoria, ”Topics in physics Beyond The Standard Model” ,ha sido realizada bajo su dirección en el Instituto de Física Corpuscular, centro mixto de la Universidad de Valencia y del CSIC, por Andrea Caputo, y constituye su Tesis para optar al grado de Doctor en Ciencias Físicas. Y para que así conste, en cumplimiento de la legislación vigente, presenta en el Departamento de Física Teórica de la Universidad de Valencia la referida Tesis Doctoral, y firman el presente certificado. Valencia, Julio 2020 Pilar Hernández Gamazo List of Publications This PhD thesis is based on the following publications: • The seesaw path to leptonic CP violation [1] Caputo, A. and Hernandez, P. and Kekic, M. and Lopez-Pavon, J. and Salvado, J. Eur. Phys. J. C77 (2017) no.4, 258,[1611.05000]. • The seesaw portal in testable models of neutrino masses [2] Caputo, A. and Hernandez,P. and Lopez-Pavon, J. and Salvado, J. JHEP 1706 (2017) 112,[1704.08721]. • Looking for Axion Dark Matter in Dwarf Spheroidals [3] Caputo, A. and Garay, C. P and Witte, S.J. Phys.Rev. D 98 (2018) no.8, 083024,[1805.08780]. • Leptogenesis from oscillations and dark matter [4] Caputo, A. and Hernandez, P. and Rius, N. Eur.Phys.J. C 79 (2019) no.7, 574,[1807.03309]. • Detecting the Stimulated Decay of Axions at Radio Frequencies [5] Caputo, A. and Regis, M. and Taoso, M. and Witte, S. J. JCAP 1903 (2019) 027,[1811.08436]. • Searching for Sterile Neutrino with X-ray Intensity Mapping [6] Caputo, A. and Regis, M. and Taoso, M. Phys.Lett. B 100 (2019) no.11, 116007,[1911.09120]. • Minimal flavor violation in the see-saw portal [7] Barducci, D. and Bertuzzo, E. and Caputo, A. and Hernandez, P. JHEP 06 (2020) n.185,[2003.08391]. i The following are additional papers I worked on during my PhD but which slightly esulate from the main topics of my PhD research and are therefore not included as chapters. They are quoted as ordinary references when necessary. • Constraints on millicharged dark matter and axionlike particles from timing of radio waves [8] Caputo, A. and Sberna, L. and Frias, M. and Blas, D. and Pani, P. and Shao, L. and Yan, W. Phys.Rev. D 100 (2019) no.6, 063515, [1902.02695]. • Sub-MeV Dark Matter and the Goldstone Modes of Superfluid He- lium [9] Caputo, A. and Esposito, A. and Polosa, A. Phys.Rev. D 100 (2019) no.11, 116007,[1907.10635]. • Dark Matter, Dark Photon and Superfluid He-4 from Effective Field Theory [10] Caputo, A. and Esposito, A. and Geoffray, E. and Polosa, A. and Sun, S. Phys.Lett. B 100 (2019) no.11, 116007,[1911.04511]. • Binary pulsars as probes of a Galactic dark matter disk [11] Caputo, A. and Zavala, J.F and Blas, D. Phys. Dark Univ. 10 (2018) 1-11,[1709.03991]. • Cosmic implications of a low-scale solution to the axion domain wall problem [12] Caputo, A. and Reig, M. Phys. Rev. D100 (2018) no.6, 063530,[1905.13116]. • Radiative Axion Inflation [13] Caputo, A. Phys. Lett. B797 (2019) 134824,[1902.02666]. • No chiral light bending by clumps of axion-like particles [14] Blas, D. and Caputo, A. and Ivanov, M. and Sberna, L. Phys. Dark Univ. 27 (2019) 100428,[1910.06128]. • Gravitational-wave detection and parameter estimation for accreting black-hole binaries and their electromagnetic counterpart [15] ii Caputo, A. and Sberna, L. and Toubiana, A. and Babak, S. and Ba- rausse, E. and Marsat, S. and Pani, P. Phys. Dark Univ. 27 (2020) 100428,[2001.03620]. • Dark Photon Oscillations in Our Inhomogeneous Universe [16] Caputo, A. and Liu, H. and Mishra-Sharma, S. and Ruderman, J.T. [2002.05165 ]. • Modeling Dark Photon Oscillations in Our Inhomogeneous Universe [17] Caputo, A. and Liu, H. and Mishra-Sharma, S. and Ruderman, J.T. [2004.06733]. • Revisiting longitudinal plasmon-axion conversion in external magnetic fields [18] Caputo, A. and Millar, A. and Vitagliano, E. [2005.00078]. • Axion helioscopes as solar magnetometers [19] O’Hare, C.A.J. and Caputo, A. and Millar, A. and Vitagliano, E. [2006.10415]. • Exploring New Physics with O(keV) Electron Recoils in Direct Detec- tion Experiments [20] Bloch, I. M. and Caputo, A. and Essig, R. and Redigolo, D. and Shola- purkar, M. and Volansky, T. [2006.14521]. iii Preface In this doctoral thesis we have focused on different phenomenological and theoretical aspects of physics beyond the Standard Model. In par- ticular, we studied very well motivated extensions of the standard model which can explain light neutrino masses with the presence of heavy neu- tral leptons. We focused on the collider phenomenology of these models as well as on theoretical aspects related to their flavor symmetries. On the more cosmological side, we investigated minimal models that can explain neutrino masses, the matter-antimatter asymmetry as well as dark matter. Moreover, we also dedicated some effort to propose new direct and indirect searches for dark matter. This thesis is organized as follows: in the introductory Chapter 1 we provide a brief overview of the Standard Model. Then, In Chapter 2, we discuss some of the open problems in the Standard Model, highlighting in particular the original contributions presented in this thesis. El Chapter 3 consiste en un resumen detallado en español de los obje- tivos, motivación, metodología, resultados y conclusiones de esta tesis. Finally we present the original articles that consitute the body of this thesis. All papers have been maintained in their original published form. This implies there will be a certain amount of repetition between them and possibly sometimes different notations are used, however Chapter 2 provides the necessary introductory material and context to help reading each article as an independent entity. v Acknowledgements I cannot guarantee these acknowledgements will be original nor very well written, but for sure they will be sincere because I really feel super lucky to have many people I should thank. First of all, I want to thank my supervisor Pilar, who guided me into the world of physics, with passion and patience. One of the thing I admire more about Pilar is her curiosity and witness to learn always new things. I remember an entire week spent together studying Primordial Black Holes, a subject new for both of us, after attending a related seminar. I also thank her for all the help outside physics (better not to talk about my experience with my first house in Geneva..) and for being the best supervisor I could have wished, leaving me the freedom to do whatever I liked most, especially when I become independent and more interested to astro stuff. Then, I want to thank Diego Blas, who has been a second supervisor for me since our first chat at CERN when I was the mascot of the theory group. I was very lucky meeting you Diego, I think this changed my path quite a bit, in a way I like a lot! I am also very grateful to Antonello, who took me under his wing to have a lot of fun with dark matter, and especially to Angelo, from whom I learnt a lot and with whom is a real pleasure to work. I hope we will continue for a long time! I thank a lot Paolo, who gave me the opportunity to work on topics related to General Relativity, that I love, with enormous patience, allowing me to learn an enormous amount of new amazing things (and thanks for sharing your Mathematica Notebooks!). I am also very happy to thank Marco, for giving me the possibility to learn an astonishing amount of physics about dark matter and astroparti- cle, always having time for me, since the very beginning when we started checking some silly Mathematica bugs in my code when I was trying to reproduce his work about PBHs. vii I thank Sam, who is an amazing scientist and a good friend, who offered me the possibility to work with him and learn from him a lot, with our first project about axion decay, when I was a little bit stuck with other projects. A lot of people asked me how it has been possible to have so many papers during my Ph.D., the truth is that I have been very lucky, always having terrific collaborators. It is then a real pleasure to thanks Marija, Jordi and Jacobo, with whom I did my first papers (and thank you Jacobo for paying my last year!), as well as Nuria and Carlos. Then I want to thank the fantastic NYU crew, Hongwan, Josh and Sid, who taught me a lot, and with whom I still have so many other things to do. I thank Enrico and Alex, for all the work together, as well as Jesus, for the patience when we were trying to find dark matter with pulsars, and Misha. I thank Daniele and Enrico (Bertuzzo) for all the fun and cross-checks in our last work. I really thank also Marco R. in Turin, as well as Edoardo, for all the nights spent discussing crackpot physics, and Alex for all the hours spent cross-checking computations and Mathematica notebooks. I thank Mario, friend and collaborator, who gave me the possibility to learn about domain walls and other cool stuff, in a project which was a lot of fun and of which I am very proud of.
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