BEGIN:VCALENDAR VERSION:2.0 PRODID:-//linuxsoftware.nz//NONSGML Joyous v1.4//EN BEGIN:VEVENT SUMMARY:From Dark Sectors to the Axion-Neutrino Connection DTSTART:20251118T100000Z DTEND:20251118T120000Z DTSTAMP:20260923T225500Z UID:79bc4bb8-e9e0-4573-9c9f-729f05c5e6ba SEQUENCE:2 CREATED:20251114T094817Z DESCRIPTION:The Standard Model (SM) of particle physics provides a success ful description of fundamental particles and their interactions but fails to explain phenomena such as neutrino oscillations\, dark matter (DM)\, an d the baryon asymmetry of the Universe. These clear signs of physics beyon d the SM (BSM) motivate extensions introducing new particles and symmetrie s. Theoretical questions like the flavor puzzle – fermion masses and mix ing – and the strong charge-conjugation and parity (CP) problem further guide BSM frameworks. This thesis explores BSM scenarios based on two guid ing principles: constructing unified frameworks that address multiple open problems in (astro)particle physics and cosmology\, and emphasizing their experimental testability through detailed phenomenological analyses. This approach uncovers deep connections between seemingly disconnected sectors \, offering a more complete view of fundamental physics. We investigate da rk sector models for the origin of neutrino masses\, proposing a novel set up: the dark linear seesaw\, which radiatively links neutrino mass generat ion to viable DM candidates and predicts charged lepton flavor violation. In these scenarios\, dark sector particles can constitute weakly interacti ng massive particle (WIMP) DM\, testable via direct detection experiments. We study spontaneous CP violation induced by a complex scalar singlet\, a cting as a common origin of low- and high-energy CP violating effects rele vant for leptogenesis.We also analyze a Nelson-Barr model that solves the strong CP problem\, generates a realistic CKM matrix radiatively\, and yie lds scalar WIMP DM. Additionally\, we present unified axion frameworks in which a colored sector radiatively generates neutrino masses. These models predict distinctive axion couplings to photons and fermions and accommoda te axion DM in both pre- and post-inflationary cosmologies. Finally\, we e xplore minimal flavored Peccei-Quinn symmetries that link the flavor puzzl e\, neutrino masses and DM within a predictive and testable BSM framework. LAST-MODIFIED:20251114T094828Z LOCATION:Sala V1.01 (1º Piso do Pavilhão de Civil) do IST URL:http://df.vps.tecnico.ulisboa.pt/pt/eventos/from-dark-sectors-to-the-a xion-neutrino-connection/ X-ALT-DESC;FMTTYPE=text/html:

The Standard Model (SM) of particle physics provides a successful description of fundamental particles and their interactions but fails to explain phenomena such as ne utrino oscillations\, dark matter (DM)\, and the baryon asymmetry of the U niverse. These clear signs of physics beyond the SM (BSM) motivate extensi ons introducing new particles and symmetries. Theoretical questions like t he flavor puzzle – fermion masses and mixing – and the strong charge-c onjugation and parity (CP) problem further guide BSM frameworks.

This thesis explores BSM scenarios based on two guiding principles: const ructing unified frameworks that address multiple open problems in (astro)p article physics and cosmology\, and emphasizing their experimental testabi lity through detailed phenomenological analyses. This approach uncovers de ep connections between seemingly disconnected sectors\, offering a more co mplete view of fundamental physics.

We investigate dark sector m odels for the origin of neutrino masses\, proposing a novel setup: the dar k linear seesaw\, which radiatively links neutrino mass generation to viab le DM candidates and predicts charged lepton flavor violation. In these sc enarios\, dark sector particles can constitute weakly interacting massive particle (WIMP) DM\, testable via direct detection experiments. We study s pontaneous CP violation induced by a complex scalar singlet\, acting as a common origin of low- and high-energy CP violating effects relevant for le ptogenesis.

We also analyze a Nelson-Barr model that solves the s trong CP problem\, generates a realistic CKM matrix radiatively\, and yiel ds scalar WIMP DM. Additionally\, we present unified axion frameworks in w hich a colored sector radiatively generates neutrino masses. These models predict distinctive axion couplings to photons and fermions and accommodat e axion DM in both pre- and post-inflationary cosmologies. Finally\, we ex plore minimal flavored Peccei-Quinn symmetries that link the flavor puzzle \, neutrino masses and DM within a predictive and testable BSM framework.< /p> END:VEVENT END:VCALENDAR