411 citations · 3.4k across the 64 of their papers we have counts for
60 papers · 1 filter
Axion Misalignment Across First-Order Phase Transitions
Galymzhan Baltabay, Francesco D'Eramo, Ville Vaskonen
When the axion mass is generated during a first-order phase transition and becomes non-vanishing only inside expanding true-vacuum bubbles, the standard picture of misalignment pro…
Cosmic-Ray Signatures of Annihilating and Semi-Annihilating Dark Matter via One-Step Cascades
Francesco D'Eramo, Silvia Manconi, Tommaso Sassi
We present a framework in which three classes of dark matter number-changing processes can affect both the relic abundance via thermal freeze-out in the early universe and the gene…
The COSMIC WISPers White Paper: The physics case for Weakly Interacting Slim Particles
Ariel Arza, Deniz Aybas, Shyam Balaji +124
Axions and other very weakly interacting slim particles (WISPs), with masses below 1 GeV, arise naturally in many extensions of the Standard Model of particle physics. In particula…
Axions at the meV Crossroads: Theory, Cosmology, Astrophysics, and Experiments
Michele Cicoli, Francesco D'Eramo, Luca Di Luzio +18
The meV mass range has emerged as a focal point in axion physics, where advances in theory, cosmology, astrophysics, and experimental techniques converge. Axions in this mass range…
Light to Heavy, Brief to Eternal: An Axion for Every Occasion (in the Early Universe)
Francesco D'Eramo
The early universe grants access to energy scales far beyond those achievable in terrestrial experiments and allows unstable Standard Model particles to play an active dynamical ro…
Ultralight Dark Matter from the Edge of Field Space
Mathias Becker, Francesco D'Eramo, Ville Vaskonen
We introduce a novel class of bosonic dark matter candidates that we dub wallions, featuring boundaries in field space. The wallion mass is exponentially suppressed when the separa…
Seasons of Dark Matter Freeze-In Shaped by the Weather of the Early Universe
Francesco D'Eramo, Alessandro Lenoci, Tommaso Sassi
Quantifying the imprints of freeze-in dark matter (DM) on cosmological structures requires knowledge of its phase-space distribution. We investigate how variations in the cosmologi…
Probing Non-Minimal Dark Sectors via the 21 cm Line at Cosmic Dawn
Federico Cima, Francesco D'Eramo
Observations of the hydrogen hyperfine transition through the 21 cm line near the end of the cosmic dark ages provide unique opportunities to probe new physics. In this work, we in…
Dark Matter Freeze-In and Small-Scale Observables: Novel Mass Bounds and Viable Particle Candidates
Francesco D'Eramo, Alessandro Lenoci, Ariane Dekker
The suppression of cosmological structure at small scales is a key signature of dark matter (DM) produced via freeze-in in the low-mass regime. We present a comprehensive analysis…
t-channel dark matter at the LHC -- a whitepaper
Chiara Arina, Benjamin Fuks, Luca Panizzi +67
This report, summarising work achieved in the context of the LHC Dark Matter Working Group, investigates the phenomenology of -channel dark matter models, spanning minimal setup…
Axion Portal to Scalar Dark Matter: Unveiling Stabilizing Symmetry Footprints
Francesco D'Eramo, Tommaso Sassi
We investigate the role of an axion-like particle (ALP) as a portal between the dark and visible sectors. Unlike conventional studies, which typically assume fermionic dark matter…
Back to the phase space: thermal axion dark radiation via couplings to standard model fermions
Francesco D'Eramo, Alessandro Lenoci
We investigate the cosmological consequences of axion interactions with standard model fermions accurately and precisely. Our analysis is entirely based on a phase space framework…
Irreducible cosmological backgrounds of a real scalar with a broken symmetry
Francesco D'Eramo, Andrea Tesi, Ville Vaskonen
We explore the irreducible cosmological implications of a singlet real scalar field. Our focus is on theories with an approximate and spontaneously broken symmetry w…
Dark Radiation from the Primordial Thermal Bath in Momentum Space
Francesco D'Eramo, Fazlollah Hajkarim, Alessandro Lenoci
Motivated by the stunning projections for future CMB surveys, we evaluate the amount of dark radiation produced in the early Universe by two-body decays or binary scatterings with…
Terrestrial detection of hidden vectors produced by solar nuclear reactions
Francesco D'Eramo, Giuseppe Lucente, Newton Nath +1
Solar nuclear reactions can occasionally produce sub-MeV elusive beyond the Standard Model particles that escape the solar interior without further interactions. This study focuses…
Axions in the Early Universe
Francesco D'Eramo
The Peccei-Quinn solution to the strong CP problem provides a motivated framework rich in cosmological consequence. Thermal axion production is unavoidable if there is a thermal ba…
Flavor Violating Axions in the Early Universe
Francesco D'Eramo, Seokhoon Yun
Flavor violating axion couplings can be in action before recombination, and they can fill the early universe with an additional radiation component. Working within a model-independ…
Thermal QCD Axions across Thresholds
Francesco D'Eramo, Fazlollah Hajkarim, Seokhoon Yun
Thermal axion production in the early universe goes through several mass thresholds, and the resulting rate may change dramatically across them. Focusing on the KSVZ and DFSZ frame…
Thermal axion production at low temperatures: a smooth treatment of the QCD phase transition
Francesco D'Eramo, Fazlollah Hajkarim, Seokhoon Yun
We study thermal axion production around the confinement scale. At higher temperatures, we extend current calculations to account for the masses of heavy quarks, whereas we quantif…
Displaced new physics at colliders and the early universe before its first second
Lorenzo Calibbi, Francesco D'Eramo, Sam Junius +2
Displaced vertices at colliders, arising from the production and decay of long-lived particles, probe dark matter candidates produced via freeze-in. If one assumes a standard cosmo…
Production of Thermal Axions across the ElectroWeak Phase Transition
Fernando Arias-Aragon, Francesco D'Eramo, Ricardo Z. Ferreira +2
Light axions can potentially leave a cosmic background, just like neutrinos. We complete the study of thermal axion production across the electroweak scale by providing a smooth an…
Leptoquarks and Real Singlets: A Richer Scalar Sector Behind the Origin of Dark Matter
Francesco D'Eramo, Nejc Košnik, Federico Pobbe +2
We investigate scenarios with scalar leptoquarks that act as portals between the Standard Model and Dark Matter. We assume that Dark Matter is a scal…
Lower Mass Bounds on FIMP Dark Matter Produced via Freeze-In
Francesco D'Eramo, Alessandro Lenoci
Feebly Interacting Massive Particles (FIMPs) are dark matter candidates that never thermalize in the early universe and whose production takes place via decays and/or scatterings o…
Cosmic Imprints of XENON1T Axions
Fernando Arias-Aragon, Francesco D'Eramo, Ricardo Z. Ferreira +2
The recent electron recoil excess observed by XENON1T has a possible interpretation in terms of solar axions coupled to electrons. If such axions are still relativistic at recombin…