10 papers
A multi-axion model of inflation and dark matter
Marcos A. G. Garcia, Hansel Gordillo-Ruiz, Raul Henriquez-Ortiz +1
Models with extra dimensions include a tower of massive states that unavoidably contribute to cosmological dynamics. In particular, after compactification, a higher-dimensional axi…
Leptogenesis and Low Reheating Temperatures
Marcos A. G. Garcia, Stephen E. Henrich, Wenqi Ke +1
We study leptogenesis during non-instantaneous reheating in the canonical type-I seesaw framework, with the dominant source of right-handed neutrino (RHN) production being non-ther…
Gravitational Waves from Matter Perturbations of Spectator Scalar Fields
Marcos A. G. Garcia, Angel Garcia-Vega, Sarunas Verner
We compute the stochastic gravitational wave background sourced at second order by a spectator scalar field coupled to the inflaton through a portal interaction a…
Gravitational Waves from Isocurvature Perturbations of Spectator Scalar Fields
Marcos A. G. Garcia, Sarunas Verner
We present a mechanism for gravitational wave (GW) production from isocurvature perturbations in spectator scalar fields during inflation. These energetically subdominant fields de…
Constraints on Attractor Models of Inflation and Reheating from Planck, BICEP/Keck, ACT DR6, and SPT-3G Data
John Ellis, Marcos A. G. Garcia, Keith A. Olive +1
We analyze the latest cosmic microwave background (CMB) constraints on the scalar spectral index and tensor-to-scalar ratio from Planck 2018, BICEP/Keck 2018, the Atacama…
Gravitational Waves from Spectator Scalar Fields
Marcos A. G. Garcia, Sarunas Verner
We propose a novel mechanism for gravitational wave (GW) production sourced by spectator scalar fields during inflation. These fields, while not driving cosmic expansion, generate…
Scalar Field Fluctuations and the Production of Dark Matter
Marcos A. G. Garcia, Wenqi Ke, Yann Mambrini +2
One of the simplest possible candidates for dark matter is a stable scalar singlet beyond the Standard Model. If its mass is below the Hubble scale during inflation, long-wavelengt…
Inflaton Production of Scalar Dark Matter through Fluctuations and Scattering
Gongjun Choi, Marcos A. G. Garcia, Wenqi Ke +3
We study the effects on particle production of a Planck-suppressed coupling between the inflaton and a scalar dark matter candidate, . In the absence of this coupling, the domin…
Inflaton decay in No-Scale Supergravity and Starobinsky-like models
Yohei Ema, Marcos A. G. Garcia, Wenqi Ke +2
We consider the decay of the inflaton in Starobinsky-like models arising from either an theory of gravity or no-scale supergravity models. If Standard Model matter is…
Spectral distortions from promising single and multifield inflationary models
Alexander Baur, Marcos A. G. Garcia, Raul Henriquez-Ortiz +2
Forthcoming missions probing the absolute intensity of the CMB are expected to be able to measure spectral distortions, which are deviations from its blackbody distribution. As cos…