Vector dark matter production during inflation in the gradient-expansion formalism

Abstract

A massive vector field is a highly promising candidate for dark matter in the Universe. A salient property of dark matter is its negligible or null coupling to ordinary matter, with the exception of gravitational interaction. This poses a significant challenge in producing the requisite amount of dark particles through processes within the Standard Model. In this study, we examine the production of a vector field during inflation due to its direct interaction with the inflaton field through kinetic and axionlike couplings as well as the field-dependent mass. The gradient-expansion formalism, previously proposed for massless Abelian gauge fields, is extended to include the longitudinal polarization of a massive vector field. We derive a coupled system of equations of motion for a set of bilinear functions of the vector field. This enables us to address the nonlinear dynamics of inflationary vector field production, including backreaction on background evolution. To illustrate this point, we apply our general formalism to a low-mass vector field whose kinetic and mass terms are coupled to the inflaton via the Ratra-type exponential function. The present study investigates the production of its transverse and longitudinal polarization components in a benchmark inflationary model with a quadratic inflaton potential. It has been demonstrated that pure mass coupling is able to enhance only the longitudinal components. By turning on also the kinetic coupling, one can get different scenarios. As the coupling function decreases, the primary contribution to the energy density is derived from the transverse polarizations of the vector field. Conversely, for an increasing coupling function, the longitudinal component becomes increasingly significant and rapidly propels the system into the strong backreaction regime.

17 pages, 6 figures

References in corpus (54)

• Particle Dark Matter: Evidence, Candidates and Constraints
• Planck 2018 results. X. Constraints on inflation
• A History of Dark Matter
• Modified Newtonian Dynamics (MOND): Observational Phenomenology and Relativistic Extensions
• WISPy Cold Dark Matter
• The $\nu$MSM, Dark Matter and Neutrino Masses
• Cosmological Magnetic Fields: Their Generation, Evolution and Observation
• Primordial Black Holes as Dark Matter: Recent Developments
• A facility to Search for Hidden Particles at the CERN SPS: the SHiP physics case
• WIMP dark matter candidates and searches - current status and future prospects
• Physics Beyond Colliders at CERN: Beyond the Standard Model Working Group Report
• The origin, evolution and signatures of primordial magnetic fields
• Vector Dark Matter from Inflationary Fluctuations
• Dark Light, Dark Matter and the Misalignment Mechanism
• The Dark Photon
• Dark matter and the early Universe: a review
• Dark photon limits: a handbook
• Cosmological Constraints on Bose-Einstein-Condensed Scalar Field Dark Matter
• Vector dark matter production at the end of inflation
• Gravitational probes of dark matter physics
• Production of Purely Gravitational Dark Matter: The Case of Fermion and Vector Boson
• Instability of the ACW model, and problems with massive vectors during inflation
• Gravitational production of vector dark matter
• Inflationary Magnetogenesis without the Strong Coupling Problem
• Completely Dark Photons from Gravitational Particle Production During Inflation
• The Cosmological Evolution of Light Dark Photon Dark Matter
• Gauge-field production during axion inflation in the gradient expansion formalism
• Challenges in Inflationary Magnetogenesis: Constraints from Strong Coupling, Backreaction and the Schwinger Effect
• The generation of helical magnetic field in a viable scenario of Inflationary Magnetogenesis
• Curvature Perturbations in Anisotropic Inflation with Symmetry Breaking
• Light Dark Photon Dark Matter from Inflation
• Inflation from Charged Scalar and Primordial Magnetic Fields?
• Gravitational production of dark photon dark matter with mass generated by the Higgs mechanism
• Vector dark matter production from inflation with symmetry breaking
• On the health of a vector field with (R A^2)/6 coupling to gravity
• Constraint on Vector Coherent Oscillation Dark Matter with Kinetic Function
• Dark Photon Dark Matter without Stueckelberg Mass
• Axion inflation in the strong-backreaction regime: decay of the Anber-Sorbo solution
• Backreaction from gauge fields produced during inflation
• Recent Progress in Search for Dark Sector Signatures
• Parity violating gravitational waves at the end of inflation
• Magnetogenesis in Higgs-Starobinsky inflation
• The $Z_7$ model of three-component scalar dark matter
• Runaway Gravitational Production of Dark Photons
• Dark photon dark matter from charged inflaton
• Unifying dark matter, dark energy and inflation with a fuzzy dark fluid
• Magnetogenesis by non-minimal coupling to gravity in the Starobinsky inflationary model
• Detectable and defect-free dark photon dark matter
• Experimental targets for dark photon dark matter
• On the Schwinger effect during axion inflation
• Gradient expansion formalism for magnetogenesis in the kinetic coupling model
• Chirality production during axion inflation
• Generation of an electromagnetic field nonminimally coupled to gravity during Higgs inflation
• Inflationary magnetogenesis: solving the strong coupling and its non-Gaussian signatures