Decaying Dark Matter: Simulations and Weak-Lensing Forecast

Abstract

Despite evidence for the existence of dark matter (DM) from very high and low redshifts, a moderate amount of DM particle decay remains a valid possibility. This includes both models with very long-lived yet unstable particles or mixed scenarios where only a small fraction of dark matter is allowed to decay. In this paper, we investigate how DM particles decaying into radiation affect non-linear structure formation. We look at the power spectrum and its redshift evolution, varying both the decay lifetime ($\tau$) and the fraction of decaying-to-total dark matter ($f$), and we propose a fitting function that reaches sub-percent precision below $k\sim 10$ h/Mpc. Based on this fit, we perform a forecast analysis for a Euclid-like weak lensing (WL) survey, including both massive neutrino and baryonic feedback parameters. We find that with WL observations alone, it is possible to rule out decay lifetimes smaller than $\tau =75$ Gyr (at 95 percent CL) for the case that all DM is unstable. This constraint improves to $\tau =182$ Gyr if the WL data is combined with CMB priors from the Planck satellite and to $\tau =275$ Gyr if we further assume baryonic feedback to be fully constrained by upcoming Sunyaev-Zeldovich or X-ray data. The latter shows a factor of 3.2 improvement compared to constraints from CMB data alone. Regarding the scenario of a strongly decaying sub-component of dark matter with $\tau \sim 30$ Gyr or lower, it will be possible to rule out a decaying-to-total fraction of $f>0.49$, $f>0.21$, and $f>0.13$ (at the 95 percent CL) for the same three scenarios. We conclude that the upcoming stage-IV WL surveys will allow us to significantly improve current constraints on the stability of the dark matter sector.

matching accepted version

References in corpus (46)

• The Cosmic Linear Anisotropy Solving System (CLASS) II: Approximation schemes
• The Baryon Oscillation Spectroscopic Survey of SDSS-III
• A 2.4% Determination of the Local Value of the Hubble Constant
• In the Realm of the Hubble tension $-$ a Review of Solutions
• Large Magellanic Cloud Cepheid Standards Provide a 1% Foundation for the Determination of the Hubble Constant and Stronger Evidence for Physics Beyond LambdaCDM
• Revising the Halofit Model for the Nonlinear Matter Power Spectrum
• Cosmology and Fundamental Physics with the Euclid Satellite
• Intrinsic alignment-lensing interference as a contaminant of cosmic shear
• Cosmology from cosmic shear power spectra with Subaru Hyper Suprime-Cam first-year data
• H0LiCOW V. New COSMOGRAIL time delays of HE0435-1223: $H_0$ to 3.8% precision from strong lensing in a flat $\Lambda$CDM model
• Dark Energy Survey Year 1 Results: Constraints on Extended Cosmological Models from Galaxy Clustering and Weak Lensing
• Massive Neutrinos and the Non-linear Matter Power Spectrum
• Neutrino masses and cosmology with Lyman-alpha forest power spectrum
• A new method to quantify the effects of baryons on the matter power spectrum
• A fresh look at linear cosmological constraints on a decaying dark matter component
• Late universe decaying dark matter can relieve the H_0 tension
• Quantifying baryon effects on the matter power spectrum and the weak lensing shear correlation
• Modelling baryonic feedback for survey cosmology
• Exploring the effects of galaxy formation on matter clustering through a library of simulation power spectra
• KiDS-1000 catalogue: Weak gravitational lensing shear measurements
• Alleviating the $H_0$ and ${\sigma }_8$ anomalies with a decaying dark matter model
• Strongest model-independent bound on the lifetime of Dark Matter
• Reconciling Planck results with low redshift astronomical measurements
• Constraining Dark Matter -- Dark Radiation interactions with CMB, BAO, and Lyman-$\alpha$
• Decaying dark matter and the tension in ${\sigma }_8$
• Dark matter component decaying after recombination: lensing constraints with Planck data
• Cosmological Simulations of Decaying Dark Matter: Implications for Small-scale Structure of Dark Matter Halos
• Baryonic effects for weak lensing. Part I. Power spectrum and covariance matrix
• WMAP Constraints on Decaying Cold Dark Matter
• The separate and combined effects of baryon physics and neutrino free-streaming on large-scale structure
• Cosmological constraints on late-universe decaying dark matter as a solution to the $H_0$ tension
• Dark-Matter Decays and Self-Gravitating Halos
• Toward an accurate mass function for precision cosmology
• Baryonic effects for weak lensing. Part II. Combination with X-ray data and extended cosmologies
• Warm Decaying Dark Matter and the Hubble Tension
• Late-time decaying dark matter: constraints and implications for the $H_0$-tension
• Mapping the allowed parameter space for decaying dark matter models
• Constraints on dark matter to dark radiation conversion in the late universe with DES-Y1 and external data
• Relativistic initial conditions for N-body simulations
• Mixed dark matter: matter power spectrum and halo mass function
• Cosmological Structure Formation in Decaying Dark Matter Models
• Constraints on decaying dark matter from weak lensing and cluster counts
• Formulation and constraints on decaying dark matter with finite mass daughter particles
• Weak Gravitational Lensing as a Method to Constrain Unstable Dark Matter
• On the degeneracy between baryon feedback and massive neutrinos as probed by matter clustering and weak lensing
• Fully relativistic treatment of decaying cold dark matter in $N$-body simulations

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