Testing dark matter with high-redshift supernovae

Abstract

Dark matter in the Universe consisting of macroscopic objects such as primordial black holes may cause gravitational lensing of distant objects. The magnification associated with lensing will lead to additional scatter in the received flux from standard candles, and too small an observed scatter could rule out compact dark matter entirely. In this letter, we show how the scatter in fluxes of distant Type 1a supernovae could be used to distinguish between models with and without lensing by macroscopic dark matter. The proposed SNAP project, with $\sim 2400$ supernovae in the range $0.1\ls z\ls 1.7$, should be able to identify models at 99.9% confidence, if systematic errors are controlled. Note that this test is independent of any evolution of the mean supernova luminosity with redshift. The variances of the current Supernova Cosmology Project sample do not rule out compact lenses as dark matter: formally they favour such a population, but the significance is low, and removal of a single faint supernova from the sample reverses the conclusion.

5 pages, 6 figures, submitted to MNRAS. LaTeX reference error corrected

References in corpus (1)

• Cosmological implications of the MAXIMA-I high resolution Cosmic Microwave Background anisotropy measurement

Cited by in corpus (13)

• New Constraints on ${\Omega }_M$, ${\Omega }_{\Lambda }$, and w from an Independent Set of Eleven High-Redshift Supernovae Observed with HST
• Constraints on holographic dark energy from type Ia supernova observations
• Cosmological parameters from supernova observations: A critical comparison of three data sets
• Strong lensing optical depths in a \LambdaCDM universe
• Constraining dark matter halo properties using lensed SNLS supernovae
• Reducing distance errors for standard candles and standard sirens with weak-lensing shear and flexion maps
• The case for primordial black holes as dark matter
• Cosmological Microlensing Statistics: Variability rates for Quasars and GRB Afterglows, and implications for macrolensing magnification bias and flux ratios
• Constraining the primordial power spectrum from SNIa lensing dispersion
• Weighing dark matter haloes with gravitationally lensed supernovae
• Constraints on small-scale cosmological fluctuations from SNe lensing dispersion
• High-redshift microlensing and the spatial distribution of dark matter in the form of MACHOs
• Nanolensing of gamma-ray bursts