English

Constraining the dark energy equation of state with double source plane strong lenses

Cosmology and Nongalactic Astrophysics 2015-06-04 v2 General Relativity and Quantum Cosmology

Abstract

We investigate the possibility of constraining the dark energy equation of state by measuring the ratio of Einstein radii in a strong gravitational lens system with two source planes. This quantity is independent of the Hubble parameter and directly measures the growth of angular diameter distances as a function of redshift. We investigate the prospects for a single double source plane system and for a forecast population of systems discovered by re-observing a population of single source lenses already known from a photometrically selected catalogue such as CASSOWARY or from a spectroscopically selected catalogue such as SLACS. We find that constraints comparable to current data-sets (15% uncertainty on the dark equation of state at 68%CL) are possible with a handful of double source plane systems. We also find that the method's degeneracy between Omega_M and w is almost orthogonal to that of CMB and BAO measurements, making this method highly complimentary to current probes.

Keywords

Cite

@article{arxiv.1203.2758,
  title  = {Constraining the dark energy equation of state with double source plane strong lenses},
  author = {Thomas E. Collett and Matthew W. Auger and Vasily Belokurov and Philip J. Marshall and Alex C. Hall},
  journal= {arXiv preprint arXiv:1203.2758},
  year   = {2015}
}

Comments

13 Pages