Search Publications
Figure of merit for dark energy constraints from current observational data
Wang, Yun
In order to make useful comparisons of different dark energy experiments, it is important to choose the appropriate figure of merit (FoM) for dark energy constraints. Here we show that for a set of dark energy parameters {fi}, it is most intuitive to define FoM=1/detCov(f1,f2,f3,…), where Cov(f1
γ-ray polarization constraints on Planck scale violations of special relativity
Ubertini, Pietro; Celotti, Annalisa; Maccione, Luca +2 more
Using recent polarimetric observations of the Crab Nebula in the hard X-ray band by INTEGRAL, we show that the absence of vacuum birefringence effects constrains O(E/M) Lorentz violation in QED to the level |ξ|<9×10-10 at 3σ CL, tightening by more than 3 orders of magnitude previous constraints. We show that planned X-ray polarimeter…
Search for cosmic strings in the Great Observatories Origins Deep Survey
Smoot, G. F.; Christiansen, J. L.; Albin, E. +3 more
We search Hubble Space Telescope Treasury Program images collected as part of the Great Observatories Origins Deep Survey for pairs of galaxies consistent with the gravitational lensing signature of a cosmic string. Our technique includes estimates of the efficiency for finding the lensed galaxy pair. In the north (south) survey field we find no e…