about the calculator

This calculator determines the dark energy figure of merit, defined as 1/(σwaσwp) (see DETF report), as well as the expected cluster counts, for a large cluster survey, with several user-specified parameters. It assumes either a single observable-mass relation with self-calibration or two different observable-mass relations with cross-calibration.

Additionally, the calculator optimizes follow ups to a large cluster survey using a simulated annealing algorithm, as described in Wu, Rozo, and Wechsler 2009 (W09).

underlying assumptions

conditions of use

This is a pre-release version. It may be used pre-release (with no guarantees!) if users:


There are two versions of the calculator.

The calculators run calculations on the client's computer, and require Java SE5 (or later) to run. If your computer downloads the file but does not open it, try running the following from the command line:
Cluster Single:
javaws http://risa.stanford.edu/cluster/FisherCalculator_JavaSE5.jnlp
Cluster Cross-Calibrating:
javaws http://risa.stanford.edu/cluster/FisherCalculator_JavaSE5_cross.jnlp

comments and suggestions

are encouraged! Please email cluster-calc@lists.stanford.edu. Current planned improvements include:


CLUSTER was developed by Adam Bouland, Hao-Yi Wu, and Risa Wechsler, with support from Stanford University.

Creative Commons License