iCosmo: an interactive cosmology package

¹ UMR 7158 (CNRS)/Service d’Astrophysique, AIM, CEA Saclay, 91191 Gif-sur-Yvette Cedex, France
e-mail: refregier@cea.fr
² Institute for Atronomy, ETH Hoenggerberg Campus, Physics Department, 8093 Zurich, Switzerland
³ Oxford Astrophysics, Department of Physics, Keble Road, Oxford, OX1 3RH, UK
⁴ SUPA, University of Edinburgh, Royal Observatory Edinburgh, EH9 3HJ, UK

Received: 8 October 2008
Accepted: 17 October 2010

Abstract

Aims. The interactive software package iCosmo, designed to perform cosmological calculations is described.

Methods. iCosmo is a software package to perfom interactive cosmological calculations for the low-redshift universe. Computing distance measures, the matter power spectrum, and the growth factor is supported for any values of the cosmological parameters. It also computes derived observed quantities for several cosmological probes such as cosmic shear, baryon acoustic oscillations, and type Ia supernovae. The associated errors for these observable quantities can be derived for customised surveys, or for pre-set values corresponding to current or planned instruments. The code also allows for calculation of cosmological forecasts with Fisher matrices, which can be manipulated to combine different surveys and cosmological probes. The code is written in the IDL language and thus benefits from the convenient interactive features and scientific libraries available in this language. iCosmo can also be used as an engine to perform cosmological calculations in batch mode, and forms a convenient adaptive platform for the development of further cosmological modules. With its extensive documentation, it may also serve as a useful resource for teaching and for newcomers to the field of cosmology.

Results. The iCosmo package is described with a number of examples and command sequences. The code is freely available with documentation at http://www.icosmo.org, along with an interactive web interface and is part of the Initiative for Cosmology, a common archive for cosmological resources.