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Cosmological weak lensing by the large scale structure of the Universe,cosmic shear, is coming of age as a powerful probe of the parameters describingthe cosmological model and matter power spectrum. It complements CMB studies,by breaking degeneracies and providing a cross-check. An important measure ofthe cosmic shear signal are the shear correlation functions; these can bedirectly calculated from data, and compared with theoretical expectations fordifferent cosmological models and matter power spectra. We present a MonteCarlo method to quickly simulate mock cosmic shear surveys. One application ofthis method is in the determination of the full covariance matrix for thecorrelation functions; this includes redshift binning and is applicable toarbitrary survey geometries. Terms arising from shot noise and cosmic variance(dominant on small and large scales respectively) are accounted for naturally.As an illustration of the use of such covariance matrices, we consider to whatdegree confidence regions on parameters are tightened when redshift binning isemployed. The parameters considered are those commonly discussed in cosmicshear analyses - the matter density parameter, dark energy density parameter(classical cosmological constant), power spectrum normalisation and shapeparameter. We incorporate our covariance matrices into a likelihood treatment,and also use the Fisher formalism to explore a larger region of parameter space(abridged).Comment: 14 pages, 8 figures, accepted by A&A corrected typos, some changes in  the discussion, shortened sections 2.1, 2.2 and 6.2.

The covariance of cosmic shear correlation functions and cosmological parameter estimates using redshift information