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Revisiting the Magnification of Type Ia Supernovae with SDSS

Brice Ménard·Neal Dalal
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Abstract

We cross-correlate the sample of Type Ia supernovae from Riess et al. (2004) with the SDSS DR2 photometric galaxy catalogue. In contrast to recent work, we find no detectable correlation between supernova magnitude and galaxy overdensity on scales ranging between 1 and 10 arcminutes. Our results are in accord with theoretical expectations for gravitational lensing of supernovae by large-scale structure. Future supernova surveys like SNAP will be capable of detecting unambiguously the predicted lensing signal.

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Brice Ménard, Neal Dalal. 2004-07-01. Revisiting the Magnification of Type Ia Supernovae with SDSS. https://doi.org/10.1111/j.1365-2966.2005.08764.x

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