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arXiv · astro-ph/9811115

Gravitational Lensing and the Hubble Deep Field

Asantha R. Cooray·Jean M. Quashnock·M. Coleman Miller
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Abstract

We calculate the expected number of multiply-imaged galaxies in the Hubble Deep Field (HDF), using photometric redshift information for galaxies with m_I < 27 that were detected in all four HDF passbands. A comparison of these expectations with the observed number of strongly lensed galaxies constrains the current value of Omega_m-Omega_Lambda, where Omega_m is the mean mass density of the universe and Omega_Lambda is the normalized cosmological constant. Based on current estimates of the HDF luminosity function and associated uncertainties in individual parameters, our 95% confidence lower limit on Omega_m-Omega_Lambda ranges between -0.44, if there are no strongly lensed galaxies in the HDF, and -0.73, if there are two strongly lensed galaxies in the HDF. If the only lensed galaxy in the HDF is the one presently viable candidate, then, in a flat universe (Omega_m+Omega_Lambda=1), Omega_Lambda < 0.79 (95% C.L.). These limits are compatible with estimates based on high-redshift supernovae and with previous limits based on gravitational lensing.

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Asantha R. Cooray, Jean M. Quashnock, M. Coleman Miller. 1998-11-07. Gravitational Lensing and the Hubble Deep Field. https://doi.org/10.1063/1.58600

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