Galaxy Dark Matter: GalaxyGalaxy Lensing in the Hubble Deep Field
Abstract
In this Letter we present calibrated observations of the average mass of galaxies with 22 < I < 25 in the Hubble Deep Field. We measure the mean mass profile using the statistical gravitational lens distortion of faint blue background galaxies, based on 2221 foregroundbackground pairs. The observed weak lensing distortion is calibrated via full threedimensional simulations and other Hubble Space Telescope data on a foreground cluster of known mass. Inside a projected radius of 5" we find a 3 sigma detection of shear. Fitting to an isothermal mass distribution, we find a distortion of 0.066 ^{+0.018}_{0.019} at a radius of 2" (~8 h1 kpc). The (1 sigma ) limits on the parameters for the truncated isothermal model are sigma _{{v}} = 185 ^{+30}_{35} km s1, router >= 15 h1 kpc, and rcore = 0.6 ^{+1.3}_{0.6} h1 kpc. This corresponds to an average galaxy mass interior to 20 h1 kpc of 5.9 ^{+2.5}_{2.7} x 1011 h1 Msolar. Inside 10 h1 kpc, we find an average restframe Vband masstolight ratio of 11.4 ^{+6.0}_{6.7} h (M/LV)solar.
 Publication:

The Astrophysical Journal
 Pub Date:
 December 1996
 DOI:
 10.1086/310378
 arXiv:
 arXiv:astroph/9608043
 Bibcode:
 1996ApJ...473L..17D
 Keywords:

 DARK MATTER;
 GALAXIES: FUNDAMENTAL PARAMETERS;
 COSMOLOGY: GRAVITATIONAL LENSING;
 Astrophysics
 EPrint:
 11 pages with 3 encapsulated postscript figures, Submitted to ApJL