Shadows of Galaxy Haloes

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Session 119 -- Galaxies and Clusters of Galaxies, X-Ray Observationsd
Oral presentation, Thursday, 12, 1995, 2:00pm - 3:30pm

[119.07] Shadows of Galaxy Haloes

R.G. Clowes, L.E. Campusano, J. Melnick (Centre for Astrophysics, University of Central Lancashire)

Ultradeep imaging (to $V \sim 28$) with the ESO 3.5~m NTT has shown that the two brightest galaxies ($V \sim 18$) in a 7.6~arcmin field at high galactic latitude are surrounded by ``dark haloes'' of diameter $\sim 180h^{-1}$~kpc. These dark haloes appear to be regions in which the background light from beyond the galaxies has been reduced by obscuration. Thus we appear to be seeing the shadows of the haloes of these galaxies. The size of the effect is not large, being a reduction in the total background (i.e.\ including the local sky background) of only $\sim$ 0.06\%. Both galaxies appear to be ellipticals at the same redshift $z = 0.191$, separated on the sky by $\sim 400h^{-1}$~kpc. Dusty haloes of similar size, diameter $\sim 90h^{-1}$~kpc, have recently been reported by Zaritsky (1994), from the reddening of background galaxies.

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