235 citations · 3.5k across the 78 of their papers we have counts for
Showing 1999Show all
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astro-ph1999★ 67 cited
X-ray variability in a deep, flux limited sample of QSOs
O. Almaini, A. Lawrence, T. Shanks +6
We present an analysis of X-ray variability in a flux limited sample of QSOs. Selected from our deep ROSAT survey, these QSOs span a wide range in redshift () and are ty…
astro-ph1999★ 28 cited
Statistical lensing of faint QSOs by galaxy clusters
S. M. Croom, T. Shanks
We investigate the anti-correlation between faint high redshift QSOs and low redshift galaxy groups found by Boyle, Fong & Shanks (1988), on the assumption that it is caused by gra…
astro-ph1999★ 15 cited
Faint UBVRI CCD sequences for wide-field surveys -- II. UBVR sequences at declination=-30 deg
Scott M. Croom, A. Ratcliffe, Q. A. Parker +3
We present results from a continuing campaign to secure deep multi-colour CCD sequences for photometric calibration in UK Schmidt fields with galactic latitudes |b|>50deg. In this…