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The BTC40 Survey for Quasars at 4.8 < z < 6

E. M. Monier·J. D. Kennefick·P. B. Hall·P. S. Osmer·M. G. Smith·G. B. Dalton·R. F. Green
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Abstract

The BTC40 Survey for high-redshift quasars is a multicolor search using images obtained with the Big Throughput Camera (BTC) on the CTIO 4-m telescope in V, I, and z filters to search for quasars at redshifts of 4.8 < z < 6. The survey covers 40 sq. deg. in B, V, & I and 36 sq. deg. in z. Limiting magnitudes (3 sigma) reach to V = 24.6, I = 22.9 and z = 22.9. We used the (V-I) vs. (I-z) two-color diagram to select high-redshift quasar candidates from the objects classified as point sources in the imaging data. Follow-up spectroscopy with the AAT and CTIO 4-m telescopes of candidates having I < 21.5 has yielded two quasars with redshifts of z = 4.6 and z = 4.8 as well as four emission line galaxies with z = 0.6. Fainter candidates have been identified down to I = 22 for future spectroscopy on 8-m class telescopes.

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E. M. Monier, J. D. Kennefick, P. B. Hall, P. S. Osmer, M. G. Smith, G. B. Dalton, R. F. Green. 2002-09-03. The BTC40 Survey for Quasars at 4.8 < z < 6. https://doi.org/10.1086/344076

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