Deep Near Infrared Observations of the Field of z = 4.9 Quasar PC 1247+3406 with the Keck Telescope
Session 76 -- Keck
Oral presentation, Thursday, 2:30-4:00, Dwinelle 155 Room

## [76.05] Deep Near Infrared Observations of the Field of z = 4.9 Quasar PC 1247+3406 with the Keck Telescope

B.T.Soifer (Caltech), K.Matthews (Caltech), S.G.Djorgovski (Caltech), J.R.Graham (U.C.Berkeley), W.Harrison (CARA), G.Jernigan (U.C.Berkeley), J.Larkin, S.Lin (Caltech), J.Nelson (U.C.Berkeley), G.Neugebauer (Caltech), G.Smith (CARA), J.D.Smith, C.Ziomkowski (Caltech)

We present deep images of the field of the most distant object currently known, quasar PC 1247+3406 at $z = 4.897$, obtained using the near infrared camera on the Keck telescope. The images were obtained in the $K^{\prime\prime}$ ($\lambda_c \sim 2.15 ~\mu$m) filter, in $\sim 0.6^{\prime\prime}$ seeing, with $0.15^{\prime\prime}$ pixels. The limiting magnitude was $K^{\prime\prime}$ $> 20$ mag. A number of faint sources have been detected, some of which appear to be quite red in comparison to the deep, visible-light images obtained earlier at Palomar. In particular, an extremely red galaxy is seen within $3.6^{\prime\prime}$ NW of the quasar, i.e., $\sim 12 - 25 ~h^{-1}$ kpc in projection at the quasar redshift, for $\Omega_0 \sim 1 - 0$. It has a magnitude $K^{\prime\prime} = 19.4$, and colors $(i - K^{\prime\prime}) = 4.1$ and $(r - K^{\prime\prime}) > 5.5$. Its redshift is unknown at the present, but it may be a somewhat reddened actively star-forming young galaxy companion of the quasar itself. Further results on the multicolor photometry and counts of faint galaxies in the field will be presented.

\bf Acknowledgements \rm

The W.M. Keck Observatory is a scientific partnership between the California Institute of Technology and the University of California. It was made possible by the generous gift of the W.M. Keck foundation, and the support of its president, Howard Keck. We are most grateful for their visionary endowment that has made possible the first of the next generation of telescopes. It is a pleasure to also thank all of the many devoted people whose unflagging efforts have made possible the success of the W.M.Keck Observatory.