Keck Spectroscopy and High Resolution HST/UH 2.2m Imaging of Redshift z>4.5 Galaxies around Two Distant Quasars

Astronomy and Astrophysics – Astronomy

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Scientific paper

We report observations on redshift z>4.5 objects identified in deep narrow-band Lyman alpha imaging of the fields surrounding the quasars BR1202--0725 (z=4.695) and BR2237--0607 (z=4.558) and studied with followup spectroscopy with the LRIS spectrograph on Keck. Previous narrow-band imaging at the wavelength of redshifted Lyman alpha for BR1202--0725 identified emission which coincides with the continuum light from a faint galaxy seen in Hubble Space Telescope (HST) WFPC2 images 2.6'' NW of the quasar, and pointing radially towards it (Hu, McMahon, & Egami 1996, Ap. J., 459, L53--L55). From high resolution tip-tilt imaging (FWHM 0.45'') of this system at the UH 2.2m telescope in the Lyman alpha line, we identify a faint Lyman alpha emission component coincident with a second fainter galaxy 3'' SW of the quasar, also pointing radially towards the quasar in the HST image. This second emission system near the quasar at z=4.7 is confirmed in multi-slit LRIS spectra taken on these objects with the Keck 10m telescope. CIV emission is not detected in these spectra. For BR2237--0607 based on deep narrow-band Lyman alpha imaging followed by spectroscopy using LRIS at Keck, we identify two Lyman alpha emitting galaxies at z=4.55. In contrast to the BR1202--0725 emission-line objects, these galaxies have separations > 100'' ( ~ 700 kpc) from the quasar, which is unlikely to have a significant role in exciting them. Observed equivalent widths for the Lyman alpha line exceed 1000 Angstroms, in each case. While one of these objects is quite compact, and has no detectable continuum in a 1-hr I-band exposure at Keck, and thus might be an AGN, the second has a diffuse extended structure in both continuum and emission, and is probably a star-forming galaxy. Line fluxes are ~ 5x 10(-17) ergs cm(-2) s(-1) .

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Keck Spectroscopy and High Resolution HST/UH 2.2m Imaging of Redshift z>4.5 Galaxies around Two Distant Quasars does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Keck Spectroscopy and High Resolution HST/UH 2.2m Imaging of Redshift z>4.5 Galaxies around Two Distant Quasars, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Keck Spectroscopy and High Resolution HST/UH 2.2m Imaging of Redshift z>4.5 Galaxies around Two Distant Quasars will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1352363

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.