Details

Autor(en) / Beteiligte

• Jones, L. H.
• Barger, A. J.
• Cowie, L. L.
• Oesch, P.
• Hu, E. M.
• Songaila, A.
• Naidu, R. P.

Titel

z ∼ 2.5-3 Ionizers in the GOODS-N Field

Ist Teil von

• The Astrophysical journal, 2018-08, Vol.862 (2), p.142

Ort / Verlag

Philadelphia: The American Astronomical Society

Erscheinungsjahr

2018

Link zum Volltext

Quelle

Elektronische Zeitschriftenbibliothek - Frei zugängliche E-Journals

Beschreibungen/Notizen

• We use deep F275W imaging from the Hubble Deep UV Legacy Survey (HDUV) and G280 grism spectroscopy from the Hubble Space Telescope/WFC3, along with new and archival optical spectra from Keck/DEIMOS, to search for candidate ionizing sources in the GOODS-N field at z ∼ 2.5-3. Spectroscopic identification of our UV-selected sources are 99% complete to F275W = 25.5 in the region of the UV imaging, and we identify six potential ionizing galaxies or active galactic nuclei (AGNs) at z ∼ 3. By far the brightest of these is a z = 2.583 AGN that totally dominates the ionizing flux in the region, with a specific ionizing volume emissivity at 912 of erg s−1 Hz−1 Mpc−3. Based on our spectroscopic data, we find that four candidates are contaminated by foreground galaxies at z ∼ 0.5-0.7. At erg s−1 Hz−1 Mpc−3, the remaining candidate galaxy's contribution to the ionizing background lies well below the flux required to ionize the intergalactic medium at z ∼ 2.5-3, consistent with previous observations that show that AGNs provide the bulk of the ionizing background at these redshifts.