Narrowband imaging of Escaping Lyman-Continuum Emission in the SSA22 Field

Details Narrowband imaging of Escaping Lyman-Continuum Emission in the SSA22 Field Narrowband imaging of Escaping Lyman-Continuum Emission in the SSA22 Field

2011-02-01

arxiv.org/abs/1102.0286v2

Astronomy and Astrophysics

Astrophysics

Cosmology and Extragalactic Astrophysics

30 pages, 15 figures; Accepted for publication by ApJ

Scientific paper

We present the results of an ultradeep, narrowband imaging survey for Lyman-continuum (LyC) emission at z~3 in the SSA22a field. We employ a custom narrowband filter centered at 3640A (NB3640), which probes the LyC region for galaxies at z>3.06. We also analyze new and archival NB4980 imaging tuned to the wavelength of the Lya emission line at z=3.09, and archival broadband B, V, and R images of the non-ionizing UV continuum. Our NB3640 images contain 26 z>3.06 Lyman Break Galaxies (LBGs) as well as a set of 130 Lya emitters (LAEs), identified by their excess NB4980 flux relative to the BV continuum. Six LBGs and 28 LAEs are detected in the NB3640 image. LBGs appear to span a range of NB3640-R colors, while LAEs appear bimodal in their NB3640-R properties. We estimate average UV to LyC flux density ratios, corrected for foreground contamination and intergalactic medium absorption, finding ^{LBG} = 11.3^{+10.3}_{-5.4}, which implies a LBG LyC escape fraction f_{esc}^{LyC} ~ 0.1, and ^{LAE} = 2.2^{+0.9}_{-0.6}. The strikingly blue LAE flux density ratios defy interpretation in terms of standard stellar population models. Assuming ^{LBG} applies down to L=0.1L*, we estimate a galaxy contribution to the intergalactic hydrogen ionization rate that is consistent with independent estimates based on the Lya forest opacity at z~3. If we assume that ^{LAE} holds at the faintest luminosities, the galaxy contribution significantly exceeds that inferred from the Lya forest. Further follow-up study of these faint LAEs is crucial, given the potentially important contribution similar objects make to the process of reionization. (Abridged)

Affiliated with

Also associated with

No associations

Rating

Narrowband imaging of Escaping Lyman-Continuum Emission in the SSA22 Field 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 Narrowband imaging of Escaping Lyman-Continuum Emission in the SSA22 Field, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Narrowband imaging of Escaping Lyman-Continuum Emission in the SSA22 Field will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-79170