Please note that eDoc will be permanently shut down in the first quarter of 2021!      Home News About Us Contact Contributors Disclaimer Privacy Policy Help FAQ

Home
Search
Quick Search
Advanced
Fulltext
Browse
Collections
Persons
My eDoc
Session History
Login
Name:
Password:
Documentation
Help
Support Wiki
Direct access to
document ID:


          Institute: MPI für Astronomie     Collection: Publikationen_mpia     Display Documents



ID: 742560.0, MPI für Astronomie / Publikationen_mpia
Small-scale intensity mapping: Extended halos as a probe of the ionizing escape fraction and faint galaxy populations during reionization
Authors:Mas-Ribas, L.; Hennawi, J. F.; Dijkstra, M.; Davies, F. B.; Stern, J.; Rix, H.-W.
Date of Publication (YYYY-MM-DD):2017
Title of Journal:The Astrophysical Journal
Volume:846
Issue / Number:1
Start Page:id. 11 (9 pp)
Audience:Not Specified
Abstract / Description:We present a new method to quantify the value of the escape fraction of ionizing photons, and the existence of ultra-faint galaxies clustered around brighter objects during the epoch of cosmic reionization, using the diffuse Lyα, continuum, and Hα emission observed around galaxies at z∼ 6. We model the surface brightness profiles of the diffuse halos, considering the fluorescent emission powered by ionizing photons escaping from the central galaxies, and the nebular emission from satellite star-forming sources, by extending the formalisms developed in Mas-Ribas & Dijkstra and Mas-Ribas et al. The comparison between our predicted profiles and Lyα observations at z = 5.7 and z = 6.6 favors a low ionizing escape fraction, {f}{esc}{ion}∼ 5 % , for galaxies in the range -19≳ {M}{UV}≳ -21.5. However, uncertainties and possible systematics in the observations do not allow for firm conclusions. We predict Hα and rest-frame visible continuum observations with the James Webb Space Telescope (JWST), and show that it will be able to detect extended (a few tens of kiloparsecs) fluorescent Hα emission powered by ionizing photons escaping from a bright, L≳ 5{L}* , galaxy. Such observations could differentiate fluorescent emission from nebular emission by satellite sources. We discuss how observations and stacking several objects may provide unique constraints on the escape fraction for faint galaxies and/or the abundance of ultra-faint radiation sources.
Free Keywords:dark ages; reionization; first stars; galaxies: star formation; Galaxy: halo; radiative transfer
External Publication Status:published
Document Type:Article
Communicated by:N. N.
Affiliations:MPI für Astronomie
Identifiers:ISSN:0004-637X
URL:http://adsabs.harvard.edu/abs/2017ApJ...846...11M
The scope and number of records on eDoc is subject to the collection policies defined by each institute - see "info" button in the collection browse view.