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Title: EXTENDED Ly{alpha} EMISSION AROUND STAR-FORMING GALAXIES

Abstract

Ly{alpha} photons that escape the interstellar medium of star-forming galaxies may be resonantly scattered by neutral hydrogen atoms in the circumgalactic and intergalactic media, thereby increasing the angular extent of the galaxy's Ly{alpha} emission. We present predictions of this extended, low surface brightness Ly{alpha} emission based on radiative transfer modeling in a cosmological reionization simulation. The extended emission can be detected from stacked narrowband images of Ly{alpha} emitters (LAEs) or of Lyman break galaxies (LBGs). Its average surface brightness profile has a central cusp, then flattens to an approximate plateau beginning at an inner characteristic scale below {approx}0.2 Mpc (comoving), then steepens again beyond an outer characteristic scale of {approx}1 Mpc. The inner scale marks the transition from scattered light of the central source to emission from clustered sources, while the outer scale marks the spatial extent of scattered emission from these clustered sources. Both scales tend to increase with halo mass, UV luminosity, and observed Ly{alpha} luminosity. The extended emission predicted by our simulation is already within reach of deep narrowband photometry using large ground-based telescopes. Such observations would test radiative transfer models of emission from LAEs and LBGs, and they would open a new window on the circumgalacticmore » environment of high-redshift star-forming galaxies.« less

Authors:
 [1];  [2];  [3];  [4];  [5]
  1. Yale Center For Astronomy and Astrophysics, Yale University, New Haven, CT 06520 (United States)
  2. Department of Astrophysical Sciences, Princeton University, Peyton Hall, Ivy Lane, Princeton, NJ 08544 (United States)
  3. Department of Astronomy, Ohio State University, Columbus, OH 43210 (United States)
  4. Department of Physics, Carnegie Mellon University, Pittsburgh, PA 15213 (United States)
  5. Institucio Catalana de Recerca i Estudis Avancats, Barcelona (Spain)
Publication Date:
OSTI Identifier:
21587491
Resource Type:
Journal Article
Journal Name:
Astrophysical Journal
Additional Journal Information:
Journal Volume: 739; Journal Issue: 2; Other Information: DOI: 10.1088/0004-637X/739/2/62; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0004-637X
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BRIGHTNESS; EMISSION; GALAXIES; LUMINOSITY; LYMAN LINES; RADIANT HEAT TRANSFER; RED SHIFT; SCATTERING; SIMULATION; ENERGY TRANSFER; HEAT TRANSFER; OPTICAL PROPERTIES; PHYSICAL PROPERTIES

Citation Formats

Zheng Zheng, Cen Renyue, Weinberg, David, Trac, Hy, and Miralda-Escude, Jordi, E-mail: zheng.zheng@yale.edu. EXTENDED Ly{alpha} EMISSION AROUND STAR-FORMING GALAXIES. United States: N. p., 2011. Web. doi:10.1088/0004-637X/739/2/62; COUNTRY OF INPUT: INTERNATIONAL ATOMIC ENERGY AGENCY (IAEA).
Zheng Zheng, Cen Renyue, Weinberg, David, Trac, Hy, & Miralda-Escude, Jordi, E-mail: zheng.zheng@yale.edu. EXTENDED Ly{alpha} EMISSION AROUND STAR-FORMING GALAXIES. United States. doi:10.1088/0004-637X/739/2/62; COUNTRY OF INPUT: INTERNATIONAL ATOMIC ENERGY AGENCY (IAEA).
Zheng Zheng, Cen Renyue, Weinberg, David, Trac, Hy, and Miralda-Escude, Jordi, E-mail: zheng.zheng@yale.edu. Sat . "EXTENDED Ly{alpha} EMISSION AROUND STAR-FORMING GALAXIES". United States. doi:10.1088/0004-637X/739/2/62; COUNTRY OF INPUT: INTERNATIONAL ATOMIC ENERGY AGENCY (IAEA).
@article{osti_21587491,
title = {EXTENDED Ly{alpha} EMISSION AROUND STAR-FORMING GALAXIES},
author = {Zheng Zheng and Cen Renyue and Weinberg, David and Trac, Hy and Miralda-Escude, Jordi, E-mail: zheng.zheng@yale.edu},
abstractNote = {Ly{alpha} photons that escape the interstellar medium of star-forming galaxies may be resonantly scattered by neutral hydrogen atoms in the circumgalactic and intergalactic media, thereby increasing the angular extent of the galaxy's Ly{alpha} emission. We present predictions of this extended, low surface brightness Ly{alpha} emission based on radiative transfer modeling in a cosmological reionization simulation. The extended emission can be detected from stacked narrowband images of Ly{alpha} emitters (LAEs) or of Lyman break galaxies (LBGs). Its average surface brightness profile has a central cusp, then flattens to an approximate plateau beginning at an inner characteristic scale below {approx}0.2 Mpc (comoving), then steepens again beyond an outer characteristic scale of {approx}1 Mpc. The inner scale marks the transition from scattered light of the central source to emission from clustered sources, while the outer scale marks the spatial extent of scattered emission from these clustered sources. Both scales tend to increase with halo mass, UV luminosity, and observed Ly{alpha} luminosity. The extended emission predicted by our simulation is already within reach of deep narrowband photometry using large ground-based telescopes. Such observations would test radiative transfer models of emission from LAEs and LBGs, and they would open a new window on the circumgalactic environment of high-redshift star-forming galaxies.},
doi = {10.1088/0004-637X/739/2/62; COUNTRY OF INPUT: INTERNATIONAL ATOMIC ENERGY AGENCY (IAEA)},
journal = {Astrophysical Journal},
issn = {0004-637X},
number = 2,
volume = 739,
place = {United States},
year = {2011},
month = {10}
}