Lyalpha EMISSION FROM COSMIC STRUCTURE. I. FLUORESCENCE

Journal Article · Sun Jan 10 00:00:00 EST 2010 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/708/2/1048· OSTI ID:21392420

Kollmeier, Juna A ^[1]; Zheng, Zheng ^[2]; Dave, Romeel ^[3]; Gould, Andrew; Weinberg, David H ^[4]; Katz, Neal ^[5]; Miralda-Escude, Jordi ^[6]

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1. Observatories of the Carnegie Institution of Washington, 813 Santa Barbara Street, Pasadena, CA 91101 (United States)
2. Institute for Advanced Study, Einstein Drive, Princeton, NJ 08540 (United States)
3. Steward Observatory/TAP, University of Arizona, 933 N. Cherry Ave., Tucson, AZ 85721 (United States)
4. Department of Astronomy, Ohio State University, 140 W. 18th Ave., Columbus, OH 43210 (United States)
5. Department of Astronomy, University of Massachusetts, Amherst, MA 01003 (United States)
6. Institucio Catalana de Recerca i Estudis Avancats, Barcelona (Spain)

We present predictions for the fluorescent Lyalpha emission signature arising from photoionized, optically thick structures in smoothed particle hydrodynamic cosmological simulations of a LAMBDACDM universe using a Monte Carlo Lyalpha radiative transfer code. We calculate the expected Lyalpha image and two-dimensional spectra for gas exposed to a uniform ultraviolet ionizing background as well as gas exposed additionally to the photoionizing radiation from a local quasar, after correcting for the self-shielding of hydrogen. As a test of our numerical methods and for application to current observations, we examine simplified analytic structures that are uniformly or anisotropically illuminated. We compare these results with recent observations. We discuss future observing campaigns on large telescopes and realistic strategies for detecting fluorescence owing to the ambient metagalactic ionization and in regions close to bright quasars. While it will take hundreds of hours on the current generation of telescopes to detect fluorescence caused by the ultraviolet background alone, our calculations suggest that on the order of 10 sources of quasar-induced fluorescent Lyalpha emission should be detectable after a 10 hr exposure in a 10 arcmin{sup 2} field around a bright quasar. These observations will help probe the physical conditions in the densest regions of the intergalactic medium as well as the temporal light curves and isotropy of quasar radiation.

• OSTI ID: 21392420
• Journal Information: Astrophysical Journal, Vol. 708, Issue 2; Other Information: DOI: 10.1088/0004-637X/708/2/1048; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
COSMOLOGY
FLUORESCENCE
GALAXIES
HYDRODYNAMICS
HYDROGEN
MONTE CARLO METHOD
PHOTOIONIZATION
QUASARS
RADIANT HEAT TRANSFER
TELESCOPES
ULTRAVIOLET RADIATION
UNIVERSE
CALCULATION METHODS
COSMIC RADIO SOURCES
ELECTROMAGNETIC RADIATION
ELEMENTS
EMISSION
ENERGY TRANSFER
FLUID MECHANICS
HEAT TRANSFER
IONIZATION
LUMINESCENCE
MECHANICS
NONMETALS
PHOTON EMISSION
RADIATIONS