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Title: Measuring the 3D clustering of undetected galaxies through cross correlation of their cumulative flux fluctuations from multiple spectral lines

Abstract

We discuss a method for detecting the emission from high redshift galaxies by cross correlating flux fluctuations from multiple spectral lines. If one can fit and subtract away the continuum emission with a smooth function of frequency, the remaining signal contains fluctuations of flux with frequency and angle from line emitting galaxies. Over a particular small range of observed frequencies, these fluctuations will originate from sources corresponding to a series of different redshifts, one for each emission line. It is possible to statistically isolate the fluctuations at a particular redshift by cross correlating emission originating from the same redshift, but in different emission lines. This technique will allow detection of clustering fluctuations from the faintest galaxies which individually cannot be detected, but which contribute substantially to the total signal due to their large numbers. We describe these fluctuations quantitatively through the line cross power spectrum. As an example of a particular application of this technique, we calculate the signal-to-noise ratio for a measurement of the cross power spectrum of the OI(63 μm) and OIII(52 μm) fine structure lines with the proposed Space Infrared Telescope for Cosmology and Astrophysics (SPICA). We find that the cross power spectrum can be measured beyondmore » a redshift of z = 8. Such observations could constrain the evolution of the metallicity, bias, and duty cycle of faint galaxies at high redshifts and may also be sensitive to the reionization history through its effect on the minimum mass of galaxies. As another example of this technique, we calculate the signal-to-noise ratio for the cross power spectrum of CO line emission measured with a large ground based telescope like the Cornell Caltech Atacama Telescope (CCAT) and 21-cm radiation originating from hydrogen in galaxies after reionization with an interferometer similar in scale to the Murchison Widefield Array (MWA), but optimized for post-reionization redshifts.« less

Authors:
 [1];  [2]
  1. Jefferson Laboratory of Physics, Harvard University, Cambridge, MA 02138 (United States)
  2. Harvard-Smithsonian CfA, 60 Garden Street, Cambridge, MA 02138 (United States)
Publication Date:
OSTI Identifier:
22275377
Resource Type:
Journal Article
Journal Name:
Journal of Cosmology and Astroparticle Physics
Additional Journal Information:
Journal Volume: 2010; Journal Issue: 11; Other Information: Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 1475-7516
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ASTROPHYSICS; CARBON MONOXIDE; CORRELATIONS; COSMOLOGY; ENERGY SPECTRA; FINE STRUCTURE; FLUCTUATIONS; FREQUENCY DEPENDENCE; GALAXIES; GALAXY CLUSTERS; HYDROGEN; OXYGEN IONS; RED SHIFT; SIGNAL-TO-NOISE RATIO

Citation Formats

Visbal, Eli, and Loeb, Abraham. Measuring the 3D clustering of undetected galaxies through cross correlation of their cumulative flux fluctuations from multiple spectral lines. United States: N. p., 2010. Web. doi:10.1088/1475-7516/2010/11/016.
Visbal, Eli, & Loeb, Abraham. Measuring the 3D clustering of undetected galaxies through cross correlation of their cumulative flux fluctuations from multiple spectral lines. United States. https://doi.org/10.1088/1475-7516/2010/11/016
Visbal, Eli, and Loeb, Abraham. 2010. "Measuring the 3D clustering of undetected galaxies through cross correlation of their cumulative flux fluctuations from multiple spectral lines". United States. https://doi.org/10.1088/1475-7516/2010/11/016.
@article{osti_22275377,
title = {Measuring the 3D clustering of undetected galaxies through cross correlation of their cumulative flux fluctuations from multiple spectral lines},
author = {Visbal, Eli and Loeb, Abraham},
abstractNote = {We discuss a method for detecting the emission from high redshift galaxies by cross correlating flux fluctuations from multiple spectral lines. If one can fit and subtract away the continuum emission with a smooth function of frequency, the remaining signal contains fluctuations of flux with frequency and angle from line emitting galaxies. Over a particular small range of observed frequencies, these fluctuations will originate from sources corresponding to a series of different redshifts, one for each emission line. It is possible to statistically isolate the fluctuations at a particular redshift by cross correlating emission originating from the same redshift, but in different emission lines. This technique will allow detection of clustering fluctuations from the faintest galaxies which individually cannot be detected, but which contribute substantially to the total signal due to their large numbers. We describe these fluctuations quantitatively through the line cross power spectrum. As an example of a particular application of this technique, we calculate the signal-to-noise ratio for a measurement of the cross power spectrum of the OI(63 μm) and OIII(52 μm) fine structure lines with the proposed Space Infrared Telescope for Cosmology and Astrophysics (SPICA). We find that the cross power spectrum can be measured beyond a redshift of z = 8. Such observations could constrain the evolution of the metallicity, bias, and duty cycle of faint galaxies at high redshifts and may also be sensitive to the reionization history through its effect on the minimum mass of galaxies. As another example of this technique, we calculate the signal-to-noise ratio for the cross power spectrum of CO line emission measured with a large ground based telescope like the Cornell Caltech Atacama Telescope (CCAT) and 21-cm radiation originating from hydrogen in galaxies after reionization with an interferometer similar in scale to the Murchison Widefield Array (MWA), but optimized for post-reionization redshifts.},
doi = {10.1088/1475-7516/2010/11/016},
url = {https://www.osti.gov/biblio/22275377}, journal = {Journal of Cosmology and Astroparticle Physics},
issn = {1475-7516},
number = 11,
volume = 2010,
place = {United States},
year = {Mon Nov 01 00:00:00 EDT 2010},
month = {Mon Nov 01 00:00:00 EDT 2010}
}