Near-term measurements with 21 cm intensity mapping: Neutral hydrogen fraction and BAO at z<2

Journal Article · Sat May 15 00:00:00 EDT 2010 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.81.103527· OSTI ID:21415187

Masui, Kiyoshi Wesley ^[1]; McDonald, Patrick; Pen, Ue-Li ^[1]

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1. Canadian Institute for Theoretical Astrophysics, 60 St. George Street Toronto, Ontario, M5S 3H8 (Canada)

It is shown that 21 cm intensity mapping could be used in the near term to make cosmologically useful measurements. Large scale structure could be detected using existing radio telescopes, or using prototypes for dedicated redshift survey telescopes. This would provide a measure of the mean neutral hydrogen density, using redshift space distortions to break the degeneracy with the linear bias. We find that with only 200 hours of observing time on the Green Bank Telescope, the neutral hydrogen density could be measured to 25% precision at redshift 0.54<z<1.09. This compares favorably to current measurements, uses independent techniques, and would settle the controversy over an important parameter that impacts galaxy formation studies. In addition, a 4000 hour survey would allow for the detection of baryon acoustic oscillations, giving a cosmological distance measure at 3.5% precision. These observation time requirements could be greatly reduced with the construction of multiple pixel receivers. Similar results are possible using prototypes for dedicated cylindrical telescopes on month time scales, or Square Kilometre Array pathfinder aperture arrays on day time scales. Such measurements promise to improve our understanding of these quantities while beating a path for future generations of hydrogen surveys.

• OSTI ID: 21415187
• Journal Information: Physical Review. D, Particles Fields, Vol. 81, Issue 10; Other Information: DOI: 10.1103/PhysRevD.81.103527; (c) 2010 The American Physical Society; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
BARYONS
COMPARATIVE EVALUATIONS
COSMIC RADIATION
COSMOLOGY
CYLINDRICAL CONFIGURATION
DENSITY
DETECTION
GALAXIES
HYDROGEN
OSCILLATIONS
RADIO TELESCOPES
RED SHIFT
SPACE
ANTENNAS
CONFIGURATION
ELECTRICAL EQUIPMENT
ELECTRONIC EQUIPMENT
ELEMENTARY PARTICLES
ELEMENTS
EQUIPMENT
EVALUATION
FERMIONS
HADRONS
IONIZING RADIATIONS
NONMETALS
PHYSICAL PROPERTIES
RADIATIONS
RADIO EQUIPMENT
TELESCOPES