1998/03/20 by Maki Suginohara, Tatsushi Suginohara, David N. Spergel · 4 citations
Physics and Astronomy · #Astrophysics and Cosmic Phenomena #Astrophysics and Star Formation Studies #Galaxies: Formation, Evolution, Phenomena #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1086/306787
15 pages, 1 postscript figures included; Uses aaspp4.sty (AASTeX v4.0); Submitted to The Astrophysical Journal
arxiv created 1998/03/20 · openalex publication_date 1998/03/20 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
By redshift of 10, star formation in the first objects should have produced considerable amounts of Carbon, Nitrogen and Oxygen. The submillimeter lines of C, N and O redshift into the millimeter and centimeter bands (0.5 mm -- 1.2 cm), where they may be detectable. High spectral resolution observations could potentially detect inhomogeneities in C, N and O emission, and see the first objects forming at high redshift. We calculate expected intensity fluctuations and discuss frequency and angular resolution required to detect them. For CII emission, we estimate the intensity using two independent methods: the line emission coefficient argument and the luminosity density argument. We find they are in good agreement. At 1+z ∼ 10, the typical protogalaxy has a velocity dispersion of 30 km s-1 and angular size of 1 arcsecond. If CII is the dominant coolant, then we estimate a characteristic line strength of ∼ 0.1 K km s-1. We also discuss other atomic lines and estimate their signal. Observations with angular resolution of 10-3 can detect moderately nonlinear fluctuations of amplitude 2 ⋅ 10-5 times the microwave background. If the intensity fluctuations are detected, they will probe matter density inhomogeneity, chemical evolution and ionization history at high redshifts.