5 research outputs found
Detecting z > 10 objects through carbon, nitrogen and oxygen emission lines
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 \sim 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 \sim 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 \cdot 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.Comment: 15 pages, 1 postscript figures included; Uses aaspp4.sty (AASTeX
v4.0); Submitted to The Astrophysical Journa
Cross-Correlating Cosmic Microwave Background Radiation Fluctuations with Redshift Surveys: Detecting the Signature of Gravitational Lensing
Density inhomogeneities along the line-of-sight distort fluctuations in the
cosmic microwave background. Usually, this effect is thought of as a small
second-order effect that mildly alters the statistics of the microwave
background fluctuations. We show that there is a first-order effect that is
potentially observable if we combine microwave background maps with large
redshift surveys. We introduce a new quantity that measures this lensing
effect, , where T is the microwave
background temperature and is the lensing due to matter in the
region probed by the redshift survey. We show that the expected signal is first
order in the gravitational lensing bending angle, , and find that it should be easily detectable, (S/N) 15-35, if
we combine the Microwave Anisotropy Probe satellite and Sloan Digital Sky
Survey data. Measurements of this cross-correlation will directly probe the
``bias'' factor, the relationship between fluctuations in mass and fluctuations
in galaxy counts.Comment: 13 pages, 4 postscript figures included; Uses aaspp4.sty (AASTeX
v4.0); Accepted for publication in Astrophysical Journal, Part
Cross-Correlating Cosmic Microwave Background Radiation Fluctuations with Redshift Surveys: Detecting the Signature of Gravitational Lensing
Density inhomogeneities along the line-of-sight distort fluctuations in the cosmic microwave background. Usually, this effect is thought of as a small second-order effect that mildly alters the statistics of the microwave background fluctuations. We show that there is a first-order effect that is potentially observable if we combine microwave background maps with large redshift surveys. We introduce a new quantity that measures this lensing effect, ! T (ffi` \Delta rT ) ?; where T is the microwave background temperature and ffi ` is the lensing due to matter in the region probed by the redshift survey. We show that the expected signal is first order in the gravitational lensing bending angle, ! (ffi`) 2 ? 1=2 ; and find that it should be easily detectable, (S/N)¸ 15 \Gamma 35; if we combine the Microwave Anisotropy Probe satellite and Sloan Digital Sky Survey data. Measurements of this cross-correlation will directly probe the "bias" factor, the relationship between fluctuations in..
POPe-752, UTAP-285
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 \Gamma1 and angular size of 1 arcsecond. If CII is the dominant coolant, then we estimate a characteristic line strength of ¸ 0:1 Kkm s \Gamma1 . We also discuss other atomic lines and estimate thei..