# Cosmological-parameter determination with microwave background maps

## Abstract

The angular power spectrum of the cosmic microwave background (CMB) contains information on virtually all cosmological parameters of interest, including the geometry of the Universe ({Omega}), the baryon density, the Hubble constant ({ital h}), the cosmological constant ({Lambda}), the number of light neutrinos, the ionization history, and the amplitudes and spectral indices of the primordial scalar and tensor perturbation spectra. We review the imprint of each parameter on the CMB. Assuming only that the primordial perturbations were adiabatic, we use a covariance-matrix approach to estimate the precision with which these parameters can be determined by a CMB temperature map as a function of the fraction of sky mapped, the level of pixel noise, and the angular resolution. For example, with no prior information about any of the cosmological parameters, a full-sky CMB map with 0.5{degree} angular resolution and a noise level of 15 {mu}K per pixel can determine {Omega}, {ital h}, and {Lambda} with standard errors of {plus_minus}0.1 or better, and provide determinations of other parameters which are inaccessible with traditional observations. Smaller beam sizes or prior information on some of the other parameters from other observations improves the sensitivity. The dependence on the underlying cosmological model is discussed. {copyright}more »

- Authors:

- Department of Physics, Syracuse University, Syracuse, New York 13244 (United States)
- Department of Physics, Columbia University, New York, New York 10027 (United States)
- Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, Massachusetts 02138 (United States)|[Department of Physics, Lyman Laboratory, Harvard University, Cambridge, Massachusetts 02138 (United States)
- Department of Astrophysical Sciences, Princeton University, Princeton, New Jersey 08544 (United States)|[Department of Astronomy, University of Maryland, College Park, Maryland 20742 (United States)

- Publication Date:

- Research Org.:
- Syracuse University

- OSTI Identifier:
- 286228

- DOE Contract Number:
- FG02-85ER40231; FG02-92ER40699

- Resource Type:
- Journal Article

- Journal Name:
- Physical Review, D

- Additional Journal Information:
- Journal Volume: 54; Journal Issue: 2; Other Information: PBD: Jul 1996

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 66 PHYSICS; MICROWAVE RADIATION; SPECTRA; BACKGROUND RADIATION; COSMOLOGICAL CONSTANT; MAPS; UNIVERSE; GEOMETRY; BARYONS; DENSITY; NEUTRINOS; IONIZATION; AMPLITUDES; NOISE; SENSITIVITY; COSMOLOGICAL MODELS; HUBBLE CONSTANT

### Citation Formats

```
Jungman, G., Kamionkowski, M., Kosowsky, A., and Spergel, D.N.
```*Cosmological-parameter determination with microwave background maps*. United States: N. p., 1996.
Web. doi:10.1103/PhysRevD.54.1332.

```
Jungman, G., Kamionkowski, M., Kosowsky, A., & Spergel, D.N.
```*Cosmological-parameter determination with microwave background maps*. United States. doi:10.1103/PhysRevD.54.1332.

```
Jungman, G., Kamionkowski, M., Kosowsky, A., and Spergel, D.N. Mon .
"Cosmological-parameter determination with microwave background maps". United States. doi:10.1103/PhysRevD.54.1332.
```

```
@article{osti_286228,
```

title = {Cosmological-parameter determination with microwave background maps},

author = {Jungman, G. and Kamionkowski, M. and Kosowsky, A. and Spergel, D.N.},

abstractNote = {The angular power spectrum of the cosmic microwave background (CMB) contains information on virtually all cosmological parameters of interest, including the geometry of the Universe ({Omega}), the baryon density, the Hubble constant ({ital h}), the cosmological constant ({Lambda}), the number of light neutrinos, the ionization history, and the amplitudes and spectral indices of the primordial scalar and tensor perturbation spectra. We review the imprint of each parameter on the CMB. Assuming only that the primordial perturbations were adiabatic, we use a covariance-matrix approach to estimate the precision with which these parameters can be determined by a CMB temperature map as a function of the fraction of sky mapped, the level of pixel noise, and the angular resolution. For example, with no prior information about any of the cosmological parameters, a full-sky CMB map with 0.5{degree} angular resolution and a noise level of 15 {mu}K per pixel can determine {Omega}, {ital h}, and {Lambda} with standard errors of {plus_minus}0.1 or better, and provide determinations of other parameters which are inaccessible with traditional observations. Smaller beam sizes or prior information on some of the other parameters from other observations improves the sensitivity. The dependence on the underlying cosmological model is discussed. {copyright} {ital 1996 The American Physical Society.}},

doi = {10.1103/PhysRevD.54.1332},

journal = {Physical Review, D},

number = 2,

volume = 54,

place = {United States},

year = {1996},

month = {7}

}