Search

We describe a sampling method to estimate the polarized CMB signal from observed maps of the sky. We use a Metropolis-within-Gibbs algorithm to estimate the polarized CMB map, containing Q and U Stokes parameters at each pixel, and its covariance matrix. These can be used as inputs for cosmological analyses. The polarized sky signal is parameterized as the sum of three components: CMB, synchrotron emission, and thermal dust emission. The polarized Galactic components are modeled with spatially varying power law spectral indices for the synchrotron, and a fixed power law for the dust, and their component maps are estimated as by-products. We apply the method to simulated low resolution maps with pixels of side 7.2 degrees, using diagonal and full noise realizations drawn from the WMAP noise matrices. The CMB maps are recovered with goodness of fit consistent with errors. Computing the likelihood of the E-mode power in the maps as a function of optical depth to reionization, tau, for fixed temperature anisotropy power, we recover tau=0.091+-0.019 for a simulation with input tau=0.1, and mean tau=0.098 averaged over 10 simulations. A `null' simulation with no polarized CMB signal has maximum likelihood consistent with tau=0. The method is applied to the five-year WMAP data, using the K, Ka, Q and V channels. We find tau=0.090+-0.019, compared to tau=0.086+-0.016 from the template-cleaned maps used in the primary WMAP analysis. The synchrotron spectral index, beta, averaged over high signal-to-noise pixels with standard deviation sigma(beta)<0.25, but excluding ~6% of the sky masked in the Galactic plane, is -3.03+-0.04. This estimate does not vary significantly with Galactic latitude, although includes an informative prior., Comment: 11 pages, 9 figures, matches version accepted by ApJ

The Balloon-borne Large Aperture Submillimeter Telescope (BLAST) is a sub-orbital experiment designed to study the process of star formation in local galaxies (including the Milky Way) and in galaxies at cosmological distances. Using a 2-m Cassegrain telescope, BLAST images the sky onto a focal plane, which consists of 270 bolometric detectors split between three arrays, observing simultaneously in 30% wide bands, centered at 250, 350, and 500 microns. The diffraction-limited optical system provides a resolution of 30" at 250 microns. The pointing system enables raster-like scans with a positional accuracy of ~30", reconstructed to better than 5" rms in post-flight analysis. BLAST had two successful flights, from the Arctic in 2005, and from Antarctica in 2006, which provided the first high-resolution and large-area (~0.8-200 deg^2) submillimeter surveys at these wavelengths. As a pathfinder for the SPIRE instrument on Herschel, BLAST shares with the ESA satellite similar focal plane technology and scientific motivation. A third flight in 2009 will see the instrument modified to be polarization-sensitive (BLAST-Pol). With its unprecedented mapping speed and resolution, BLAST-Pol will provide insights into Galactic star-forming nurseries, and give the necessary link between the larger, coarse resolution surveys and the narrow, resolved observations of star-forming structures from space and ground based instruments being commissioned in the next 5 years., Comment: SPIE Conference Proceedings

The Balloon-borne Large Aperture Submillimeter Telescope (BLAST) operated successfully during a 100-hour flight from northern Sweden in June 2005 (BLAST05). As part of the calibration and pointing procedures, several compact sources were mapped, including solar system, Galactic, and extragalactic targets, specifically Pallas, CRL 2688, LDN 1014, IRAS 20126+4104, IRAS 21078+5211, IRAS 21307+5049, IRAS 22134+5834, IRAS 23011+6126, K3-50, W 75N, and Mrk 231. One additional source, Arp 220, was observed and used as our primary calibrator. Details of the overall BLAST05 calibration procedure are discussed here. The BLAST observations of each compact source are described, flux densities and spectral energy distributions are reported, and these are compared with previous measurements at other wavelengths. The 250, 350, and 500 um BLAST data can provide useful constraints to the amplitude and slope of the submillimeter continuum, which in turn may be useful for the improved calibration of other submillimeter instruments., Comment: 21 pages, 18 figures, accepted for publication in the Astrophysical Journal. BLAST maps are available at http://blastexperiment.info/results.shtml

We present new full-sky temperature and polarization maps in five frequency bands from 23 to 94 GHz, based on data from the first five years of the WMAP sky survey. The five-year maps incorporate several improvements in data processing made possible by the additional years of data and by a more complete analysis of the instrument calibration and in-flight beam response. We present several new tests for systematic errors in the polarization data and conclude that Ka band data (33 GHz) is suitable for use in cosmological analysis, after foreground cleaning. This significantly reduces the overall polarization uncertainty. With the 5 year WMAP data, we detect no convincing deviations from the minimal 6-parameter LCDM model: a flat universe dominated by a cosmological constant, with adiabatic and nearly scale-invariant Gaussian fluctuations. Using WMAP data combined with measurements of Type Ia supernovae and Baryon Acoustic Oscillations, we find (68% CL uncertainties): Omega_bh^2 = 0.02267 \pm 0.00059, Omega_ch^2 = 0.1131 \pm 0.0034, Omega_Lambda = 0.726 \pm 0.015, n_s = 0.960 \pm 0.013, tau = 0.084 \pm 0.016, and Delta_R^2 = (2.445 \pm 0.096) x 10^-9. From these we derive: sigma_8 = 0.812 \pm 0.026, H_0 = 70.5 \pm 1.3 km/s/Mpc, z_{reion} = 10.9 \pm 1.4, and t_0 = 13.72 \pm 0.12 Gyr. The new limit on the tensor-to-scalar ratio is r < 0.22 (95% CL). We obtain tight, simultaneous limits on the (constant) dark energy equation of state and spatial curvature: -0.14 < 1+w < 0.12 and -0.0179 < Omega_k < 0.0081 (both 95% CL). The number of relativistic degrees of freedom (e.g. neutrinos) is found to be N_{eff} = 4.4 \pm 1.5, consistent with the standard value of 3.04. Models with N_{eff} = 0 are disfavored at >99.5% confidence., Comment: 46 pages, 13 figures, and 7 tables. Version accepted for publication, ApJS, Feb-2009. Includes 5-year dipole results and additional references. Also available at http://lambda.gsfc.nasa.gov/product/map/dr3/map_bibliography.cfm

We present the temperature and polarization angular power spectra of the cosmic microwave background (CMB) derived from the first 5 years of WMAP data. The 5-year temperature (TT) spectrum is cosmic variance limited up to multipole l=530, and individual l-modes have S/N>1 for l<920. The best fitting six-parameter LambdaCDM model has a reduced chi^2 for l=33-1000 of chi^2/nu=1.06, with a probability to exceed of 9.3%. There is now significantly improved data near the third peak which leads to improved cosmological constraints. The temperature-polarization correlation (TE) is seen with high significance. After accounting for foreground emission, the low-l reionization feature in the EE power spectrum is preferred by \Delta\chi^2=19.6 for optical depth tau=0.089 by the EE data alone, and is now largely cosmic variance limited for l=2-6. There is no evidence for cosmic signal in the BB, TB, or EB spectra after accounting for foreground emission. We find that, when averaged over l=2-6, l(l+1)C^{BB}_l/2\pi < 0.15 uK^2 (95% CL)., Comment: 29 pages, 13 figures, accepted by ApJS

This paper focuses on cosmological constraints derived from analysis of WMAP data alone. A simple LCDM cosmological model fits the five-year WMAP temperature and polarization data. The basic parameters of the model are consistent with the three-year data and now better constrained: Omega_b h^2 = 0.02273+-0.00062, Omega_c h^2 = 0.1099+-0.0062, Omega_L = 0.742+-0.030, n_s = 0.963+0.014- 0.015, tau = 0.087+-0.017, sigma_8 = 0.796+-0.036. With five years of polarization data, we have measured the optical depth to reionization, tau>0, at 5 sigma significance. The redshift of an instantaneous reionization is constrained to be z_reion = 11.0+-1.4 with 68% confidence. This excludes a sudden reionization of the universe at z=6 at more than 3.5 sigma significance, suggesting that reionization was an extended process. Using two methods for polarized foreground cleaning we get consistent estimates for the optical depth, indicating an error due to foreground treatment of tau~0.01. This cosmological model also fits small-scale CMB data, and a range of astronomical data measuring the expansion rate and clustering of matter in the universe. We find evidence for the first time in the CMB power spectrum for a non-zero cosmic neutrino background, or a background of relativistic species, with the standard three light neutrino species preferred over the best-fit LCDM model with N_eff=0 at >99.5% confidence, and N_eff > 2.3 (95% CL) when varied. The five-year WMAP data improve the upper limit on the tensor-to-scalar ratio to r < 0.43 (95% CL), for power-law models. With longer integration we find no evidence for a running spectral index, with dn_s/dlnk = -0.037+-0.028., Comment: 49 pages, 18 figures, version accepted by ApJS. Original Section 2 moved to separate paper. For higher quality figs, see version on http://lambda.gsfc.nasa.gov

Cosmology and other scientific results from the WMAP mission require an accurate knowledge of the beam patterns in flight. While the degree of beam knowledge for the WMAP one-year and three-year results was unprecedented for a CMB experiment, we have significantly improved the beam determination as part of the five-year data release. Physical optics fits are done on both the A and the B sides for the first time. The cutoff scale of the fitted distortions on the primary mirror is reduced by a factor of ~2 from previous analyses. These changes enable an improvement in the hybridization of Jupiter data with beam models, which is optimized with respect to error in the main beam solid angle. An increase in main-beam solid angle of ~1% is found for the V2 and W1-W4 differencing assemblies. Although the five-year results are statistically consistent with previous ones, the errors in the five-year beam transfer functions are reduced by a factor of ~2 as compared to the three-year analysis. We present radiometry of the planet Jupiter as a test of the beam consistency and as a calibration standard; for an individual differencing assembly, errors in the measured disk temperature are ~0.5%., Comment: 48 pages, 16 figures; version with better quality figures available from http://lambda.gsfc.nasa.gov; revised version, accepted for Astrophysical Journal Supplement Series

We present the list of point sources found in the WMAP 5-year maps. The technique used in the first-year and three-year analysis now finds 390 point sources, and the five-year source catalog is complete for regions of the sky away from the galactic plane to a 2 Jy limit, with SNR > 4.7 in all bands in the least covered parts of the sky. The noise at high frequencies is still mainly radiometer noise, but at low frequencies the CMB anisotropy is the largest uncertainty. A separate search of CMB-free V-W maps finds 99 sources of which all but one can be identified with known radio sources. The sources seen by WMAP are not strongly polarized. Many of the WMAP sources show significant variability from year to year, with more than a 2:1 range between the minimum and maximum fluxes., Comment: 31 pages Latex with 4 embedded figures. Version accepted by the ApJ Supplements

(Abridged) The WMAP 5-year data strongly limit deviations from the minimal LCDM model. We constrain the physics of inflation via Gaussianity, adiabaticity, the power spectrum shape, gravitational waves, and spatial curvature. We also constrain the properties of dark energy, parity-violation, and neutrinos. We detect no convincing deviations from the minimal model. The parameters of the LCDM model, derived from WMAP combined with the distance measurements from the Type Ia supernovae (SN) and the Baryon Acoustic Oscillations (BAO), are: Omega_b=0.0456+-0.0015, Omega_c=0.228+-0.013, Omega_Lambda=0.726+-0.015, H_0=70.5+-1.3 km/s/Mpc, n_s=0.960+-0.013, tau=0.084+-0.016, and sigma_8=0.812+-0.026. With WMAP+BAO+SN, we find the tensor-to-scalar ratio r<0.22 (95% CL), and n_s>1 is disfavored regardless of r. We obtain tight, simultaneous limits on the (constant) equation of state of dark energy and curvature. We provide a set of "WMAP distance priors," to test a variety of dark energy models. We test a time-dependent w with a present value constrained as -0.33<1+w_0<0.21 (95% CL). Temperature and matter fluctuations obey the adiabatic relation to within 8.9% and 2.1% for the axion and curvaton-type dark matter, respectively. The TE and EB spectra constrain cosmic parity-violation. We find the limit on the total mass of neutrinos, sum(m_nu)<0.67 eV (95% CL), which is free from the uncertainty in the normalization of the large-scale structure data. The effective number of neutrino species is constrained as N_{eff} = 4.4+-1.5 (68%), consistent with the standard value of 3.04. Finally, limits on primordial non-Gaussianity are -9

We describe a map-making method which we have developed for the Balloon-borne Large Aperture Submillimeter Telescope (BLAST) experiment, but which should have general application to data from other submillimeter arrays. Our method uses a Maximum Likelihood based approach, with several approximations, which allows images to be constructed using large amounts of data with fairly modest computer memory and processing requirements. This new approach, Signal And Noise Estimation Procedure Including Correlations (SANEPIC), builds upon several previous methods, but focuses specifically on the regime where there is a large number of detectors sampling the same map of the sky, and explicitly allowing for the the possibility of strong correlations between the detector timestreams. We provide real and simulated examples of how well this method performs compared with more simplistic map-makers based on filtering. We discuss two separate implementations of SANEPIC: a brute-force approach, in which the inverse pixel-pixel covariance matrix is computed; and an iterative approach, which is much more efficient for large maps. SANEPIC has been successfully used to produce maps using data from the 2005 BLAST flight., Comment: 27 Pages, 15 figures; Submitted to the Astrophysical Journal; related results available at http://blastexperiment.info/ [the BLAST Webpage]

We present the first results from a new 250, 350, and 500 micron Galactic Plane survey taken with the Balloon-borne Large-Aperture Submillimeter Telescope (BLAST) in 2005. This survey's primary goal is to identify and characterize high-mass proto-stellar objects (HMPOs). The region studied here covers 4 sq. deg near the open cluster NGC 6823 in the constellation Vulpecula (l=59). We find 60 compact sources (<60'' diameter) detected simultaneously in all three bands. Their spectral energy distributions (SEDs) are constrained through BLAST, IRAS, Spitzer MIPS, and MSX photometry, with inferred dust temperatures spanning ~12-40K assuming a dust emissivity index beta=1.5. The luminosity-to-mass ratio, a distance-independent quantity, spans ~0.2-130 L_\odot M_\odot^{-1}. Distances are estimated from coincident 13CO (1->0) velocities combined with a variety of other velocity and morphological data in the literature. In total, 49 sources are associated with a molecular cloud complex encompassing NGC 6823 (distance ~2.3kpc), 10 objects with the Perseus Arm (~8.5kpc) and one object is probably in the outer Galaxy (~14kpc). Near NGC 6823, the inferred luminosities and masses of BLAST sources span ~40-10^4 L_\odot, and ~15-700 M_\odot, respectively. The mass spectrum is compatible with molecular gas masses in other high-mass star forming regions. Several luminous sources appear to be Ultra Compact HII regions powered by early B stars. However, many of the objects are cool, massive gravitationally-bound clumps with no obvious internal radiation from a protostar, and hence excellent HMPO candidates., Comment: 42 Pages, 20 figures; Accepted for publication in the Astrophysical Journal; maps and related results available at http://blastexperiment.info/

The Balloon-borne Large Aperture Submillimeter Telescope (BLAST) is a sub-orbital surveying experiment designed to study the evolutionary history and processes of star formation in local galaxies (including the Milky Way) and galaxies at cosmological distances. The BLAST continuum camera, which consists of 270 detectors distributed between 3 arrays, observes simultaneously in broad-band (30%) spectral-windows at 250, 350, and 500 microns. The optical design is based on a 2m diameter telescope, providing a diffraction-limited resolution of 30" at 250 microns. The gondola pointing system enables raster mapping of arbitrary geometry, with a repeatable positional accuracy of ~30"; post-flight pointing reconstruction to ~5" rms is achieved. The on-board telescope control software permits autonomous execution of a pre-selected set of maps, with the option of manual override. In this paper we describe the primary characteristics and measured in-flight performance of BLAST. BLAST performed a test-flight in 2003 and has since made two scientifically productive long-duration balloon flights: a 100-hour flight from ESRANGE (Kiruna), Sweden to Victoria Island, northern Canada in June 2005; and a 250-hour, circumpolar-flight from McMurdo Station, Antarctica, in December 2006., Comment: 38 Pages, 11 figures; Replaced with version accepted for publication in the Astrophysical Journal; related results available at http://blastexperiment.info/

We present a full-sky model of polarized Galactic microwave emission based on three years of observations by the Wilkinson Microwave Anisotropy Probe (WMAP) at frequencies from 23 to 94 GHz. The model compares maps of the Stokes Q and U components from each of the 5 WMAP frequency bands in order to separate synchrotron from dust emission, taking into account the spatial and frequency dependence of the synchrotron and dust components. This simple two-component model of the interstellar medium accounts for at least 97% of the polarized emission in the WMAP maps of the microwave sky. Synchrotron emission dominates the polarized foregrounds at frequencies below 50 GHz, and is comparable to the dust contribution at 65 GHz. The spectral index of the synchrotron component, derived solely from polarization data, is -3.2 averaged over the full sky, with a modestly flatter index on the Galactic plane. The synchrotron emission has mean polarization fraction 2--4% in the Galactic plane and rising to over 20% at high latitude, with prominent features such as the North Galactic Spur more polarized than the diffuse component. Thermal dust emission has polarization fraction 1% near the Galactic center, rising to 6% at the anti-center. Diffuse emission from high-latitude dust is also polarized with mean fractional polarization 0.036 +/- 0.011., Comment: 9 pages with 8 figures. For higher quality figures, see the version posted at http://lambda.gsfc.nasa.gov/product/map/dr2/map_bibliography.cfm

A simple cosmological model with only six parameters (matter density, Omega_m h^2, baryon density, Omega_b h^2, Hubble Constant, H_0, amplitude of fluctuations, sigma_8, optical depth, tau, and a slope for the scalar perturbation spectrum, n_s) fits not only the three year WMAP temperature and polarization data, but also small scale CMB data, light element abundances, large-scale structure observations, and the supernova luminosity/distance relationship. Using WMAP data only, the best fit values for cosmological parameters for the power-law flat LCDM model are (Omega_m h^2, Omega_b h^2, h, n_s, tau, sigma_8) = 0.1277+0.0080-0.0079, 0.02229+-0.00073, 0.732+0.031-0.032, 0.958+-0.016, 0.089+-0.030, 0.761+0.049-0.048). The three year data dramatically shrink the allowed volume in this six dimensional parameter space. Assuming that the primordial fluctuations are adiabatic with a power law spectrum, the WMAP data_alone_ require dark matter, and favor a spectral index that is significantly less than the Harrison-Zel'dovich-Peebles scale-invariant spectrum (n_s=1, r=0). Models that suppress large-scale power through a running spectral index or a large-scale cut-off in the power spectrum are a better fit to the WMAP and small scale CMB data than the power-law LCDM model; however, the improvement in the fit to the WMAP data is only Delta chi^2 = 3 for 1 extra degree of freedom. The combination of WMAP and other astronomical data yields significant constraints on the geometry of the universe, the equation of state of the dark energy, the gravitational wave energy density, and neutrino properties. Consistent with the predictions of simple inflationary theories, we detect no significant deviations from Gaussianity in the CMB maps., Comment: 91 pgs, 28 figs. Accepted version of the 3-year paper as posted to http://lambda.gsfc.nasa.gov/product/map/dr2/map_bibliography.cfm in January 2007

The WMAP satellite has completed 3 years of observations of the cosmic microwave background radiation. The 3-year data products include several sets of full sky maps of the Stokes I, Q and U parameters in 5 frequency bands, spanning 23 to 94 GHz, and supporting items, such as beam window functions and noise covariance matrices. The processing used to produce the current sky maps and supporting products represents a significant advancement over the first year analysis, and is described herein. Improvements to the pointing reconstruction, radiometer gain modeling, window function determination and radiometer spectral noise parametrization are presented. A detailed description of the updated data processing that produces maximum likelihood sky map estimates is presented, along with the methods used to produce reduced resolution maps and corresponding noise covariance matrices. Finally two methods used to evaluate the noise of the full resolution sky maps are presented along with several representative year-to-year null tests, demonstrating that sky maps produced from data from different observational epochs are consistent., Comment: 58 pgs, 16 figs. Accepted version of the 3-year paper as posted on http://lambda.gsfc.nasa.gov/product/map/dr2/map_bibliography.cfm in January 2007

We present new full-sky temperature maps in five frequency bands from 23 to 94 GHz, based on the first three years of the WMAP sky survey. The new maps, which are consistent with the first-year maps and more sensitive, incorporate improvements in data processing made possible by the additional years of data and by a more complete analysis of the polarization signal. These include refinements in the gain calibration and beam response models. We employ two forms of multi-frequency analysis to separate astrophysical foreground signals from the CMB, each of which improves on our first-year analyses. First, we form an improved 'Internal Linear Combination' map, based solely on WMAP data, by adding a bias correction step and by quantifying residual uncertainties in the resulting map. Second, we fit and subtract new spatial templates that trace Galactic emission; in particular, we now use low-frequency WMAP data to trace synchrotron emission. The WMAP point source catalog is updated to include 115 new sources. We derive the angular power spectrum of the temperature anisotropy using a hybrid approach that combines a maximum likelihood estimate at low l (large angular scales) with a quadratic cross-power estimate for l>30. Our best estimate of the CMB power spectrum is derived by averaging cross-power spectra from 153 statistically independent channel pairs. The combined spectrum is cosmic variance limited to l=400, and the signal-to-noise ratio per l-mode exceeds unity up to l=850. The first two acoustic peaks are seen at l=220.8 +- 0.7 and l=530.9 +- 3.8, respectively, while the first two troughs are seen at l=412.4 +- 1.9 and l=675.1 +- 11.1, respectively. The rise to the third peak is unambiguous; when the WMAP data are combined with higher resolution CMB measurements, the existence of a third acoustic peak is well established., Comment: 116 pgs, 24 figs. Accepted version of the 3-year paper as posted to http://lambda.gsfc.nasa.gov/product/map/dr2/map_bibliography.cfm in January 2007

The Wilkinson Microwave Anisotropy Probe WMAP has mapped the entire sky in five frequency bands between 23 and 94 GHz with polarization sensitive radiometers. We present three-year full-sky maps of the polarization and analyze them for foreground emission and cosmological implications. These observations open up a new window for understanding the universe. WMAP observes significant levels of polarized foreground emission due to both Galactic synchrotron radiation and thermal dust emission. The least contaminated channel is at 61 GHz. Informed by a model of the Galactic foreground emission, we subtract the foreground emission from the maps. In the foreground corrected maps, for l=2-6, we detect l(l+1) C_l^{EE} / (2 pi) = 0.086 +-0.029 microkelvin^2. This is interpreted as the result of rescattering of the CMB by free electrons released during reionization and corresponds to an optical depth of tau = 0.10 +- 0.03. We see no evidence for B-modes, limiting them to l(l+1) C_l^{BB} / (2 pi) = -0.04 +- 0.03 microkelvin^2. We find that the limit from the polarization signals alone is r<2.2 (95% CL) corresponding to a limit on the cosmic density of gravitational waves of Omega_{GW}h^2 < 5 times 10^{-12}. From the full WMAP analysis, we find r<0.55 (95% CL) corresponding to a limit of Omega_{GW}h^2 < 10^{-12} (95% CL)., Comment: 105 pgs, 28 figs. Accepted version of the 3-year paper as posted to http://lambda.gsfc.nasa.gov/product/map/dr2/map_bibliography.cfm in January 2007

EBEX is a balloon-borne polarimeter designed to measure the intensity and polarization of the cosmic microwave background radiation. The measurements would probe the inflationary epoch that took place shortly after the big bang and would significantly improve constraints on the values of several cosmological parameters. EBEX is unique in its broad frequency coverage and in its ability to provide critical information about the level of polarized Galactic foregrounds which will be necessary for all future CMB polarization experiments. EBEX consists of a 1.5 m Dragone-type telescope that provides a resolution of less than 8 arcminutes over four focal planes each of 4 degree diffraction limited field of view at frequencies up to 450 GHz. The experiment is designed to accommodate 330 transition edge bolometric detectors per focal plane, for a total of up to 1320 detectors. EBEX will operate with frequency bands centered at 150, 250, 350, and 450 GHz. Polarimetry is achieved with a rotating achromatic half-wave plate. EBEX is currently in the design and construction phase, and first light is scheduled for 2008., Comment: 13 pages, 10 figures. Figure 1 is changed from the one which appeared in the Proceedings of the SPIE

The first-year WMAP data, in combination with any one of a number of other cosmic probes, show that we live in a flat \Lambda-dominated CDM universe with \Omega_m ~ 0.27 and \Omega_\Lambda ~ 0.73. In this model the late-time action of the dark energy, through the integrated Sachs-Wolfe effect, should produce CMB anisotropies correlated with matter density fluctuations at z<2 (Crittenden & Turok 1996). The measurement of such a signal is an important independent check of the model. We cross-correlate the NRAO VLA Sky Survey radio source catalog (Condon et al. 1998) with the WMAP data in search of this signal, and see indications of the expected correlation. Assuming a flat \Lambda-CDM cosmology, we find \Omega_\Lambda>0 (95% CL, statistical errors only) with the peak of the likelihood at \Omega_\Lambda=0.68, consistent with the preferred WMAP value. A closed model with \Omega_m=1.28, h=0.33, and no dark energy component (\Omega_\Lambda=0), marginally consistent with the WMAP CMB TT angular power spectrum, would produce an anti-correlation between the matter distribution and the CMB. Our analysis of the cross-correlation of the WMAP data with the NVSS catalog rejects this cosmology at the 3\sigma level., Comment: 13 pages, 4 figures, submitted to ApJ

The Wilkinson Microwave Anisotropy Probe (WMAP) has mapped the full sky in Stokes I, Q, and U parameters at frequencies 23, 33, 41, 61, and 94 GHz. We detect correlations between the temperature and polarization maps significant at more than 10 standard deviations. The correlations are present in all WMAP frequency bands with similar amplitude from 23 to 94 GHz, and are consistent with a superposition of a CMB signal with a weak foreground. The fitted CMB component is robust against different data combinations and fitting techniques. On small angular scales theta < 5 deg, the WMAP data show the temperature-polarization correlation expected from adiabatic perturbations in the temperature power spectrum. The data for l > 20 agree well with the signal predicted solely from the temperature power spectra, with no additional free parameters. We detect excess power on large angular scales (theta > 10 deg) compared to predictions based on the temperature power spectra alone. The excess power is well described by reionization at redshift 11 < z_r < 30 at 95% confidence, depending on the ionization history. A model-independent fit to reionization optical depth yields results consistent with the best-fit LambdaCDM model, with best fit value tau = 0.17 +- 0.04 at 68% confidence, including systematic and foreground uncertainties. This value is larger than expected given the detection of a Gunn-Peterson trough in the absorption spectra of distant quasars, and implies that the universe has a complex ionization history: WMAP has detected the signal from an early epoch of reionization., Comment: Replaced with version accepted by ApJ; Fig. 9 caption fixed. One of 13 companion papers on first-year WMAP results; 33 pages, 9 figures; version with higher quality figures is at http://lambda.gsfc.nasa.gov/

We confront predictions of inflationary scenarios with the WMAP data, in combination with complementary small-scale CMB measurements and large-scale structure data. The WMAP detection of a large-angle anti-correlation in the temperature--polarization cross-power spectrum is the signature of adiabatic superhorizon fluctuations at the time of decoupling. The WMAP data are described by pure adiabatic fluctuations: we place an upper limit on a correlated CDM isocurvature component. Using WMAP constraints on the shape of the scalar power spectrum and the amplitude of gravity waves, we explore the parameter space of inflationary models that is consistent with the data. We place limits on inflationary models; for example, a minimally-coupled lambda phi^4 is disfavored at more than 3-sigma using WMAP data in combination with smaller scale CMB and large scale structure survey data. The limits on the primordial parameters using WMAP data alone are: n_s(k_0=0.002 Mpc^{-1})=1.20_{-0.11}^{+0.12}, dn/dlnk=-0.077^{+0.050}_{- 0.052}, A(k_0=0.002 Mpc}^{-1})=0.71^{+0.10}_{-0.11} (68% CL), and r(k_0=0.002 Mpc^{-1})<1.28 (95% CL)., Comment: Accepted by ApJ; 49 pages, 9 figures. V2: Gives constraints from WMAP data alone. Corrected approximation which made the constraints in Table 1 to shift slightly. Corrected the Inflation Flow following the revision to Kinney, astro-ph/0206032. No conclusions have been changed. For a detailed list of changes see http://www.astro.princeton.edu/~hiranya/README.ERRATA.txt

We present limits to the amplitude of non-Gaussian primordial fluctuations in the WMAP 1-year cosmic microwave background sky maps. A non-linear coupling parameter, f_NL, characterizes the amplitude of a quadratic term in the primordial potential. We use two statistics: one is a cubic statistic which measures phase correlations of temperature fluctuations after combining all configurations of the angular bispectrum. The other uses the Minkowski functionals to measure the morphology of the sky maps. Both methods find the WMAP data consistent with Gaussian primordial fluctuations and establish limits, -58

The WMAP satellite has completed one year of measurements of the Cosmic Microwave Background (CMB) radiation using 20 differential high-electron-mobility-transistor (HEMT) based radiometers. All the radiometers are functioning nominally, and characterizations of the on-orbit radiometer performance are presented, with an emphasis on properties that are required for the production of sky maps from the time ordered data. A radiometer gain model, used to smooth and interpolate the CMB dipole gain measurements is also presented. No degradation in the sensitivity of any of the radiometers has been observed during the first year of observations., Comment: One of thirteen companion papers on first-year WMAP results submitted to ApJ; 22 pages, 8 figures; a version with higher quality figures is also available at http://lambda.gsfc.nasa.gov/product/map/map_bibliography.html

The CMB has distinct peaks in both its temperature angular power spectrum (TT) and temperature-polarization cross-power spectrum (TE). From the WMAP data we find the first peak in the temperature spectrum at l = 220.1 +- 0.8 with an amplitude of 74.7 +- 0.5 microK; the first trough at l = 411.7 +- 3.5 with an amplitude of 41.0 +- 0.5 microK; and the second peak at l = 546 +- 10 with an amplitude of 48.8 +- 0.9 microK. The TE spectrum has an antipeak at l = 137 +- 9 with a cross-power of -35 +- 9 microK^2, and a peak at l = 329 +- 19 with cross-power 105 +- 18 microK^2. All uncertainties are 1 sigma and include calibration and beam errors. An intuition for how the data determine the cosmological parameters may be gained by limiting one's attention to a subset of parameters and their effects on the peak characteristics. We interpret the peaks in the context of a flat adiabatic LambdaCDM model with the goal of showing how the cosmic baryon density, Omega_b h^2, matter density, Omega_m h^2, scalar index, n_s, and age of the universe are encoded in their positions and amplitudes. To this end, we introduce a new scaling relation for the TE antipeak-to-peak amplitude ratio and recompute known related scaling relations for the TT spectrum in light of the WMAP data. From the scaling relations, we show that WMAP's tight bound on Omega_b h^2 is intimately linked to its robust detection of the first and second peaks of the TT spectrum., Comment: Replaced with version accepted by ApJ. One of 13 companion papers on first-year WMAP results; 21 pages with 3 figures; a version with higher quality figures is at http://lambda.gsfc.nasa.gov/

Since the Galactic center is ~1000 times brighter than fluctuations in the Cosmic Microwave Background (CMB), CMB experiments must carefully account for stray Galactic pickup. We present the level of contamination due to sidelobes for the year one CMB maps produced by the WMAP observatory. For each radiometer, full 4 pi sr antenna gain patterns are determined from a combination of numerical prediction, ground-based and space-based measurements. These patterns are convolved with the WMAP year one sky maps and observatory scan pattern to generate expected sidelobe signal contamination, for both intensity and polarized microwave sky maps. Outside of the Galactic plane, we find rms values for the expected sidelobe pickup of 15, 2.1, 2.0, 0.3, 0.5 uK for K, Ka, Q, V, and W bands respectively. Except at K band, the rms polarized contamination is <<1 uK. Angular power spectra of the Galactic pickup are presented., Comment: One of thirteen companion papers on first-year WMAP results submitted to ApJ; 23 pages, 7 figures; a version with higher quality figures is also available at http://lambda.gsfc.nasa.gov/product/map/map_bibliography.html

Knowledge of the beam profiles is of critical importance for interpreting data from cosmic microwave background experiments. In this paper, we present the characterization of the in-flight optical response of the WMAP satellite. The main beam intensities have been mapped to < -30 dB of their peak values by observing Jupiter with the satellite in the same observing mode as for CMB observations. The beam patterns closely follow the pre-launch expectations. The full width at half maximum is a function of frequency and ranges from 0.82 degrees at 23 GHz to 0.21 degrees at 94 GHz; however, the beams are not Gaussian. We present: (a) the beam patterns for all ten differential radiometers and show that the patterns are substantially independent of polarization in all but the 23 GHz channel; (b) the effective symmetrized beam patterns that result from WMAP's compound spin observing pattern; (c) the effective window functions for all radiometers and the formalism for propagating the window function uncertainty; and (d) the conversion factor from point source flux to antenna temperature. A summary of the systematic uncertainties, which currently dominate our knowledge of the beams, is also presented. The constancy of Jupiter's temperature within a frequency band is an essential check of the optical system. The tests enable us to report a calibration of Jupiter to 1-3% accuracy relative to the CMB dipole., Comment: Replaced with version accepted by ApJ. One of thirteen companion papers on first-year WMAP results; 27 pages, 6 figures; a version with higher quality figures is at http://lambda.gsfc.nasa.gov/

We present full sky microwave maps in five bands (23 to 94 GHz) from the WMAP first year sky survey. Calibration errors are <0.5% and the low systematic error level is well specified. The 21 per mode to l=658. The temperature-polarization cross-power spectrum reveals both acoustic features and a large angle correlation from reionization. The optical depth of reionization is 0.17 +/- 0.04, which implies a reionization epoch of 180+220-80 Myr (95% CL) after the Big Bang at a redshift of 20+10-9 (95% CL) for a range of ionization scenarios. This early reionization is incompatible with the presence of a significant warm dark matter density. The age of the best-fit universe is 13.7 +/- 0.2 Gyr old. Decoupling was 379+8-7 kyr after the Big Bang at a redshift of 1089 +/- 1. The thickness of the decoupling surface was dz=195 +/- 2. The matter density is Omega_m h^2 = 0.135 +0.008 -0.009, the baryon density is Omega_b h^2 = 0.0224 +/- 0.0009, and the total mass-energy of the universe is Omega_tot = 1.02 +/- 0.02. The spectral index of scalar fluctuations is fit as n_s = 0.93 +/- 0.03 at wavenumber k_0 = 0.05 Mpc^-1, with a running index slope of dn_s/d ln k = -0.031 +0.016 -0.018 in the best-fit model. This flat universe model is composed of 4.4% baryons, 22% dark matter and 73% dark energy. The dark energy equation of state is limited to w<-0.78 (95% CL). Inflation theory is supported with n_s~1, Omega_tot~1, Gaussian random phases of the CMB anisotropy, and superhorizon fluctuations. An admixture of isocurvature modes does not improve the fit. The tensor-to-scalar ratio is r(k_0=0.002 Mpc^-1)<0.90 (95% CL)., Comment: Replaced with version accepted by ApJ. One of thirteen companion papers on first-year WMAP results; 43 pages, 17 figures; a version with higher quality graphics is at http://lambda.gsfc.nasa.gov/

We describe the calibration and data processing methods used to generate full-sky maps of the cosmic microwave background (CMB) from the first year of Wilkinson Microwave Anisotropy Probe (WMAP) observations. Detailed limits on residual systematic errors are assigned based largely on analyses of the flight data supplemented, where necessary, with results from ground tests. The data are calibrated in flight using the dipole modulation of the CMB due to the observatory's motion around the Sun. This constitutes a full-beam calibration source. An iterative algorithm simultaneously fits the time-ordered data to obtain calibration parameters and pixelized sky map temperatures. The noise properties are determined by analyzing the time-ordered data with this sky signal estimate subtracted. Based on this, we apply a pre-whitening filter to the time-ordered data to remove a low level of 1/f noise. We infer and correct for a small ~1% transmission imbalance between the two sky inputs to each differential radiometer, and we subtract a small sidelobe correction from the 23 GHz (K band) map prior to further analysis. No other systematic error corrections are applied to the data. Calibration and baseline artifacts, including the response to environmental perturbations, are negligible. Systematic uncertainties are comparable to statistical uncertainties in the characterization of the beam response. Both are accounted for in the covariance matrix of the window function and are propagated to uncertainties in the final power spectrum. We characterize the combined upper limits to residual systematic uncertainties through the pixel covariance matrix., Comment: One of 13 companion papers on first-year WMAP results submitted to ApJ; 58 pages with 14 figures; a version with higher quality figures is at http://lambda.gsfc.nasa.gov/product/map/map_bibliography.html

Full sky maps are made in five microwave frequency bands to separate the temperature anisotropy of the CMB from foreground emission. We define masks that excise regions of high foreground emission. The effectiveness of template fits to remove foreground emission from the WMAP data is examined. These efforts result in a CMB map with minimal contamination and a demonstration that the WMAP CMB power spectrum is insensitive to residual foreground emission. We construct a model of the Galactic emission components. We find that the Milky Way resembles other normal spiral galaxies between 408 MHz and 23 GHz, with a synchrotron spectral index that is flattest (beta ~ -2.5) near star-forming regions, especially in the plane, and steepest (beta ~ -3) in the halo. The significant synchrotron index steepening out of the plane suggests a diffusion process in which the halo electrons are trapped in the Galactic potential long enough to suffer synchrotron and inverse Compton energy losses and hence a spectral steepening. The synchrotron index is steeper in the WMAP bands than in lower frequency radio surveys, with a spectral break near 20 GHz to beta < -3. The modeled thermal dust spectral index is also steep in the WMAP bands, with beta ~ 2.2. Microwave and H alpha measurements of the ionized gas agree. Spinning dust emission is limited to < ~5% of the Ka-band foreground emission. A catalog of 208 point sources is presented. Derived source counts suggest a contribution to the anisotropy power from unresolved sources of (15.0 +- 1.4) 10^{-3} microK^2 sr at Q-band and negligible levels at V-band and W-band., Comment: Replaced with version accepted by ApJ. One of 13 companion papers on first-year WMAP results. 42 pages with 13 figures; a version with higher quality figures is at http://lambda.gsfc.nasa.gov/

We present the angular power spectrum derived from the first-year Wilkinson Microwave Anisotropy Probe (WMAP) sky maps. We study a variety of power spectrum estimation methods and data combinations and demonstrate that the results are robust. The data are modestly contaminated by diffuse Galactic foreground emission, but we show that a simple Galactic template model is sufficient to remove the signal. Point sources produce a modest contamination in the low frequency data. After masking ~700 known bright sources from the maps, we estimate residual sources contribute ~3500 uK^2 at 41 GHz, and ~130 uK^2 at 94 GHz, to the power spectrum l*(l+1)*C_l/(2*pi) at l=1000. Systematic errors are negligible compared to the (modest) level of foreground emission. Our best estimate of the power spectrum is derived from 28 cross-power spectra of statistically independent channels. The final spectrum is essentially independent of the noise properties of an individual radiometer. The resulting spectrum provides a definitive measurement of the CMB power spectrum, with uncertainties limited by cosmic variance, up to l~350. The spectrum clearly exhibits a first acoustic peak at l=220 and a second acoustic peak at l~540 and it provides strong support for adiabatic initial conditions. Kogut et al. (2003) analyze the C_l^TE power spectrum, and present evidence for a relatively high optical depth, and an early period of cosmic reionization. Among other things, this implies that the temperature power spectrum has been suppressed by \~30% on degree angular scales, due to secondary scattering., Comment: One of thirteen companion papers on first-year WMAP results submitted to ApJ; 44 pages, 14 figures; a version with higher quality figures is also available at http://lambda.gsfc.nasa.gov/product/map/map_bibliography.html

We describe our methodology for comparing the WMAP measurements of the cosmic microwave background (CMB) and other complementary data sets to theoretical models. The unprecedented quality of the WMAP data, and the tight constraints on cosmological parameters that are derived, require a rigorous analysis so that the approximations made in the modeling do not lead to significant biases. We describe our use of the likelihood function to characterize the statistical properties of the microwave background sky. We outline the use of the Monte Carlo Markov Chains to explore the likelihood of the data given a model to determine the best fit cosmological parameters and their uncertainties. We add to the WMAP data the l>~700 CBI and ACBAR measurements of the CMB, the galaxy power spectrum at z~0 obtained from the 2dF galaxy redshift survey (2dFGRS), and the matter power spectrum at z~3 as measured with the Ly alpha forest. These last two data sets complement the CMB measurements by probing the matter power spectrum of the nearby universe. Combining CMB and 2dFGRS requires that we include in our analysis a model for galaxy bias, redshift distortions, and the non-linear growth of structure. We show how the statistical and systematic uncertainties in the model and the data are propagated through the full analysis., Comment: Replaced with version with final edits for ApJ. One of thirteen companion papers on first-year WMAP results; 38 pages, 8 figures; a version with higher quality figures is available at http://lambda.gsfc.nasa.gov/

WMAP precision data enables accurate testing of cosmological models. We find that the emerging standard model of cosmology, a flat Lambda-dominated universe seeded by nearly scale-invariant adiabatic Gaussian fluctuations, fits the WMAP data. With parameters fixed only by WMAP data, we can fit finer scale CMB measurements and measurements of large scle structure (galaxy surveys and the Lyman alpha forest). This simple model is also consistent with a host of other astronomical measurements. We then fit the model parameters to a combination of WMAP data with other finer scale CMB experiments (ACBAR and CBI), 2dFGRS measurements and Lyman alpha forest data to find the model's best fit cosmological parameters: h=0.71+0.04-0.03, Omega_b h^2=0.0224+-0.0009, Omega_m h^2=0.135+0.008-0.009, tau=0.17+-0.06, n_s(0.05/Mpc)=0.93+-0.03, and sigma_8=0.84+-0.04. WMAP's best determination of tau=0.17+-0.04 arises directly from the TE data and not from this model fit, but they are consistent. These parameters imply that the age of the universe is 13.7+-0.2 Gyr. The data favors but does not require a slowly varying spectral index. By combining WMAP data with other astronomical data sets, we constrain the geometry of the universe, Omega_tot = 1.02 +- 0.02, the equation of state of the dark energy w < -0.78 (95% confidence limit assuming w >= -1), and the energy density in stable neutrinos, Omega_nu h^2 < 0.0076 (95% confidence limit). For 3 degenerate neutrino species, this limit implies that their mass is less than 0.23 eV (95% confidence limit). The WMAP detection of early reionization rules out warm dark matter., Comment: Replaced with version accepted by ApJ. One of thirteen companion papers on first-year WMAP results; 51 pages, 17 figures; a version with higher quality figures is available at http://lambda.gsfc.nasa.gov/

The Microwave Anisotropy Probe (MAP) satellite, launched June 30, 2001, will produce full sky maps of the cosmic microwave background radiation in 5 frequency bands spanning 20 - 106 GHz. MAP contains 20 differential radiometers built with High Electron Mobility Transistor (HEMT) amplifiers with passively cooled input stages. The design and test techniques used to evaluate and minimize systematic errors and the pre-launch performance of the radiometers for all five bands are presented., Comment: Updated with comments; 24 pages with 10 low-resolution figures; version with better figures is at http://lambda.gsfc.nasa.gov/product/map/map_bibliography.html

The primary goal of the MAP satellite, now in orbit, is to make high fidelity polarization sensitive maps of the full sky in five frequency bands between 20 and 100 GHz. From these maps we will characterize the properties of the cosmic microwave background (CMB) anisotropy and Galactic and extragalactic emission on angular scales ranging from the effective beam size, <0.23 degree, to the full sky. MAP is a differential microwave radiometer. Two back-to-back shaped offset Gregorian telescopes feed two mirror symmetric arrays of ten corrugated feeds. We describe the prelaunch design and characterization of the optical system, compare the optical models to the measurements, and consider multiple possible sources of systematic error., Comment: ApJ in press; 22 pages with 11 low resolution figures; paper is available with higher quality figures at http://map.gsfc.nasa.gov/m_mm/tp_links.html

The purpose of the MAP mission is to determine the geometry, content, and evolution of the universe via a 13 arcmin full-width-half-max (FWHM) resolution full sky map of the temperature anisotropy of the cosmic microwave background radiation with uncorrelated pixel noise, minimal systematic errors, multifrequency observations, and accurate calibration. These attributes were key factors in the success of NASA's Cosmic Background Explorer (COBE) mission, which made a 7 degree FWHM resolution full sky map, discovered temperature anisotropy, and characterized the fluctuations with two parameters, a power spectral index and a primordial amplitude. Following COBE considerable progress has been made in higher resolution measurements of the temperature anisotropy. With 45 times the sensitivity and 33 times the angular resolution of the COBE mission, MAP will vastly extend our knowledge of cosmology. MAP will measure the physics of the photon-baryon fluid at recombination. From this, MAP measurements will constrain models of structure formation, the geometry of the universe, and inflation. In this paper we present a pre-launch overview of the design and characteristics of the MAP mission. This information will be necessary for a full understanding of the MAP data and results, and will also be of interest to scientists involved in the design of future cosmic microwave background experiments and/or space science missions., Comment: ApJ in press; 22 pages with 10 low-resolution figures; version with better quality figures is available at http://map.gsfc.nasa.gov/m_mm/tp_links.html

We present the design, manufacturing methods, and characterization of 20 microwave feed horns currently in use on the Microwave Anisotropy Probe (MAP) satellite. The nature of the cosmic microwave background (CMB) anisotropy requires a detailed understanding of the properties of every optical component of a microwave telescope. In particular, the properties of the feeds must be known so that the forward gain and sidelobe response of the telescope can be modeled and so that potential systematic effects may be computed. MAP requires low emissivity, azimuthally symmetric, low-sidelobe feeds in five microwave bands (K, Ka, Q, V, and W) that fit within a constrained geometry. The beam pattern of each feed is modeled and compared with measurements; the agreement is generally excellent to the -60 dB level (80 degrees from the beam peak). This agreement verifies the beam-predicting software and the manufacturing process. The feeds also affect the properties and modeling of the microwave receivers. To this end, we show that the reflection from the feeds is less than -25 dB over most of each band and that their emissivity is acceptable. The feeds meet their multiple requirements., Comment: 9 pages with 7 figures, of which 2 are in low-resolution versions; paper is available with higher quality figures at http://map.gsfc.nasa.gov/m_mm/tp_links.html

Future extragalactic sub-millimetre and millimetre surveys have the potential to provide a sensitive census of the level of obscured star formation in galaxies at all redshifts. While in general there is good agreement between the source counts from existing SCUBA (850um) and MAMBO (1.25mm) surveys of different depths and areas, it remains difficult to determine the redshift distribution and bolometric luminosities of the sub-millimetre and millimetre galaxy population. This is principally due to the ambiguity in identifying an individual sub-millimetre source with its optical, IR or radio counterpart which, in turn, prevents a confident measurement of the spectroscopic redshift. Additionally, the lack of data measuring the rest-frame FIR spectral peak of the sub-millimetre galaxies gives rise to poor constraints on their rest-frame FIR luminosities and star formation rates. In this paper we describe Monte-Carlo simulations of ground-based, balloon-borne and satellite sub-millimetre surveys that demonstrate how the rest-frame FIR-sub-millimetre spectral energy distributions (250-850um) can be used to derive photometric redshifts with an r.m.s accuracy of +/- 0.4 over the range 0 < z < 6. This opportunity to break the redshift deadlock will provide an estimate of the global star formation history for luminous optically-obscured galaxies [L(FIR) > 3 x 10^12 Lsun] with an accuracy of 20 per cent., Comment: 14 pages, 22 figures, submitted to MNRAS, replaced with accepted version

We use data from the White Dish experiment to set limits on cosmic microwave background radiation anisotropies in open and spatially-flat-Lambda cold dark matter cosmogonies. We account for the White Dish calibration uncertainty, and marginalize over the offset and gradient removed from the data. Our 2-sigma upper limits are larger than those derived previously. These upper limits are consistent with those derived from the $COBE$-DMR data for all models tested., Comment: 17 pages of latex. Uses aasms4.sty. 4 figures included. Submitted to ApJS

Results are reported from the first flight of a new balloon-borne instrument, BAM (Balloon-borne Anisotropy Measurement), designed to search for cosmic microwave background (CMB) anisotropy. The instrument uses a cryogenic differential Fourier transform spectrometer to obtain data in five spectral channels whose central frequencies lie in the range 3.7 cm^{-1} to 8.5 cm^{-1}. The spectrometer is coupled to an off-axis prime focus telescope; the combination yields difference spectra of two regions on the sky defined by 0\fdg 7 FWHM beams separated by 3\fdg 6. Single differences obtained at ten sky positions show statistically significant fluctuations. Assuming Gaussian correlated anisotropy, for the band average 3.1 cm^{-1} to 9.2 cm^{-1}, one finds $\Delta T/T = 3.1^{+3.1}_{1.1}\times 10^{-5}$ (90% confidence interval) for a correlation angle of 1\fdg 2. This corresponds to $Q_{flat} = 35.9^{17.7}_{6.3} \mu K$ (1\sigma)., Comment: 18 pages, 3 Postscript figures, uses aasms4.sty. Accepted for publication in Ap.J.Lett

A new instrument, BAM (Balloon-borne Anisotropy Measurement), designed to measure cosmic microwave background (CMB) anisotropy at medium angular scales was flown for the first time in July of 1995. BAM is unique in that it uses a cryogenic differential Fourier transform spectrometer coupled to a lightweight off-axis telescope. The very successful first flight of BAM demonstrates the potential of the instrument for obtaining high quality CMB anisotropy data., Comment: 6 pages, 3 EPS figures, TeX. To appear in Proceedings of the XXXIst Moriond Meeting "Microwave Background Anisotropies", Les Arcs (France), March 16-23 1996

We present cosmological parameter constraints based on the final nine-year Wilkinson Microwave Anisotropy Probe (WMAP) data, in conjunction with a number of additional cosmological data sets. The WMAP data alone, and in combination, continue to be remarkably well fit by a six-parameter Lambda-CDM model. When WMAP data are combined with measurements of the high-l cosmic microwave background anisotropy, the baryon acoustic oscillation scale, and the Hubble constant, the matter and energy densities Omega(sub b)h(exp 2), Omega(sub c)h(exp 2)and Omega(sub Lambda), are each determined to a precision of approx. 1.5%. The amplitude of the primordial spectrum is measured to within 3%, and there is now evidence for a tilt in the primordial spectrum at the 5 sigma level, confirming the first detection of tilt based on the five-year WMAP data. At the end of the WMAP mission, the nine-year data decrease the allowable volume of the six-dimensional Lambda-CDM parameter space by a factor of 68,000 relative to pre-WMAP measurements. We investigate a number of data combinations and show that their Lambda-CDM parameter fits are consistent. New limits on deviations from the six-parameter model are presented, for example: the fractional contribution of tensor modes is limited to r < 0.13 (95% CL); the spatial curvature parameter is limited to Omega(sub kappa) = (0.0027 (sub +0.0039) (sup −0.0038;) the summed mass of neutrinos is limited to Sigma M(sub nu) < 0.44 eV (95% CL); and the number of relativistic species is found to lie within N(sub eff) = 3.84 +/- 0+/-40, when the full data are analyzed. The joint constraint on N(sub eff) and the primordial helium abundance, Y(sub He), agrees with the prediction of standard big bang nucleosynthesis. We compare recent Planck measurements of the Sunyaev-Zel'dovich effect with our seven-year measurements, and show their mutual agreement. Our analysis of the polarization pattern around temperature extrema is updated. This confirms a fundamental prediction of the standard cosmological model and provides a striking illustration of acoustic oscillations and adiabatic initial conditions in the early universe.

We present the final nine-year maps and basic results from the Wilkinson Microwave Anisotropy Probe (WMAP) mission. The full nine-year analysis of the time-ordered data provides updated characterizations and calibrations of the experiment. We also provide new nine-year full sky temperature maps that were processed to reduce the asymmetry of the effective beams. Temperature and polarization sky maps are examined to separate cosmic microwave background (CMB) anisotropy from foreground emission, and both types of signals are analyzed in detail.We provide new point source catalogs as well as new diffuse and point source foreground masks. An updated template-removal process is used for cosmological analysis; new foreground fits are performed, and new foreground reduced are presented.We nowimplement an optimal C(exp -1)1 weighting to compute the temperature angular power spectrum. The WMAP mission has resulted in a highly constrained Lambda-CDM cosmological model with precise and accurate parameters in agreement with a host of other cosmological measurements. When WMAP data are combined with finer scale CMB, baryon acoustic oscillation, and Hubble constant measurements, we find that big bang nucleosynthesis is well supported and there is no compelling evidence for a non-standard number of neutrino species (N(sub eff) = 3.84 +/- 0.40). The model fit also implies that the age of the universe is (sub 0) = 13.772 +/- 0.059 Gyr, and the fit Hubble constant is H(sub 0) = 69.32 +/- 0.80 km/s/ Mpc. Inflation is also supported: the fluctuations are adiabatic, with Gaussian random phases; the detection of a deviation of the scalar spectral index from unity, reported earlier by the WMAP team, now has high statistical significance (n(sub s) = 0.9608+/-0.0080); and the universe is close to flat/Euclidean (Omega = −0.0027+0.0039/−0.0038). Overall, the WMAP mission has resulted in a reduction of the cosmological parameter volume by a factor of 68,000 for the standard six-parameter Lambda-CDM model, based on CMB data alone. For a model including tensors, the allowed seven-parameter volume has been reduced by a factor 117,000. Other cosmological observations are in accord with the CMB predictions, and the combined data reduces the cosmological parameter volume even further.With no significant anomalies and an adequate goodness of fit, the inflationary flat Lambda-CDM model and its precise and accurate parameters rooted in WMAP data stands as the standard model of cosmology.