1212.4834
The merger rates and sizes of galaxies across the peak epoch of star formation from the HiZELS survey
Stott, et al
HiZELS Narrow-band H-alpha survey, combined with CANDELS, UKIDSS and WIRDS NIR imaging, to invesitgate the morphologies, merger rates and sizes of a sample of H-alpha emitting galaxies in the 0.40<z<2.23, an epoch encompassing the rise to the peak of the SFR density. Merger rates are estimated from space- and ground-based imaging using the M20 coefficient [what's that?]. To account for the increase in the specific SFR (sSFR) of the SF 'main-sequence' with z, normalize the SFR of galaxies at each epoch to the typical value derived from the H-alpha LF. Once this trend in sSFR is removed, see no evidence for an increase in the number density of SF galaxies or merger rate with redshift. Conclude that neither is the main driver of the enhanced SFR density at z=1-2, with secular processes such as instabilities within efficiently fueled, gas-rich discs or multiple minor mergers the most likely alternatives. However, find that 40-50% of starburst galaxies, those with enhanced specific SF at their epoch, are major mergers and this fraction is z independent. Finally, find that the typical size of a SF galaxy of a given mass does not evolve across the redshift range considered, suggesting a universal size-mass relation. Taken in combination, these results indicate a SF galaxy population that is statistically similar in physical size, merger rate and mass over the 6 Gyr covered in this study, despite the increase in typical sSFR.
1212.4835
Probing high-redshift galaxy formation at the highest luminosities: new insights from DEIMOS spectroscopy
Lee, Dey, Cooper, Reddy, Jannuzi
Most UV-luinous SF galaxies at 3.2,z<4.6; sample contains L*<L<7L*, largest sample to date at these z. Clean selection of photometric candidates validated. Fraction of Lya emitters increases with decreasing UV luminosity. Find strong evidence of large-scale outflows, transporting the neutral/ionized gas in the ISM away from the galaxy. Galaxies exhibiting both interstellar absorption and Lya emission lines show a significant velocity offset between the 2 features (200-1140 km/s). Find tentative evidence that this measure of the outflow velocity increases with UV luminosity and/or stellar mass. The luminosity- and mass-dependent outflow strengths suggest that the efficiency of feedback and enrichment of the surrounding medium depend on these parameters. Present composite spectra of the absorption-line-only and Lya-emitting subsets of the UV luminous galaxies at z~3.7. The composite spectra are similar to those of lower-z and lower-luminosity LBG samples, but with some subtle differences. Analysis of the composite spectra suggest that the UV luminous LBGs at z~3.7 may have a higher covering fraction of absorbing gas, and may be older than their lower-z and lower-luminosity counterparts. In addition, 5 galaxies discover that belong to a massive over density at z=3.78. 2 galaxies each show 2 distinct sets of interstellar absorption features. The latter may be a sign of a final stage of major merger, or clumpy disk formation. Their presence implies that frequency of such sources among the luminous z~3.7 LBGs may be an order of magnitude higher than in lower redshift and lower luminosity samples.
1212.4844
The cosmic MeV neutrino background as a laboratory for black hole formation
Yuksel, Kistler
Calculations of the cosmic rate of corse collapses, and the associated neutrino flux, commonly assume that a fixed fraction of massive stars collapse to black holes. Argue that recent results suggest that this fraction instead increases with z. With relatively more stars vanishing as "unnovae" in the distant universe, the detectability of the cosmic MeV neutrino background is improved due to their hotter neutrino spectrum, and expectations for supernova surveys are reduced. We conclude that neutrino detectors, after the flux from normal SNe is isolated via either improved modeling or the next Galactic SN, can probe the conditions and history of BH formation.
1212.4848
The fundamental metallicity relation reduces type Ia SN Hubble residuals more than host mass alone
Hayden, Gupta, Garnavich, Mannucci, Nichol, Sako
* FMR: mass-metllicity-SFR relation.
SNIa Hubble residuals have been shown to correlate with host galaxy mass, imposing a major obstacle for their use in measuring DE properties. Here, calibrate the fundamental metallicity relation (FMR) of Mannucci+ (2010) for host mass and SFR measured from broad-band colors alone. Apply the FMR to the large number of hosts from the SSS-II sample of GUpta+ 2011 and find that the scatter in the Hubble residuals is significantly reduced when compared with using only stellar mass (or the mass-metallicity relation) as a fit parameter. Calibration of the FMR is restricted to only SF galaxies and in the Hubble residual calculation include only hosts with log(SFR)>-2. Results strongly suggest that metallicity is the underlying source of the correlation between Hubble residuals and host galaxy mass. Since the FMR is nearly constant between z=2 and the present, use of the FMR along with light curve width and color should provide a robust distance measurement method that minimizes systematic errors.
1212.4905
Calibrating [OII] star-formation rates at z>1 from dual H\alpha-[OII] imaging from HiZELS
Hayashi, Sorbal, Best, Smail, Kodama
Investigate the relationship between H\alpha\ and [OII](\lambda 3727) emission in faint SF galaxies at z=1.47 with dust uncorrected SFRs sown to 1.4Msun/yr, using data in 2 narrow-bands. ... Important to take into account that the relations for the dust correction which are derived using H\alpha\ emitter samples, and frequently used in many studies of high-z galaxies, may overestimate the intrinsic SFRs of [OII]-selected galaxies, and that surveys of [OII] emission galaxies are likely to miss dusty populations.
1212.5018
A novel approach in the WIMP quest: cross-correlation of gamma-ray anisotropies and cosmic shear
Camera, Fornasa, Fornengo, Regis
DM structures are responsible for bending of light, and those same objects can emit gamma-rays, either because they host astrophysical sources (AGN or SF galaxies) or directly by DM annihilations (or decays). Such gamma-rays should therefore exhibit strong correlation with the cosmic shear signal. In this Letter, we compute the cross-correlation angular PS of cosmic shear and gamma-rays produced by the annihilation/decay of WIMP DM, as well as from astrophysical sources. Show that this observable provides novel information on the composition of the EGB (extra-galactic gamma-ray BG), since the amplitude and shape of the cross-correlation signal strongly depends on which class of source is responsible for the gamma-ray emission. If the DM contribution to the EGB is significant (at least in a definite energy range), although compatible with current observational bounds, its strong correlation with the cosmic shear makes such signal potentially detectable by combining Fermi-LAT data with forthcoming galaxy surveys, like DES and Euclid. At the same time, the same signal would demonstrate that the WL observables are indeed due to particle DM matter, and not to possible modifications of GR.
1212.5076
Measuring the dark matter halo mass of X-ray AGN at z~1 using photometric redshifts
Mountrichas, .. Finoguenov, ... Coil, ... Newman et al
Infer the bias and DM halo mass of moderate luminosity X-ray AGN at z~1 via their X-correlation function with galaxies. In contrast to standard cross-correlation function estimators, present a method that requires spectroscopy only for the AGN and uses photometric redshift probability distribution functions for galaxies to determine the projected real-space AGN/galaxy cross-correlation function. The estimated DM halo mass of X-ray AGN in the combined AEGIS, COSMOS and ECDFS fields is ~13 Msun/h, in agreement with previous studies at similar redshift and luminosity ranges. Removing from the sample the 5% of the AGN associated with x-ray selected groups results in a reduction by about 0.5 dex in the inferred AGN DM halo mass. The distribution of AGN in DM halo mass is therefore skewed and the bulk of the population lives in moderate mass haloes. This result favors cold gas accretion as the main channel of SMBH growth for most X-ray AGN.
1212.5077
Helioseismology: a fantastic tool to probe the interior of the Sun
Di Mauro
The study of global solar oscillations has proved to be an extremely powerful tool for the investigation of the internal structure and dynamics of the Sun. Studies of time changes in frequency observations of solar oscillations from helioseismology experiments on Earth and in space have shown, for example, that the Sun's shape varies over solar cycle timescales. In particular, far-reaching inferences about the Sun have been obtained by applying inversion techniques to observations of frequencies of oscillations. The results, so far, have shown that the solar structure is remarkably close to the predictions of the standard solar model and, recently, that the near-surface region can be probed with sufficiently high spatial resolution as to allow investigations of the equation of state and of the solar envelope He abundance. The same helioseismic inversion methods can be applied to the rotational frequency splittings to deduce with high accuracy the internal rotation velocity of the Sun, as function of radius and latitude. This also allows us to study some global astrophysical properties of the Sun, such as the angular momentum, the gravitational quadrupole moment and the effect of distortion induced on the surface (oblateness). The helioseismic approach and what we have learnt from it during the last decades about the interior of the Sun are reviewed here.
1212.5092
Spherical collapse model with shear and angular momentum in dark energy cosmologies
Del Popolo, Pace, Lima
How shear and angular momentum modify typical parameters of the spherical collapse model in DE dominated universes. Study the linear density threshold for collapse delta_c and the virial overdensity Delta_V for several DE models and its influence on the cumulative mass function. With the introduction of shear and rotation terms, the parameters of the spherical collapse model are now mass-dependent. The results of the paper show, as expected, that the new terms considered in the spherical collapse model oppose the collapse of perturbations on the galactic scale giving rise to higher values of the linear overdensity parameter with respect to the non-rotating case. Find a similar effect also for the virial overdensity parameter. For what concerns the mass function, find that its high mass tail is suppressed, while the low mass tail is slightly affected except in some cases.
1212.5159
A study on the chemical properties of blue compact dwarf galaxies
Zhao, Gao, Gu
Studies on the gaseous and chemical properties of a 53-sample blue compact dwarf galaxies (BCDs). Correlations among O abundance, M*, M_gas, M_baryon, and f_gas are present for both E- and I-type BCDs, which are classified and show elliptical and irregular outer haloes, respectively. These correlations of I-type BCDs show similar slopes to those of E-type ones. However, in general, E-type BCDs are more gas-poor and metal-rich than I-type ones at a given baryonic mass. Based on these results, suggest that E-type BCDs, at least a part of them, and I-type ones might be likely at different evolutionary phases and/or having different progenitors. Investigation of the correlation between O abundance and gas fraction shows that BCDs appear to have not evolved as isolated systems, but to have experienced some gas flows and/or mergers.
1212.5222
A new multi-field determination of the galaxy luminosity function at z=7-9 incorporating the 2012 Hubble ultradeep field imaging
McLure, et al
Results strengthen suggestions that the evolution at z>7 is more akin to 'density evolution' than the apparent 'luminosity evolution' seen at z~5-7. Provide the first meaningful information on the LF at z~9, explore alternative extrapolations to higher z, and consider the implications for the evolution of UV luminosity density. Finally, provide catalogues for the 100 most robust 6.5<z<11.9 galaxies in the HUDF used in the analysis. DIscuss results in the context of earlier work and the results of an independent analysis of the UDF12 data based on color-color selection.
1212.5225
Nine-year wilkinson microwave anisotropy probe (WMAP) observations: final maps and results
Bennett, ... Halpern, Komatsu, .. Page, Spergel, .. Dunkley, Kogut, Limon, ... Tucker, Wright et al
Findal 9 year maps and basic results from WMAP mission. Full sky T maps, processed to reduce the asymmetry of the effective beams. Temperature and polariation sky maps examined to separate CMB anisotropy from FG emission, and both types of signals are analyzed in detail. Combine with finer scale CMB, BAO, and H0 constant measurements, find that BBN is well supported and no compelling evidence for a non-standard number of neutrino species (3.26pm0.35). Model fit also implies that the age of the universe is 13.772pm0.059 Gyr, and the fit Hubble constants H0=6932pm0.8 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 early by WMAP now has high statistical significance (n_s = 0.9608 pm 0.0080); and the universe is close to flat/Euclidean, Omega_k = -0.0027 pm 0.0039. Overall, the WMAP mission has resulted in a reduction of the cosmological parameter volume by a factor of 68000 for the standard 6 parameter LCDM model, based on CMB data alone. For a model including tensors, the allowed 7-parameter volume has been reduced by a factor 117000. 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 LCDM model and its precise and accurate parameters rooted in WMAP data stands as the standard model of cosmology. [What is sigma_8?]
1212.5226
Nine-year Wilkinson microwave anisotropy probe (WMAP) observations: cosmological parameter results
Hinshaw, et al
WMAP data alone are remarkable well fit by a six-parameter LCDM model. When combined with high-l CMB anisotrpy, BAO, H0, the densities (bhp, ch2, and L) are each determined to a precision of ~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 5 year WMAP data. .. Compare recent PLANCK measurements of SZ effect with WMAP7, show their mutual agreement. 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.
The merger rates and sizes of galaxies across the peak epoch of star formation from the HiZELS survey
Stott, et al
HiZELS Narrow-band H-alpha survey, combined with CANDELS, UKIDSS and WIRDS NIR imaging, to invesitgate the morphologies, merger rates and sizes of a sample of H-alpha emitting galaxies in the 0.40<z<2.23, an epoch encompassing the rise to the peak of the SFR density. Merger rates are estimated from space- and ground-based imaging using the M20 coefficient [what's that?]. To account for the increase in the specific SFR (sSFR) of the SF 'main-sequence' with z, normalize the SFR of galaxies at each epoch to the typical value derived from the H-alpha LF. Once this trend in sSFR is removed, see no evidence for an increase in the number density of SF galaxies or merger rate with redshift. Conclude that neither is the main driver of the enhanced SFR density at z=1-2, with secular processes such as instabilities within efficiently fueled, gas-rich discs or multiple minor mergers the most likely alternatives. However, find that 40-50% of starburst galaxies, those with enhanced specific SF at their epoch, are major mergers and this fraction is z independent. Finally, find that the typical size of a SF galaxy of a given mass does not evolve across the redshift range considered, suggesting a universal size-mass relation. Taken in combination, these results indicate a SF galaxy population that is statistically similar in physical size, merger rate and mass over the 6 Gyr covered in this study, despite the increase in typical sSFR.
1212.4835
Probing high-redshift galaxy formation at the highest luminosities: new insights from DEIMOS spectroscopy
Lee, Dey, Cooper, Reddy, Jannuzi
Most UV-luinous SF galaxies at 3.2,z<4.6; sample contains L*<L<7L*, largest sample to date at these z. Clean selection of photometric candidates validated. Fraction of Lya emitters increases with decreasing UV luminosity. Find strong evidence of large-scale outflows, transporting the neutral/ionized gas in the ISM away from the galaxy. Galaxies exhibiting both interstellar absorption and Lya emission lines show a significant velocity offset between the 2 features (200-1140 km/s). Find tentative evidence that this measure of the outflow velocity increases with UV luminosity and/or stellar mass. The luminosity- and mass-dependent outflow strengths suggest that the efficiency of feedback and enrichment of the surrounding medium depend on these parameters. Present composite spectra of the absorption-line-only and Lya-emitting subsets of the UV luminous galaxies at z~3.7. The composite spectra are similar to those of lower-z and lower-luminosity LBG samples, but with some subtle differences. Analysis of the composite spectra suggest that the UV luminous LBGs at z~3.7 may have a higher covering fraction of absorbing gas, and may be older than their lower-z and lower-luminosity counterparts. In addition, 5 galaxies discover that belong to a massive over density at z=3.78. 2 galaxies each show 2 distinct sets of interstellar absorption features. The latter may be a sign of a final stage of major merger, or clumpy disk formation. Their presence implies that frequency of such sources among the luminous z~3.7 LBGs may be an order of magnitude higher than in lower redshift and lower luminosity samples.
1212.4844
The cosmic MeV neutrino background as a laboratory for black hole formation
Yuksel, Kistler
Calculations of the cosmic rate of corse collapses, and the associated neutrino flux, commonly assume that a fixed fraction of massive stars collapse to black holes. Argue that recent results suggest that this fraction instead increases with z. With relatively more stars vanishing as "unnovae" in the distant universe, the detectability of the cosmic MeV neutrino background is improved due to their hotter neutrino spectrum, and expectations for supernova surveys are reduced. We conclude that neutrino detectors, after the flux from normal SNe is isolated via either improved modeling or the next Galactic SN, can probe the conditions and history of BH formation.
1212.4848
The fundamental metallicity relation reduces type Ia SN Hubble residuals more than host mass alone
Hayden, Gupta, Garnavich, Mannucci, Nichol, Sako
* FMR: mass-metllicity-SFR relation.
SNIa Hubble residuals have been shown to correlate with host galaxy mass, imposing a major obstacle for their use in measuring DE properties. Here, calibrate the fundamental metallicity relation (FMR) of Mannucci+ (2010) for host mass and SFR measured from broad-band colors alone. Apply the FMR to the large number of hosts from the SSS-II sample of GUpta+ 2011 and find that the scatter in the Hubble residuals is significantly reduced when compared with using only stellar mass (or the mass-metallicity relation) as a fit parameter. Calibration of the FMR is restricted to only SF galaxies and in the Hubble residual calculation include only hosts with log(SFR)>-2. Results strongly suggest that metallicity is the underlying source of the correlation between Hubble residuals and host galaxy mass. Since the FMR is nearly constant between z=2 and the present, use of the FMR along with light curve width and color should provide a robust distance measurement method that minimizes systematic errors.
1212.4905
Calibrating [OII] star-formation rates at z>1 from dual H\alpha-[OII] imaging from HiZELS
Hayashi, Sorbal, Best, Smail, Kodama
Investigate the relationship between H\alpha\ and [OII](\lambda 3727) emission in faint SF galaxies at z=1.47 with dust uncorrected SFRs sown to 1.4Msun/yr, using data in 2 narrow-bands. ... Important to take into account that the relations for the dust correction which are derived using H\alpha\ emitter samples, and frequently used in many studies of high-z galaxies, may overestimate the intrinsic SFRs of [OII]-selected galaxies, and that surveys of [OII] emission galaxies are likely to miss dusty populations.
1212.5018
A novel approach in the WIMP quest: cross-correlation of gamma-ray anisotropies and cosmic shear
Camera, Fornasa, Fornengo, Regis
DM structures are responsible for bending of light, and those same objects can emit gamma-rays, either because they host astrophysical sources (AGN or SF galaxies) or directly by DM annihilations (or decays). Such gamma-rays should therefore exhibit strong correlation with the cosmic shear signal. In this Letter, we compute the cross-correlation angular PS of cosmic shear and gamma-rays produced by the annihilation/decay of WIMP DM, as well as from astrophysical sources. Show that this observable provides novel information on the composition of the EGB (extra-galactic gamma-ray BG), since the amplitude and shape of the cross-correlation signal strongly depends on which class of source is responsible for the gamma-ray emission. If the DM contribution to the EGB is significant (at least in a definite energy range), although compatible with current observational bounds, its strong correlation with the cosmic shear makes such signal potentially detectable by combining Fermi-LAT data with forthcoming galaxy surveys, like DES and Euclid. At the same time, the same signal would demonstrate that the WL observables are indeed due to particle DM matter, and not to possible modifications of GR.
1212.5076
Measuring the dark matter halo mass of X-ray AGN at z~1 using photometric redshifts
Mountrichas, .. Finoguenov, ... Coil, ... Newman et al
Infer the bias and DM halo mass of moderate luminosity X-ray AGN at z~1 via their X-correlation function with galaxies. In contrast to standard cross-correlation function estimators, present a method that requires spectroscopy only for the AGN and uses photometric redshift probability distribution functions for galaxies to determine the projected real-space AGN/galaxy cross-correlation function. The estimated DM halo mass of X-ray AGN in the combined AEGIS, COSMOS and ECDFS fields is ~13 Msun/h, in agreement with previous studies at similar redshift and luminosity ranges. Removing from the sample the 5% of the AGN associated with x-ray selected groups results in a reduction by about 0.5 dex in the inferred AGN DM halo mass. The distribution of AGN in DM halo mass is therefore skewed and the bulk of the population lives in moderate mass haloes. This result favors cold gas accretion as the main channel of SMBH growth for most X-ray AGN.
1212.5077
Helioseismology: a fantastic tool to probe the interior of the Sun
Di Mauro
The study of global solar oscillations has proved to be an extremely powerful tool for the investigation of the internal structure and dynamics of the Sun. Studies of time changes in frequency observations of solar oscillations from helioseismology experiments on Earth and in space have shown, for example, that the Sun's shape varies over solar cycle timescales. In particular, far-reaching inferences about the Sun have been obtained by applying inversion techniques to observations of frequencies of oscillations. The results, so far, have shown that the solar structure is remarkably close to the predictions of the standard solar model and, recently, that the near-surface region can be probed with sufficiently high spatial resolution as to allow investigations of the equation of state and of the solar envelope He abundance. The same helioseismic inversion methods can be applied to the rotational frequency splittings to deduce with high accuracy the internal rotation velocity of the Sun, as function of radius and latitude. This also allows us to study some global astrophysical properties of the Sun, such as the angular momentum, the gravitational quadrupole moment and the effect of distortion induced on the surface (oblateness). The helioseismic approach and what we have learnt from it during the last decades about the interior of the Sun are reviewed here.
1212.5092
Spherical collapse model with shear and angular momentum in dark energy cosmologies
Del Popolo, Pace, Lima
How shear and angular momentum modify typical parameters of the spherical collapse model in DE dominated universes. Study the linear density threshold for collapse delta_c and the virial overdensity Delta_V for several DE models and its influence on the cumulative mass function. With the introduction of shear and rotation terms, the parameters of the spherical collapse model are now mass-dependent. The results of the paper show, as expected, that the new terms considered in the spherical collapse model oppose the collapse of perturbations on the galactic scale giving rise to higher values of the linear overdensity parameter with respect to the non-rotating case. Find a similar effect also for the virial overdensity parameter. For what concerns the mass function, find that its high mass tail is suppressed, while the low mass tail is slightly affected except in some cases.
1212.5159
A study on the chemical properties of blue compact dwarf galaxies
Zhao, Gao, Gu
Studies on the gaseous and chemical properties of a 53-sample blue compact dwarf galaxies (BCDs). Correlations among O abundance, M*, M_gas, M_baryon, and f_gas are present for both E- and I-type BCDs, which are classified and show elliptical and irregular outer haloes, respectively. These correlations of I-type BCDs show similar slopes to those of E-type ones. However, in general, E-type BCDs are more gas-poor and metal-rich than I-type ones at a given baryonic mass. Based on these results, suggest that E-type BCDs, at least a part of them, and I-type ones might be likely at different evolutionary phases and/or having different progenitors. Investigation of the correlation between O abundance and gas fraction shows that BCDs appear to have not evolved as isolated systems, but to have experienced some gas flows and/or mergers.
1212.5222
A new multi-field determination of the galaxy luminosity function at z=7-9 incorporating the 2012 Hubble ultradeep field imaging
McLure, et al
Results strengthen suggestions that the evolution at z>7 is more akin to 'density evolution' than the apparent 'luminosity evolution' seen at z~5-7. Provide the first meaningful information on the LF at z~9, explore alternative extrapolations to higher z, and consider the implications for the evolution of UV luminosity density. Finally, provide catalogues for the 100 most robust 6.5<z<11.9 galaxies in the HUDF used in the analysis. DIscuss results in the context of earlier work and the results of an independent analysis of the UDF12 data based on color-color selection.
1212.5225
Nine-year wilkinson microwave anisotropy probe (WMAP) observations: final maps and results
Bennett, ... Halpern, Komatsu, .. Page, Spergel, .. Dunkley, Kogut, Limon, ... Tucker, Wright et al
Findal 9 year maps and basic results from WMAP mission. Full sky T maps, processed to reduce the asymmetry of the effective beams. Temperature and polariation sky maps examined to separate CMB anisotropy from FG emission, and both types of signals are analyzed in detail. Combine with finer scale CMB, BAO, and H0 constant measurements, find that BBN is well supported and no compelling evidence for a non-standard number of neutrino species (3.26pm0.35). Model fit also implies that the age of the universe is 13.772pm0.059 Gyr, and the fit Hubble constants H0=6932pm0.8 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 early by WMAP now has high statistical significance (n_s = 0.9608 pm 0.0080); and the universe is close to flat/Euclidean, Omega_k = -0.0027 pm 0.0039. Overall, the WMAP mission has resulted in a reduction of the cosmological parameter volume by a factor of 68000 for the standard 6 parameter LCDM model, based on CMB data alone. For a model including tensors, the allowed 7-parameter volume has been reduced by a factor 117000. 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 LCDM model and its precise and accurate parameters rooted in WMAP data stands as the standard model of cosmology. [What is sigma_8?]
1212.5226
Nine-year Wilkinson microwave anisotropy probe (WMAP) observations: cosmological parameter results
Hinshaw, et al
WMAP data alone are remarkable well fit by a six-parameter LCDM model. When combined with high-l CMB anisotrpy, BAO, H0, the densities (bhp, ch2, and L) are each determined to a precision of ~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 5 year WMAP data. .. Compare recent PLANCK measurements of SZ effect with WMAP7, show their mutual agreement. 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.
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