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Register a new userUnified galaxy power spectrum measurements from 6dFGS, BOSS, and eBOSS
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We make use of recent developments in the analysis of galaxy redshift surveys to present an easy to use matrix-based analysis framework for the galaxy power spectrum multipoles, including wide-angle effects and the survey window function. We employ this framework to derive the deconvolved power spectrum multipoles of 6dFGS DR3, BOSS DR12 and the eBOSS DR16 quasar sample. As an alternative to the standard analysis, the deconvolved power spectrum multipoles can be used to perform a data analysis agnostic of survey specific aspects, like the window function. We show that in the case of the BOSS dataset, the Baryon Acoustic Oscillation (BAO) analysis using the deconvolved power spectra results in the same likelihood as the standard analysis. To facilitate the analysis based on both the convolved and deconvolved power spectrum measurements, we provide the window function matrices, wide-angle matrices, covariance matrices and the power spectrum multipole measurements for the datasets mentioned above. Together with this paper we publish a code{Python}-based toolbox to calculate the different analysis components. The appendix contains a detailed user guide with examples for how a cosmological analysis of these datasets could be implemented. We hope that our work makes the analysis of galaxy survey datasets more accessible to the wider cosmology community.
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We present cosmological parameter measurements from the effective field theory-based full-shape analysis of the power spectrum of emission line galaxies (ELGs). First, we perform extensive tests on simulations and determine appropriate scale cuts for the perturbative description of the ELG power spectrum. We study in detail non-linear redshift-space distortions (fingers-of-God) for this sample and show that they are somewhat weaker than those of luminous red galaxies. This difference is not significant for current data, but may become important for future surveys like Euclid/DESI. Then we analyze recent measurements of the ELG power spectrum from the extended Baryon acoustic Oscillation Spectroscopic Survey (eBOSS) within the $ uLambda$CDM model. Combined with the BBN baryon density prior, the ELG pre- and post-reconstructed power spectra alone constrain the matter density $Omega_m=0.257_{-0.045}^{+0.031}$, the current mass fluctuation amplitude $sigma_8=0.571_{-0.076}^{+0.052}$, and the Hubble constant $H_0=84.5_{-7}^{+5.8}$ km/s/Mpc (all at 68% CL). Combining with other full-shape and BAO data we measure $Omega_m=0.321_{-0.016}^{+0.013}$, $sigma_8=0.662_{-0.042}^{+0.038}$, and $H_0=68.9_{-1.1}^{+1}$ km/s/Mpc. The total neutrino mass is constrained to be $M_{rm tot}<0.64$ eV (95% CL) from the BBN, full-shape and BAO data only.
We have developed two independent methods to measure the one-dimensional power spectrum of the transmitted flux in the Lyman-$alpha$ forest. The first method is based on a Fourier transform, and the second on a maximum likelihood estimator. The two methods are independent and have different systematic uncertainties. The determination of the noise level in the data spectra was subject to a novel treatment, because of its significant impact on the derived power spectrum. We applied the two methods to 13,821 quasar spectra from SDSS-III/BOSS DR9 selected from a larger sample of over 60,000 spectra on the basis of their high quality, large signal-to-noise ratio, and good spectral resolution. The power spectra measured using either approach are in good agreement over all twelve redshift bins from $<z> = 2.2$ to $<z> = 4.4$, and scales from 0.001 $rm(km/s)^{-1}$ to $0.02 rm(km/s)^{-1}$. We determine the methodological and instrumental systematic uncertainties of our measurements. We provide a preliminary cosmological interpretation of our measurements using available hydrodynamical simulations. The improvement in precision over previously published results from SDSS is a factor 2--3 for constraints on relevant cosmological parameters. For a $Lambda$CDM model and using a constraint on $H_0$ that encompasses measurements based on the local distance ladder and on CMB anisotropies, we infer $sigma_8 =0.83pm0.03$ and $n_s= 0.97pm0.02$ based on ion{H}{i} absorption in the range $2.1<z<3.7$.
The most commonly used estimators of the anisotropic galaxy power spectrum employ Fast Fourier transforms, and rely on a specific choice of the line-of-sight that breaks the symmetry between the galaxy pair. This leads to wide-angle effects, including the presence of odd power spectrum multipoles like the dipole ($ell = 1$) and octopole ($ell = 3$). In Fourier-space these wide-angle effects also couple to the survey window function. We present a self-consistent framework extending the commonly used window function treatment to include the wide-angle effects. We show that our framework can successfully model the wide-angle effects in the BOSS DR12 dataset. We present estimators for the odd power spectrum multipoles and, detect these multipoles in BOSS DR12 with high significance. Understanding the impact of the wide-angle effects on the power spectrum multipoles is essential for many cosmological observables like primordial non-Gaussianity and the detection of General Relativistic effects and represents a potential systematic for measurements of Baryon Acoustic Oscillations and redshift-space distortions.
We constrain cosmological parameters by analysing the angular power spectra of the Baryon Oscillation Spectroscopic Survey DR12 galaxies, a spectroscopic follow-up of around 1.3 million SDSS galaxies over 9,376 deg$^2$ with an effective volume of $sim 6.5$ (Gpc $h^{-1}$)$^3$ in the redshift range $0.15 leq z < 0.80$. We split this sample into 13 tomographic bins ($Delta z = 0.05$); angular power spectra were calculated using a Pseudo-$C_{ell}$ estimator, and covariance matrices were estimated using log-normal simulated maps. Cosmological constraints obtained from these data were combined with constraints from Planck CMB experiment as well as the JLA supernovae compilation. Considering a $w$CDM cosmological model measured on scales up to $k_{max} = 0.07h$ Mpc$^{-1}$, we constrain a constant dark energy equation-of-state with a $sim 4%$ error at the 1-$sigma$ level: $w_0 = -0.993^{+0.046}_{-0.043}$, together with $Omega_m = 0.330pm 0.012$, $Omega_b = 0.0505 pm 0.002$, $S_8 equiv sigma_8 sqrt{Omega_m/0.3} = 0.863 pm 0.016$, and $h = 0.661 pm 0.012$. For the same combination of datasets, but now considering a $Lambda$CDM model with massive neutrinos and the same scale cut, we find: $Omega_m = 0.328 pm 0.009$, $Omega_b = 0.05017^{+0.0009}_{-0.0008}$, $S_8 = 0.862 pm 0.017$, and $h = 0.663^{+0.006}_{-0.007}$ and a 95% credible interval (CI) upper limit of $sum m_{ u} < 0.14$ eV for a normal hierarchy. These results are competitive if not better than standard analyses with the same dataset, and demonstrate this should be a method of choice for future surveys, opening the door for their full exploitation in cross-correlations probes.
We present constraints on masses of active and sterile neutrinos. We use the one-dimensional Ly$alpha$-forest power spectrum from the Baryon Oscillation Spectroscopic Survey (BOSS) of the Sloan Digital Sky Survey (SDSS-III) and from the VLT/XSHOOTER legacy survey (XQ-100). In this paper, we present our own measurement of the power spectrum with the publicly released XQ-100 quasar spectra. Fitting Ly$alpha$ data alone leads to cosmological parameters in excellent agreement with the values derived independently from Planck 2015 Cosmic Microwave Background (CMB) data. Combining BOSS and XQ-100 Ly$alpha$ power spectra, we constrain the sum of neutrino masses to $sum m_ u < 0.8$ eV (95% C.L). With the addition of CMB data, this bound is tightened to $sum m_ u < 0.14$ eV (95% C.L.). With their sensitivity to small scales, Ly$alpha$ data are ideal to constrain $Lambda$WDM models. Using XQ-100 alone, we issue lower bounds on pure dark matter particles: $m_X gtrsim 2.08 : rm{keV}$ (95% C.L.) for early decoupled thermal relics, and $m_s gtrsim 10.2 : rm{keV}$ (95% C.L.) for non-resonantly produced right-handed neutrinos. Combining the 1D Ly$alpha$ forest power spectrum measured by BOSS and XQ-100, we improve the two bounds to $m_X gtrsim 4.17 : rm{keV}$ and $m_s gtrsim 25.0 : rm{keV}$ (95% C.L.). The $3~sigma$ bound shows a more significant improvement, increasing from $m_X gtrsim 2.74 : rm{keV}$ for BOSS alone to $m_X gtrsim 3.10 : rm{keV}$ for the combined BOSS+XQ-100 data set. Finally, we include in our analysis the first two redshift bins ($z=4.2$ and $z=4.6$) of the power spectrum measured with the high-resolution HIRES/MIKE spectrographs. The addition of HIRES/MIKE power spectrum allows us to further improve the two limits to $m_X gtrsim 4.65 : rm{keV}$ and $m_s gtrsim 28.8 : rm{keV}$ (95% C.L.).
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