The Completed SDSS-IV Extended Baryon Oscillation Spectroscopic Survey: Baryon Acoustic Oscillations with Lyα Forests

Bourboux, Hélion du Mas des; Rich, J.; Font-Ribera, Andreu; Agathe, Victoria de Sainte; Farr, James; Etourneau, Thomas; Goff, J. M. Le; Cuceu, Andrei; Balland, C.; Bautista, Julian; Blomqvist, Michael; Brinkmann, J.; Brownstein, Joel R.; Chabanier, Solène; Chaussidon, Edmond; Dawson, Kyle; González‐Morales, Alma X.; Guy, J.; Lyke, Brad W.; Macorra, Axel de la; Mueller, Eva Maria; Myers, Adam D.; Nitschelm, Christian; Gutiérrez, Andrea Muñoz; Palanque-Delabrouille, N.; Parker, J.R.; Percival, Will J.; Pérez-Ràfols, Ignasi; Petitjean, P.; Pieri, Matthew M.; Ravoux, Corentin; Rossi, Graziano; Schneider, Donald P.; Seo, Hee-Jong; Slosar, Anže; Stermer, Julianna; Vivek, M.; Yèche, Ch; Youles, Samantha

doi:10.3847/1538-4357/abb085

“…Baryon acoustic oscillations (BAO): The BAO is another important cosmological probe, which can trace expanding spherical wave of baryonic perturbations from acoustic oscillations at recombination time through the largescale structure correlation function, which displays a peak around 150 h −1 Mpc. We use BAO measurements from Sloan Digital Sky Survey (SDSS) III DR-12 at three effective binned redshifts z = 0.38, 0.51 and 0.61, reported in [3], the clustering of the SDSS-IV extended Baryon Oscillation Spectroscopic Survey DR14 quasar sample at four effective binned redshifts z = 0.98, 1.23, 1,52 and 1.94, reported in [79], and the high-redshift Lyman-α measurements at z = 2.33 and z = 2.4 reported in [80] and [81], respectively. Note that the observations are presented in terms of Supernovae Type Ia (SN): The SN traditionally have been one of the most important astrophysical tools in establishing the so-called standard cosmological model.…”

Section: Data Setsmentioning

confidence: 92%

“…Thus, with the possibility of a preference for negative energy density values at high z, it is argued that the Ly-α data at z ∼ 2.34 can be described by a non-monotonic evolution in H (z) function, which is difficult to achieve in any model with non-negative DE density [105]. Note that in our analysis, we are taking into account the high z Lymanα measurements reported in [80] and [81]. It is possible to achieve X < 0 at high z when the cosmological gravitational coupling strength gets weaker with increasing z [106,107].…”

Section: The Lagrangianmentioning

confidence: 99%

Measurements of $$H_0$$ and reconstruction of the dark energy properties from a model-independent joint analysis

Bonilla

¹

,

Kumar

²

,

Nunes

³

2021

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Gaussian processes (GP) provide an elegant and model-independent method for extracting cosmological information from the observational data. In this work, we employ GP to perform a joint analysis by using the geometrical cosmological probes such as Supernova Type Ia (SN), Cosmic chronometers (CC), Baryon Acoustic Oscillations (BAO), and the H0LiCOW lenses sample to constrain the Hubble constant $$H_0$$ H 0 , and reconstruct some properties of dark energy (DE), viz., the equation of state parameter w, the sound speed of DE perturbations $$c^2_s$$ c s 2 , and the ratio of DE density evolution $$X = \rho _\mathrm{de}/\rho _\mathrm{de,0}$$ X = ρ de / ρ de , 0 . From the joint analysis SN+CC+BAO+H0LiCOW, we find that $$H_0$$ H 0 is constrained at 1.1% precision with $$H_0 = 73.78 \pm 0.84\ \hbox {km}\ \hbox {s}^{-1}\,\hbox {Mpc}^{-1}$$ H 0 = 73.78 ± 0.84 km s - 1 Mpc - 1 , which is in agreement with SH0ES and H0LiCOW estimates, but in $$\sim 6.2 \sigma $$ ∼ 6.2 σ tension with the current CMB measurements of $$H_0$$ H 0 . With regard to the DE parameters, we find $$c^2_s < 0$$ c s 2 < 0 at $$\sim 2 \sigma $$ ∼ 2 σ at high z, and the possibility of X to become negative for $$z > 1.5$$ z > 1.5 . We compare our results with the ones obtained in the literature, and discuss the consequences of our main results on the DE theoretical framework.

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“…The BAO data included the recently released Date Release (DR) 16 of the extended Baryon Oscillation Spectroscopic Survey (eBOSS) 50 that includes BAO and redshift space distortions measurements at multiple redshifts from the samples of Luminous Red Galaxies (LRGs), Emission Line Galaxies (ELGs), clustering quasars (QSOs), and the Lyman-α forest. We use the BAO measurement from the fullshape auto-and cross-power spectrum of the eBOSS, LRGs, and ELGs 51,52 , the BAO measurement from the QSO sample 53 , and from the Lyman-α forest sample 54 . We combine these with the low-z BAO measurements by 6dF 55 and the SDSS DR7 main Galaxy sample 56 .…”

Section: Methodsmentioning

confidence: 99%

“…To demonstrate how the slope of the lines changes with redshift, we show two lines corresponding to the SDSS measurements of θ BAO ? at z = 0.51 and z = 1.554 at a fixed Ω m h 2 = 0.143. The gray band shows the 68% and 95% CL determination of the Hubble constant by SH0ES.…”

mentioning

confidence: 99%

Why reducing the cosmic sound horizon alone can not fully resolve the Hubble tension

Jedamzik

¹

,

Pogosian

²

,

Zhao

³

2021

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The mismatch between the locally measured expansion rate of the universe and the one inferred from the cosmic microwave background measurements by Planck in the context of the standard ΛCDM, known as the Hubble tension, has become one of the most pressing problems in cosmology. A large number of amendments to the ΛCDM model have been proposed in order to solve this tension. Many of them introduce new physics, such as early dark energy, modifications of the standard model neutrino sector, extra radiation, primordial magnetic fields or varying fundamental constants, with the aim of reducing the sound horizon at recombination r⋆. We demonstrate here that any model which only reduces r⋆ can never fully resolve the Hubble tension while remaining consistent with other cosmological datasets. We show explicitly that models which achieve a higher Hubble constant with lower values of matter density Ωmh2 run into tension with the observations of baryon acoustic oscillations, while models with larger Ωmh2 develop tension with galaxy weak lensing data.

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“…The redshifts are estimated using the REDVSBLUE 1 principal component analysis algorithm described in Lyke et al (2020), with 95 per cent completeness and 2 per cent false-positive rate. The main quasar sample spans the redshift range of 0.8 < z < 2.2 and is used for various cosmological analyses of the BAO and RSD features (du Mas des Bourboux et al 2020;Neveux et al 2020;Smith et al 2020;Hou et al 2021). Additionally, the high-z quasars with 2.2 < z < 3.5 are employed for measuring the BAO signal in the Ly α forest (Blomqvist et al 2019;Chabanier et al 2019;de Sainte Agathe et al 2019).…”

Section: Eboss Dr16 Quasarsmentioning

confidence: 99%

Primordial non-Gaussianity from the completed SDSS-IV extended Baryon Oscillation Spectroscopic Survey – I: Catalogue preparation and systematic mitigation

Rezaie

¹

,

Ross

²

,

Seo

³

et al. 2021

Monthly Notices of the Royal Astronomical Society

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We investigate the large-scale clustering of the final spectroscopic sample of quasars from the recently completed extended Baryon Oscillation Spectroscopic Survey (eBOSS). The sample contains 343708 objects in the redshift range 0.8 < z < 2.2 and 72667 objects with redshifts 2.2 < z < 3.5, covering an effective area of 4699 deg2. We develop a neural network-based approach to mitigate spurious fluctuations in the density field caused by spatial variations in the quality of the imaging data used to select targets for follow-up spectroscopy. Simulations are used with the same angular and radial distributions as the real data to estimate covariance matrices, perform error analyses, and assess residual systematic uncertainties. We measure the mean density contrast and cross-correlations of the eBOSS quasars against maps of potential sources of imaging systematics to address algorithm effectiveness, finding that the neural network-based approach outperforms standard linear regression. Stellar density is one of the most important sources of spurious fluctuations, and a new template constructed using data from the Gaia spacecraft provides the best match to the observed quasar clustering. The end-product from this work is a new value-added quasar catalogue with the improved weights to correct for nonlinear imaging systematic effects, which will be made public. Our quasar catalogue is used to measure the local-type primordial non-Gaussianity in our companion paper, Mueller et al. in preparation.

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The Completed SDSS-IV Extended Baryon Oscillation Spectroscopic Survey: Baryon Acoustic Oscillations with Lyα Forests

Cited by 282 publications

References 102 publications

Measurements of $$H_0$$ and reconstruction of the dark energy properties from a model-independent joint analysis

Measurements of $$H_0$$ and reconstruction of the dark energy properties from a model-independent joint analysis

Why reducing the cosmic sound horizon alone can not fully resolve the Hubble tension

Primordial non-Gaussianity from the completed SDSS-IV extended Baryon Oscillation Spectroscopic Survey – I: Catalogue preparation and systematic mitigation

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