Impact of systematics on cosmological parameters from future galaxy cluster surveys

Galaxy clusters are a recent cosmological probe. The precision and accuracy of the cosmological parameters inferred from these objects are affected by the knowledge of cluster physics, entering the analysis through the mass-observable scaling relations, and the theoretical description of their mass and redshift distribution, modelled by the mass function. In this work we forecast the impact of different modelling of these ingredients for clusters detected by future optical and near-IR surveys. We consider the standard cosmological scenario and the case with a time-dependent equation of state for dark energy. We analyse the effect of increasing precision on the scaling relation calibration, finding improved constraints on the cosmological parameters. This higher precision exposes the impact of the mass function evaluation, which is a subdominant source of systematics for current data. We compare two different evaluations for the mass function. In both cosmological scenarios the use of different mass functions leads to biases in the parameter constraints. For the ΛCDM model, we find a 1.6σ shift in the (Ωm, σ8) parameter plane and a discrepancy of ∼7σ for the redshift evolution of the scatter of the scaling relations. For the scenario with a time-evolving dark energy equation of state, the assumption of different mass functions results in a ∼8σ tension in the w0 parameter. These results show the impact, and the necessity for a precise modelling, of the interplay between the redshift evolution of the mass function and of the scaling relations in the cosmological analysis of galaxy clusters.

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Observing Galaxy Clusters with eROSITA: Simulations

Acta Polytechnica ◽

10.14311/1466 ◽

2011 ◽

Vol 51 (6) ◽

Author(s):

J. Hölzl ◽

J. Wilms ◽

I. Kreykenbohm ◽

Ch. Schmid ◽

Ch. Grossberger ◽

...

Keyword(s):

Monte Carlo ◽

Dark Matter ◽

Dark Energy ◽

Galaxy Clusters ◽

Cosmological Parameters ◽

Mass Function ◽

Angular Diameter ◽

Monte Carlo Code ◽

X Rays ◽

Sky Survey

The eROSITA instrument on board the Russian Spectrum Roentgen Gamma spacecraft, which will be launched in 2013,will conduct an all sky survey in X-rays. A main objective of the survey is to observe galaxy clusters in order to constrain cosmological parameters and to obtain further knowledge about dark matter and dark energy. For the simulation of the eROSITA survey we present a Monte-Carlo code generating a mock catalogue of galaxy clusters distributed accordingto the mass function of [1]. The simulation generates the celestial coordinates as well as the cluster mass and redshift. From these parameters, the observed intensity and angular diameter are derived. These are used to scale Chandra cluster images as input for the survey-simulation.

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On the impact of baryons on the halo mass function, bias, and cluster cosmology

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa3473 ◽

2020 ◽

Vol 500 (2) ◽

pp. 2316-2335

Author(s):

Tiago Castro ◽

Stefano Borgani ◽

Klaus Dolag ◽

Valerio Marra ◽

Miguel Quartin ◽

...

Keyword(s):

Galaxy Clusters ◽

Cosmological Parameters ◽

High Sensitivity ◽

Mass Function ◽

Quality Data ◽

Systematic Uncertainties ◽

Statistical Precision ◽

Supernova Explosions ◽

Hydrodynamical Simulations ◽

The Impact

ABSTRACT Luminous matter produces very energetic events, such as active galactic nuclei and supernova explosions, that significantly affect the internal regions of galaxy clusters. Although the current uncertainty in the effect of baryonic physics on cluster statistics is subdominant as compared to other systematics, the picture is likely to change soon as the amount of high-quality data is growing fast, urging the community to keep theoretical systematic uncertainties below the ever-growing statistical precision. In this paper, we study the effect of baryons on galaxy clusters, and their impact on the cosmological applications of clusters, using the magneticum suite of cosmological hydrodynamical simulations. We show that the impact of baryons on the halo mass function can be recast in terms on a variation of the mass of the haloes simulated with pure N-body, when baryonic effects are included. The halo mass function and halo bias are only indirectly affected. Finally, we demonstrate that neglecting baryonic effects on haloes mass function and bias would significantly alter the inference of cosmological parameters from high-sensitivity next-generations surveys of galaxy clusters.

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Emergent Universe as an interaction in the dark sector

Modern Physics Letters A ◽

10.1142/s0217732317501528 ◽

2017 ◽

Vol 32 (28) ◽

pp. 1750152

Author(s):

Emiliano Marachlian ◽

I. E. Sánchez G. ◽

Osvaldo P. Santillán

Keyword(s):

Dark Matter ◽

Dark Energy ◽

Equation Of State ◽

Linear Equation ◽

Vacuum Energy ◽

Cosmological Parameters ◽

Emergent Universe ◽

Dark Sector ◽

Cosmological Scenario ◽

Friedmann Robertson Walker

A cosmological scenario where dark matter interacts with a variable vacuum energy for a spatially flat Friedmann–Robertson–Walker (FRW) spacetime is proposed and analyzed to show that with a linear equation of state and a particular interaction in the dark sector it is possible to get a model of an Emergent Universe. In addition, the viability of two particular models is studied by taking into account the recent observations. The updated observational Hubble data and the JLA supernovae data are used in order to constraint the cosmological parameters of the models and estimate the amount of dark energy in the radiation era. It is shown that the two models fulfil the severe bounds of [Formula: see text] at the 2[Formula: see text] level of Planck.

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Cosmological constraints from galaxy–lensing cross-correlations using BOSS galaxies with SDSS and CMB lensing

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz2922 ◽

2019 ◽

Vol 491 (1) ◽

pp. 51-68 ◽

Cited By ~ 3

Author(s):

Sukhdeep Singh ◽

Rachel Mandelbaum ◽

Uroš Seljak ◽

Sergio Rodríguez-Torres ◽

Anže Slosar

Keyword(s):

Cosmological Parameters ◽

Small Scale ◽

The Galaxy ◽

Scale Modelling ◽

Modelling Uncertainties ◽

Cent Level ◽

Cross Correlations ◽

Galaxy Bias ◽

The Impact ◽

Parameter Constraints

ABSTRACT We present cosmological parameter constraints based on a joint modelling of galaxy–lensing cross-correlations and galaxy clustering measurements in the SDSS, marginalizing over small-scale modelling uncertainties using mock galaxy catalogues, without explicit modelling of galaxy bias. We show that our modelling method is robust to the impact of different choices for how galaxies occupy dark matter haloes and to the impact of baryonic physics (at the $\sim 2{{\ \rm per\ cent}}$ level in cosmological parameters) and test for the impact of covariance on the likelihood analysis and of the survey window function on the theory computations. Applying our results to the measurements using galaxy samples from BOSS and lensing measurements using shear from SDSS galaxies and CMB lensing from Planck, with conservative scale cuts, we obtain $S_8\equiv \left(\frac{\sigma _8}{0.8228}\right)^{0.8}\left(\frac{\Omega _\mathrm{ m}}{0.307}\right)^{0.6}=0.85\pm 0.05$ (stat.) using LOWZ × SDSS galaxy lensing, and S8 = 0.91 ± 0.1 (stat.) using combination of LOWZ and CMASS × Planck CMB lensing. We estimate the systematic uncertainty in the galaxy–galaxy lensing measurements to be $\sim 6{{\ \rm per\ cent}}$ (dominated by photometric redshift uncertainties) and in the galaxy–CMB lensing measurements to be $\sim 3{{\ \rm per\ cent}}$, from small-scale modelling uncertainties including baryonic physics.

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The bivariate gas–stellar mass distributions and the mass functions of early- and late-type galaxies at

Publications of the Astronomical Society of Australia ◽

10.1017/pasa.2020.15 ◽

2020 ◽

Vol 37 ◽

Cited By ~ 3

Author(s):

Aldo Rodríguez-Puebla ◽

A. R. Calette ◽

Vladimir Avila-Reese ◽

Vicente Rodriguez-Gomez ◽

Marc Huertas-Company

Keyword(s):

Galaxy Formation ◽

Mass Function ◽

Stellar Mass ◽

Sloan Digital Sky Survey ◽

Random Errors ◽

Conditional Distributions ◽

Late Type ◽

Mass Distributions ◽

The Impact ◽

Mass Functions

Abstract We report the bivariate $\rm HI$ - and $\rm H_{2}$ -stellar mass distributions of local galaxies in addition of an inventory of galaxy mass functions, MFs, for $\rm HI$ , $\rm H_{2}$ , cold gas, and baryonic mass, separately into early- and late-type galaxies. The MFs are determined using the $\rm HI$ and $\rm H_{2}$ conditional distributions and the galaxy stellar mass function (GSMF). For the conditional distributions we use the results from the compilation presented in Calette et al. [(2018) RMxAA, 54, 443.]. For determining the GSMF from $M_{*}\sim3\times10^{7}$ to $3\times10^{12}\ \text{M}_{\odot}$ , we combine two spectroscopic samples from the Sloan Digital Sky Survey at the redshift range $0.0033<z<0.2$ . We find that the low-mass end slope of the GSMF, after correcting from surface brightness incompleteness, is $\alpha\approx-1.4$ , consistent with previous determinations. The obtained $\rm HI\,$ MFs agree with radio blind surveys. Similarly, the $\rm H_{2}\,$ MFs are consistent with CO follow-up optically-selected samples. We estimate the impact of systematics due to mass-to-light ratios and find that our MFs are robust against systematic errors. We deconvolve our MFs from random errors to obtain the intrinsic MFs. Using the MFs, we calculate cosmic density parameters of all the baryonic components. Baryons locked inside galaxies represent 5.4% of the universal baryon content, while $\sim\! 96\%$ of the $\rm HI$ and $\rm H_{2}$ mass inside galaxies reside in late-type morphologies. Our results imply cosmic depletion times of $\rm H_{2}$ and total neutral H in late-type galaxies of $\sim\!1.3$ and 7.2 Gyr, respectively, which shows that late type galaxies are on average inefficient in converting $\rm H_{2}$ into stars and in transforming $\rm HI$ gas into $\rm H_{2}$ . Our results provide a fully self-consistent empirical description of galaxy demographics in terms of the bivariate gas–stellar mass distribution and their projections, the MFs. This description is ideal to compare and/or to constrain galaxy formation models.

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Probing cosmic isotropy with a new X-ray galaxy cluster sample through the LX–T scaling relation

Astronomy and Astrophysics ◽

10.1051/0004-6361/201936602 ◽

2020 ◽

Vol 636 ◽

pp. A15 ◽

Cited By ~ 16

Author(s):

K. Migkas ◽

G. Schellenberger ◽

T. H. Reiprich ◽

F. Pacaud ◽

M. E. Ramos-Ceja ◽

...

Keyword(s):

Galaxy Clusters ◽

Statistical Significance ◽

Cosmological Parameters ◽

Galaxy Cluster ◽

Temperature Measurements ◽

Joint Analysis ◽

Scaling Relations ◽

Exact Nature ◽

X Rays ◽

X Ray

The isotropy of the late Universe and consequently of the X-ray galaxy cluster scaling relations is an assumption greatly used in astronomy. However, within the last decade, many studies have reported deviations from isotropy when using various cosmological probes; a definitive conclusion has yet to be made. New, effective and independent methods to robustly test the cosmic isotropy are of crucial importance. In this work, we use such a method. Specifically, we investigate the directional behavior of the X-ray luminosity-temperature (LX–T) relation of galaxy clusters. A tight correlation is known to exist between the luminosity and temperature of the X-ray-emitting intracluster medium of galaxy clusters. While the measured luminosity depends on the underlying cosmology through the luminosity distance DL, the temperature can be determined without any cosmological assumptions. By exploiting this property and the homogeneous sky coverage of X-ray galaxy cluster samples, one can effectively test the isotropy of cosmological parameters over the full extragalactic sky, which is perfectly mirrored in the behavior of the normalization A of the LX–T relation. To do so, we used 313 homogeneously selected X-ray galaxy clusters from the Meta-Catalogue of X-ray detected Clusters of galaxies. We thoroughly performed additional cleaning in the measured parameters and obtain core-excised temperature measurements for all of the 313 clusters. The behavior of the LX–T relation heavily depends on the direction of the sky, which is consistent with previous studies. Strong anisotropies are detected at a ≳4σ confidence level toward the Galactic coordinates (l, b) ∼ (280°, − 20°), which is roughly consistent with the results of other probes, such as Supernovae Ia. Several effects that could potentially explain these strong anisotropies were examined. Such effects are, for example, the X-ray absorption treatment, the effect of galaxy groups and low redshift clusters, core metallicities, and apparent correlations with other cluster properties, but none is able to explain the obtained results. Analyzing 105 bootstrap realizations confirms the large statistical significance of the anisotropic behavior of this sky region. Interestingly, the two cluster samples previously used in the literature for this test appear to have a similar behavior throughout the sky, while being fully independent of each other and of our sample. Combining all three samples results in 842 different galaxy clusters with luminosity and temperature measurements. Performing a joint analysis, the final anisotropy is further intensified (∼5σ), toward (l, b) ∼ (303°, − 27°), which is in very good agreement with other cosmological probes. The maximum variation of DL seems to be ∼16 ± 3% for different regions in the sky. This result demonstrates that X-ray studies that assume perfect isotropy in the properties of galaxy clusters and their scaling relations can produce strongly biased results whether the underlying reason is cosmological or related to X-rays. The identification of the exact nature of these anisotropies is therefore crucial for any statistical cluster physics or cosmology study.

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Analysis off(R)Theory Corresponding to NADE and NHDE

Advances in High Energy Physics ◽

10.1155/2013/790967 ◽

2013 ◽

Vol 2013 ◽

pp. 1-10 ◽

Cited By ~ 2

Author(s):

M. Sharif ◽

M. Zubair

Keyword(s):

Dark Energy ◽

Equation Of State ◽

Deceleration Parameter ◽

Holographic Dark Energy ◽

Cosmological Parameters ◽

State Parameter ◽

Future Evolution ◽

Energy Models ◽

Equation Of State Parameter ◽

Effective Description

We develop the connection off(R)theory with new agegraphic and holographic dark energy models. The functionf(R)is reconstructed regarding thef(R)theory as an effective description for these dark energy models. We show the future evolution offand conclude that these functions represent distinct pictures of cosmological eras. The cosmological parameters such as equation of state parameter, deceleration parameter, statefinder diagnostic, andw−w′analysis are investigated which assure the evolutionary paradigm off.

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The cosmological analysis of X-ray cluster surveys

Astronomy and Astrophysics ◽

10.1051/0004-6361/201731445 ◽

2018 ◽

Vol 614 ◽

pp. A72 ◽

Cited By ~ 1

Author(s):

A. Valotti ◽

M. Pierre ◽

A. Farahi ◽

A. Evrard ◽

L. Faccioli ◽

...

Keyword(s):

Cosmological Parameters ◽

Scaling Relations ◽

Temperature Relation ◽

Local Scaling ◽

X Ray ◽

Mass Size ◽

Final Error ◽

Hydrodynamical Simulations ◽

The Impact ◽

Size Relation

Context. This paper is the fourth of a series evaluating the ASpiX cosmological method, based on X-ray diagrams, which are constructed from simple cluster observable quantities, namely: count rate (CR), hardness ratio (HR), core radius (rc), and redshift. Aims. Following extensive tests on analytical toy catalogues (Paper III), we present the results of a more realistic study over a 711 deg2 template-based maps derived from a cosmological simulation. Methods. Dark matter haloes from the Aardvark simulation have been ascribed luminosities, temperatures, and core radii, using local scaling relations and assuming self-similar evolution. The predicted X-ray sky-maps were converted into XMM event lists, using a detailed instrumental simulator. The XXL pipeline runs on the resulting sky images, produces an observed cluster catalogue over which the tests have been performed. This allowed us to investigate the relative power of various combinations of the CR, HR, rc, and redshift information. Two fitting methods were used: a traditional Markov chain Monte Carlo (MCMC) approach and a simple minimisation procedure (Amoeba) whose mean uncertainties are a posteriori evaluated by means of synthetic catalogues. The results were analysed and compared to the predictions from the Fisher analysis (FA). Results. For this particular catalogue realisation, assuming that the scaling relations are perfectly known, the CR-HR combination gives σ8 and Ωm at the 10% level, while CR-HR-rc-z improves this to ≤3%. Adding a second HR improves the results from the CR-HR1-rc combination, but to a lesser extent than when adding the redshift information. When all coefficients of the mass-temperature relation (M-T, including scatter) are also fitted, the cosmological parameters are constrained to within 5–10% and larger for the M-T coefficients (up to a factor of two for the scatter). The errors returned by the MCMC, those by Amoeba and the FA predictions are in most cases in excellent agreement and always within a factor of two. We also study the impact of the scatter of the mass-size relation (M-Rc) on the number of detected clusters: for the cluster typical sizes usually assumed, the larger the scatter, the lower the number of detected objects. Conclusions. The present study confirms and extends the trends outlined in our previous analyses, namely the power of X-ray observable diagrams to successfully and easily fit at the same time, the cosmological parameters, cluster physics, and the survey selection, by involving all detected clusters. The accuracy levels quoted should not be considered as definitive. A number of simplifying hypotheses were made for the testing purpose, but this should affect any method in the same way. The next publication will consider in greater detail the impact of cluster shapes (selection and measurements) and of cluster physics on the final error budget by means of hydrodynamical simulations.

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THE EFFECT OF DIFFERENT OBSERVATIONAL DATA IN CONSTRAINING COSMOLOGICAL PARAMETERS

International Journal of Modern Physics Conference Series ◽

10.1142/s201019451200579x ◽

2012 ◽

Vol 10 ◽

pp. 85-94 ◽

Cited By ~ 5

Author(s):

YUNGUI GONG ◽

QING GAO ◽

ZONG-HONG ZHU

Keyword(s):

Dark Energy ◽

Equation Of State ◽

Observational Data ◽

Cosmological Parameters ◽

State Parameter ◽

Wilkinson Microwave Anisotropy Probe ◽

Model Parameters ◽

Type Ia Supernova ◽

Equation Of State Parameter ◽

Type Ia

We use the SNLS3 compilation of 472 type Ia supernova data, the baryon acoustic oscillation measurement of distance, and the cosmic microwave background radiation data from the seven year Wilkinson Microwave Anisotropy Probe to study the effect of their different combinations on the fittings of cosmological parameters. Neither BAO nor WMAP7 data alone gives good constraint on the equation of state parameter of dark energy, but both WMAP7 data and BAO data help type Ia supernova data break the degeneracies among the model parameters, hence tighten the constraint on the variation of equation of state parameter wa, and WMAP7 data does the job a little better. Although BAO and WMAP7 data provide reasonably good constraints on Ωm and Ωk, it is not able to constrain the dynamics of dark energy, we need SNe Ia data to probe the property of dark energy, especially the variation of the equation of state parameter of dark energy. For the SNLS SNe Ia data, the nuisance parameters α and β are consistent for all different combinations of the above data. Their impacts on the fittings of cosmological parameters are minimal. ΛCDM model is consistent with current observational data.

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Updated reduced CMB data and constraints on cosmological parameters

International Journal of Modern Physics D ◽

10.1142/s0218271815500716 ◽

2015 ◽

Vol 24 (10) ◽

pp. 1550071 ◽

Cited By ~ 3

Author(s):

Rong-Gen Cai ◽

Zong-Kuan Guo ◽

Bo Tang

Keyword(s):

Dark Energy ◽

Equation Of State ◽

Confidence Level ◽

Cosmological Parameters ◽

Hubble Constant ◽

Spatial Curvature ◽

Λcdm Model ◽

The One

We obtain the reduced CMB data {lA, R, z∗} from WMAP9, WMAP9+BKP, Planck+WP and Planck+WP+BKP for the ΛCDM and wCDM models with or without spatial curvature. We then use these reduced CMB data in combination with low-redshift observations to put constraints on cosmological parameters. We find that including BKP results in a higher value of the Hubble constant especially when the equation of state (EOS) of dark energy and curvature are allowed to vary. For the ΛCDM model with curvature, the estimate of the Hubble constant with Planck+WP+Lensing is inconsistent with the one derived from Planck+WP+BKP at about 1.2σ confidence level (CL).

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