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Joint constraints on cosmological parameters using future multi-band gravitational wave standard siren observations

Chinese Physics C 2023年第6期47卷 188-198页

作者：金上捷邢双双邵悦张敬飞张鑫 Key Laboratory of Cosmology and Astrophysics(Liaoning Province)&Department of Physics College of SciencesNortheastern UniversityShenyang 110819China Key Laboratory of Data Analytics and Optimization for Smart Industry(Ministry of Education) Northeastern UniversityShenyang 110819China National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern UniversityShenyang 110819China

Gravitational waves(GWs)from compact binary coalescences can be used as standard sirens to explore the cosmic expansion *** the next decades,it is anticipated that we could obtain the multi-band GW standard siren data(from nanohertz to a few hundred hertz),which are expected to play an important role in cosmological parameter *** this work,we provide,for the first time to the best of our knowledge,joint constraints on cosmological parameters using the future multi-band GW standard siren *** simulate the multi-band GW standard sirens based on the SKA-era pulsar timing array(PTA),Taiji observatory,and Cosmic Explorer(CE)to perform cosmological *** theΛCDM model,we find that the joint PTA+Taiji+CE data could provide a tight constraint on the Hubble constant with a 0.5%***,PTA+Taiji+CE could break the cosmological parameter degeneracies generated by CMB,especially in the dynamical dark energy *** combining the PTA+Taiji+CE data with the CMB data,the constraint precisions of?_(m)and H_(0)are 1.0%and 0.3%,respectively,meeting the standard of precision *** joint CMB+PTA+Taiji+CE data giveσ(_(w))=0.028 in the wCDM model andσ(w_(0))=0.11 andσ(w_(a))=0.32 in the w_(0)w_(a)CDM model,which are comparable with or close to the latest constraint results by CMB+BAO+*** conclusion,the future multi-band GW observations are expected to be used for exploring the nature of dark energy and measuring the Hubble constant.

关键词： gravitational wave standard siren multi-band observations cosmological parameters dark energy

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The Evolving Absolute Magnitude of Type 1a Supernovae and Its Critical Impact on the cosmological parameters

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International Journal of Astronomy and Astrophysics 2023年第2期13卷 39-60页

作者： Abraham P. Mahtessian Garen S. Karapetian Martik A. Hovhannisyan Lazar A. Mahtessian Byurakan Astrophysical Observatory after V. Ambartsumian NAS of the Republic of Armenia Byurakan Republic of Armenia Institute of Applied Problems of Physics NAS of the Republic of Armenia 25 Hrachya Nersissian Str. Yerevan Republic of Armenia

In this work, a computer optimization model has been developed that allows one to load the initial data of observations of supernovae 1a into a table and, in simple steps, by searching for the best fit between observations and theory, obtain the values of the parameters of cosmological models. The optimization is carried out assuming that the absolute magnitude of supernovae is not constant, but evolves with time. It is assumed that the dependence of the absolute magnitude on the redshift is linear: M = M( z = 0) + εc z, where εc is the evolution coefficient of the absolute magnitude of type 1a supernovae. In the case of a flat universe ( ΩM + ΩΛ = 1 ), the best fit between theory and observation is εc = 0.304. In this case, for the cosmological parameters we obtain ΩΛ = 0.000, ΩM =1.000. Naturally, this result exactly coincides with the simulation result for the model with zero cosmological constant ( εc = 0.304, q0 = 0.500 ). Within the framework of the ΛCDM model, without restriction on space curvature ( ΩM + ΩΛ+ ΩK = 1 ), we obtain the following values: εc = 0.304, ΩΛ = 0.000, ΩM = 1.000, ΩK =0.000. Those, this case also leads to a flat model of the Universe ( ΩK =0.000 ). In this work, the critical influence of the absolute magnitude M of type 1a supernovae on the cosmological parameters is also shown. In particular, it was found that a change in this value by only 0.4m (from -19.11 to -18.71) leads to a change in the parameters from ΩΛ = 0.7 and ΩM = 0.3 to ΩΛ = 0 and ΩM =1.

关键词： Supernovae SNe1a cosmological parameters Cosmology Acceleration

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Quasi-2D weak lensing cosmological constraints using the PDF-SYM method

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 44-58页

作者： Zhenjie Liu Jun Zhang Hekun Li Zhi Shen Cong Liu Department of Astronomy Shanghai Jiao Tong UniversityShanghai 200240China Shanghai Key Laboratory for Particle Physics and Cosmology Shanghai 200240China Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China

Cosmic shear statistics,such as the two-point correlation function(2PCF),can be evaluated with the PDF-SYM method instead of the traditional weighted-sum *** makes use of the full PDF information of the shear estimators,and does not require weightings on the shear estimators,which can in principle introduce additional systematic *** work presents our constraints on S8and?mfrom the shear-shear correlations using the PDF-SYM *** data we use is from the z-band images of the Dark Energy Camera Legacy Survey(DECa LS),which covers about 10000 deg2with more than 100 million *** shear catalog is produced by the Fourier Quad method,and well tested on the real data itself with the field-distortion *** main approach is called quasi-2D as we do use the photo-z information of each individual galaxy,but without dividing the galaxies into redshift *** mainly use galaxy pairs within the redshift interval between 0.2 and 1.3,and the angular range from 4.7 to 180 *** analysis yields S8=0.762±0.026 and?m=0.234±0.075,with the baryon effects and the intrinsic alignments *** results are robust against redshift *** check the consistency of our results by deriving the cosmological constraints from auto-correlations ofγ1andγ2separately,and find that they are consistent with each other,but the constraints from theγ1component are much weaker than that fromγ*** implies a much worse data quality ofγ1,which is likely due to additional shear uncertainties caused by CCD electronics(according to the survey strategy of DECa LS).We also perform a pure 2D analysis,which gives S8=0.81_(-0.04)^(+0.03)and?m=0.25_(-0.05)^(+0.06).Our findings demonstrate the potential of the PDF-SYM method for precision cosmology.

关键词： weak lensing shear-shear correlations cosmological parameters observations analysis

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Improving constraint onΩ_(m)from SDSS using marked correlation functions

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 207-224页

作者： Limin Lai Jiacheng Ding Xiaolin Luo Yizhao Yang Zihan Wang Keshi Liu Guanfu Liu Xin Wang Yi Zheng Zhaoyu Li Le Zhang Xiao-Dong Li School of Physics and Astronomy Sun Yat-sen University Zhuhai CampusZhuhai 519082China Department of Astronomy Shanghai Jiao Tong UniversityShanghai 200240China Department of Astronomy Tsinghua UniversityBeijing 100084China CSST Science Center for the Guangdong-Hong Kong-Macao Greater Bay Area SYSUZhuhai 519082China Peng Cheng Laboratory Shenzhen 518000China

Large-scale structure(LSS)surveys will increasingly provide stringent constraints on our cosmological ***,the density-marked correlation function(MCF)has been introduced,offering an easily computable density-correlation *** have demonstrated that MCFs offer additional,independent constraints on cosmological models beyond the standard two-point correlation(2PCF).In this study,we apply MCFs for the first time to SDSS CMASS data,aiming to investigate the statistical information regarding clustering and anisotropy properties in the Universe and assess the performance of various weighting schemes in MCFs,and finally obtain constraints onΩ_(m).Upon analyzing the CMASS data,we observe that,by combining different weights(α=[-0.2,0,0.2,0.6]),the MCFs provide a tight and independent constraint on the cosmological parameterΩ_(m),yieldingΩ_(m)=0.293±0.006 at the 1σlevel,which represents a significant reduction in the statistical error by a factor of 3.4 compared to that from *** constraint is consistent with recent findings from the small-scale clustering of BOSS galaxies(Zhai et ***.J.948,99(2023))within the 1σ***,we also find that our estimate is lower than the Planck measurements by about 2.6σ,indicating the potential presence of new physics beyond the standard cosmological model if all the systematics are fully *** method outlined in this study can be extended to other surveys and datasets,allowing for the constraint of other cosmological ***,it serves as a valuable tool for forthcoming emulator analysis on the Chinese Space Station Telescope(CSST).

关键词： large scale structure of universe dark energy cosmological parameters marked weighted correlation function

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Possible bias of the constraints on the Hubble constant owing to the quasi-Gaussian distribution of DM_(IGM)in fast radio bursts

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Chinese Physics C 2024年第7期48卷 211-220页

作者：陈贵垚李昕 Department of Physics Chongqing UniversityChongqing 401331China Chongqing Key Laboratory for Strongly Coupled Physics Chongqing UniversityChongqing 401331China

Fast radio bursts(FRBs)are useful cosmological probes with numerous applications in *** distribution of the dispersion measurement contribution from the intergalactic medium is a key issue.A quasi-Gaussian distribution has been used to replace the traditional Gaussian distribution,yielding promising ***,this study suggests that there may be additional challenges in its *** used 35 well-localized FRBs to constrain the Hubble constant H_(0)along with two FRB-related parameters,yielding H_(0)=■The best-fitting Hubble constant H_(0)is smaller than the value obtained from the Cosmic Microwave Background(CMB),which may be caused by the small sample size of current FRB *** Carlo simulations indicate that a set of 100 simulated FRBs provides a more precise fitting result for the Hubble ***,the precision of the Hubble constant does not improve when further enlarging the FRB *** simulations reveal a systematic deviation in the fitting results of H_(0),attributed to the quasi-Gaussian distribution of the dispersion measure in the intergalactic *** this,the results remain reliable within 1σuncertainty,assuming that a sufficient number of FRB data points are available.

关键词： fast radio bursts Hubble constant cosmological parameters

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cosmological parameter estimation from large-scale structure deep learning

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Science China(Physics,Mechanics & Astronomy) 2020年第11期63卷 36-50页

作者： ShuYang Pan MiaoXin Liu Jaime Forero-Romero Cristiano G.Sabiu ZhiGang Li HaiTao Miao Xiao-Dong Li School of Physics and Astronomy Sun Yat-Sen UniversityGuangzhou 510297China Departamento de Física Universidad de los AndesBogotáCP 111711Colombia Department of Astronomy Yonsei UniversitySeoul 03722Korea College of Physics and Electronic Engineering Nanyang Normal UniversityNanyang 473061China

We propose a light-weight deep convolutional neural network(CNN)to estimate the cosmological parameters from simulated 3-dimensional dark matter distributions with high *** training set is based on 465 realizations of a cubic box with a side length of 256 h-1 Mpc,sampled with 1283 particles interpolated over a cubic grid of 1283 *** volumes have cosmological parameters varying within the flatΛCDM parameter space of 0.16≤?m≤0.46 and 2.0≤109 As≤*** neural network takes as an input cubes with 32^3 oxels and has three convolution layers,three dense layers,together with some batch normalization and pooling *** the final predictions from the network we find a 2.5%bias on the primordial amplitudeσ8 that cannot easily be resolved by continued *** correct this bias to obtain unprecedented accuracy in the cosmological parameter estimation with statistical uncertainties ofδ?m=0.0015 andδσ8=0.0029,which are several times better than the results of previous CNN *** with a 2-point analysis method using the clustering region of 0-130 and 10-130 h-1 Mpc,the CNN constraints are several times and an order of magnitude more precise,***,we conduct preliminary checks of the error-tolerance abilities of the neural network,and find that it exhibits robustness against smoothing,masking,random noise,global variation,rotation,reflection,and simulation *** effects are well understood in typical clustering analysis,but had not been tested before for the CNN *** work shows that CNN can be more promising than people expected in deriving tight cosmological constraints from the cosmic large scale structure.

关键词： large-scale structure of Universe cosmological parameters dark energy machine learning

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Observational Constraints on the Unified Dark-Energy-Dark-Matter Model

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Chinese Physics Letters 2007年第3期24卷 843-845页

作者：吴普训余洪伟 School of Sciences and Institute of Physics Central South University of Forestry and Technology Changsha 410004 Department of Physics and Institute of Physics Normal University Changsha 410081

We investigate the constraints on a generalized Chaplygin gas （GCG） model using the gold sample type-Ia supernovae （She Ia） data, the new Supernova Legacy Survey （SNLS） Sne Ia data and the size of baryonic acoustic oscillation peak found in Sloan Digital Sky Survey （SDSS）. In a spatially flat universe case we obtain, at a 95.4% confidence level, A8 = 0.76^＋0.07 -0.07 and α= 0.028^＋0.322 -0.2382 Our results are consistent with the ACDM model （α= 0）, but rule out the standard Chaplygin gas model （α= 1）.

关键词： GENERALIZED CHAPLYGIN-GAS HIGH-REDSHIFT SUPERNOVAE HUBBLE-SPACE-TELESCOPE cosmological parameters CONSTANT OMEGA(LAMBDA) STATISTICS MAXIMA-1 OMEGA(M) UNIVERSE

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Revisiting progenitor-age dependence of type Ia supernova luminosity standardization process

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Science China(Physics,Mechanics & Astronomy) 2023年第12期66卷 176-183页

作者： Junchao Wang Zhiqi Huang Lu Huang School of Physics and Astronomy Sun Yat-sen UniversityZhuhai 519082China CSST Science Center for the Guangdong-Hongkong-Macao Greater Bay Area Sun Yat-sen UniversityZhuhai 519082China

Much of the research in supernova cosmology is based on an assumption that the peak luminosity of type Ia supernovae(SNe Ia),after a standardization process,is independent of the galactic environment.A series of recent studies suggested that there is a significant correlation between the standardized luminosity and the progenitor age of SNe *** correlation found in the most recent work by Lee et al.[***.517,2697(2022)]is strong enough to explain the extra dimming of distant SNe Ia and therefore casts doubts on the direct evidence of cosmic *** present work incorporates the uncertainties of progenitor ages,which were ignored in Lee et al.,into a fully Bayesian inference *** find a weaker dependence of supernova standardized luminosity on the progenitor age,but the detection of correlation remains significant(3.5σ).Assuming that such correlation can be extended to high redshift and applying it to the Pantheon SN Ia data set,we confirm that when the Hubble residual does not include intrinsic scatter,the age-bias could be the primary cause of the observed extra dimming of distant SNe ***,we use the PAge formalism,which is a good approximation to many dark energy and modified gravity models,to do a model *** find that if intrinsic scatter is included in the Hubble residual,the Lambda cold dark matter model remains a good ***,in a scenario without intrinsic scatter,the Lambda cold dark matter model faces a challenge.

关键词： distance scale cosmological parameters dark energy

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cosmological application on five-dimensional teleparallel theory equivalent to general relativity

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Chinese Physics B 2012年第10期21卷 122-129页

作者： Gamal G.L.Nashed Mathematics Department Faculty of ScienceKing Faisal UniversityP.O.Box 380 Al-Ahsaa 31982the Kingdom of Saudi Arabia Mathematics Department Faculty of ScienceAin Shams UniversityCairo 11566Egypt Center for Theoretical Physics British University of EgyptSherouk City 11837P.O.Box 43Egypt

A theory of（4＋1）-dimensional gravity has been developed on the basis of which equivalent to the theory of general relativity by *** fundamental gravitational field variables are the 5-dimensional（5D） vector fields（pentad）,defined globally on a manifold M,and gravity is attributed to the *** Lagrangian density is quadratic in the torsion *** then apply the field equations to two different homogenous and isotropic geometric structures which give the same line element,i.e.,FRW in five *** cosmological parameters are calculated and some cosmological problems are discussed.

关键词： 5D teleparallel equivalent of general relativity 5D solutions cosmological parameters cosmological problems

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cosmological implications of different baryon acoustic oscillation data

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Science China(Physics,Mechanics & Astronomy) 2017年第4期60卷 10-22页

作者： Shuang Wang YaZhou Hu Miao Li School of Physics and Astronomy Sun Yat-Sen UniversityZhuhai 519082China Kavli Institute of Theoretical Physics China Chinese Academy of SciensesBeijing 100190China

In this work, we explore the cosmological implications of different baryon acoustic oscillation （BAO） data, including the BAO data extracted by using the spherically averaged one-dimensional galaxy clustering （GC） statistics （hereafter BAO 1） and the BAO data obtained by using the anisotropic two-dimensional GC statistics （hereafter BAO2）. To make a comparison, we also take into account the case without BAO data （hereafter NO BAO）. Firstly, making use of these BAO data, as well as the SNLS3 type la supernovae sample and the Planck distance priors data, we give the cosmological constraints of the ACDM, the wCDM, and the Chevallier-Polarski-Linder （CPL） model. Then, we discuss the impacts of different BAO data on cosmological consquences, including its effects on parameter space, equation of state （EoS）, figure of merit （FoM）, deceleration-acceleration transition redshift, Hubble parameter H（z）, deceleration parameter q（z）, statefinder hierarchy S3^（1）（z）, S4^（1）（z） and cosmic age t（z）. We find that：（1） NO BAO data always give a smallest fractional matter density Ωm0, a largest fractional curvature density Ωk0 and a largest Hubble constant h; in contrast, BAO1 data always give a largest Ωm0, a smallest Ωk0 and a smallest h. （2） For the wCDM and the CPL model, NO BAO data always give a largest EoS w; in contrast, BA02 data always give a smallest w. （3） Compared with the case of BAO1, BAO2 data always give a slightly larger FoM, and thus can give a cosmological constraint with a slightly better accuracy. （4） The impacts of different BAO data on the cosmic evolution and the comic age are very small, and cannot be distinguished by using various dark energy diagnoses and the cosmic age data.

关键词： cosmology dark energy observations cosmological parameters

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