Masahiro Takada

Nonlinear power spectrum in the presence of massive neutrinos: perturbation theory approach, galaxy bias and parameter forecasts (2009)

Saito, Shun, Takada, Masahiro, Taruya, Atsushi

Future or ongoing galaxy redshift surveys can put stringent constraints on neutrinos masses via the high-precision measurements of galaxy power spectrum, when combined with cosmic microwave...

Tests of Gravity from Imaging and Spectroscopic Surveys (2009)

Guzik, Jacek, Jain, Bhuvnesh, Takada, Masahiro

Tests of gravity on large-scales in the universe can be made using both imaging and spectroscopic surveys. The former allow for measurements of weak lensing, galaxy clustering and cross-correlations...

Simulations of Wide-Field Weak Lensing Surveys I: Basic Statistics and Non-Gaussian Effects (2009)

Sato, Masanori, Hamana, Takashi, Takahashi, Ryuichi, Takada, Masahiro, Yoshida, Naoki, Matsubara, Takahiko, ...

We study the lensing convergence power spectrum and its covariance for a standard LCDM cosmology. We run 400 cosmological N-body simulations and use the outputs to perform a total of 1000 independent...

LoCuSS: Subaru Weak Lensing Study of 30 Galaxy Clusters (2009)

Okabe, Nobuhiro, Takada, Masahiro, Umetsu, Keiichi, Futamase, Toshifumi, Smith, Graham P.

(Abridged) We use Subaru data to conduct a detailed weak-lensing study of the dark matter distribution in a sample of 30 X-ray luminous galaxy clusters at 0.15

Simulations of Baryon Acoustic Oscillations II: Covariance matrix of the matter power spectrum (2009)

Takahashi, Ryuichi, Yoshida, Naoki, Takada, Masahiro, Matsubara, Takahiko, Sugiyama, Naoshi, Kayo, Issha, ...

We use 5000 cosmological N-body simulations of 1(Gpc/h)^3 box for the concordance LCDM model in order to study the sampling variances of nonlinear matter power spectrum. We show that the non-Gaussian...

Constraints on Neutrino Masses from Weak Lensing (2008)

Ichiki, Kiyotomo, Takada, Masahiro, Takahashi, Tomo

The weak lensing (WL) distortions of distant galaxy images are sensitive to neutrino masses by probing the suppression effect on clustering strengths of total matter in large-scale structure. We use...

The Impact of Non-Gaussian Errors on Weak Lensing Surveys (2008)

Takada, Masahiro, Jain, Bhuvnesh

The weak lensing power spectrum carries cosmological information via its dependence on the growth of structure and on geometric factors. Since much of the cosmological information comes from scales...

Impact of massive neutrinos on nonlinear matter power spectrum (2008)

Saito, Shun, Takada, Masahiro, Taruya, Atsushi

We present the first attempt to analytically study the nonlinear matter power spectrum for a mixed dark matter (cold dark matter plus neutrinos of total mass ~0.1eV) model based on cosmological...

Probing dark energy with cluster counts and cosmic shear power spectra: including the full covariance (2007)

Takada, Masahiro, Bridle, Sarah

(Abridged) Combining cosmic shear power spectra and cluster counts is powerful to improve cosmological parameter constraints and/or test inherent systematics. However they probe the same cosmic mass...

Probing the Cluster Mass Distribution using Subaru Weak Lensing Data (2007)

Umetsu, Keiichi, Takada, Masahiro, Broadhurst, Tom

We present results from a weak lensing analysis of the galaxy cluster A1689 (z=0.183) based on deep wide-field imaging data taken with Suprime-Cam on Subaru telescope. A maximum entropy method has...

Color Tomography (2006)

Jain, Bhuvnesh, Connolly, Andrew, Takada, Masahiro

Lensing tomography with multi-color imaging surveys can probe dark energy and the cosmological power spectrum. However accurate photometric redshifts for tomography out to high redshift require...

Can a galaxy redshift survey measure dark energy clustering? (2006)

Takada, Masahiro

(abridged) A wide-field galaxy redshift survey allows one to probe galaxy clustering at largest spatial scales, which carries an invaluable information on horizon-scale physics complementarily to the...

Cosmology with High-redshift Galaxy Survey: Neutrino Mass and Inflation (2005)

Takada, Masahiro, Komatsu, Eiichiro, Futamase, Toshifumi

(abridged) High-z galaxy redshift surveys open up exciting possibilities for precision determinations of neutrino masses and inflationary models. The high-z surveys are more useful for cosmology than...

Systematic Errors in Future Weak Lensing Surveys: Requirements and Prospects for Self-Calibration (2005)

Huterer, Dragan, Takada, Masahiro, Bernstein, Gary, Jain, Bhuvnesh

We study the impact of systematic errors on planned weak lensing surveys and compute the requirements on their contributions so that they are not a dominant source of the cosmological parameter error...

Can the Steep Mass Profile of A1689 Be Explained by a Triaxial Dark Halo? (2005)

Oguri, Masamune, Takada, Masahiro, Umetsu, Keiichi, Broadhurst, Tom

The steep mass profile of A1689 derived from recent detailed lensing observations is not readily reconciled with the low concentration halos predicted by the standard CDM model. However, halo...

The Surprisingly Steep Mass Profile of Abell 1689, from a Lensing Analysis of Subaru Images (2004)

Broadhurst, Tom, Takada, Masahiro, Umetsu, Keiichi, Kong, Xu, Arimoto, Nobuo, Chiba, Masashi, ...

Subaru observations of A1689 (z=0.183) are used to derive an accurate, model-independent mass profile for the entire cluster, r

Calibrating the Nonlinear Matter Power Spectrum: Requirements for Future Weak Lensing Surveys (2004)

Huterer, Dragan, Takada, Masahiro

Uncertainties in predicting the nonlinear clustering of matter are among the most serious theoretical systematics facing the upcoming wide-field weak gravitational lensing surveys. We estimate the...

Baryon Oscillations and Dark-Energy Constraints from Imaging Surveys (2004)

Dolney, Derek, Jain, Bhuvnesh, Takada, Masahiro

Baryonic oscillations in the galaxy power spectrum have been studied as a way of probing dark-energy models. While most studies have focused on spectroscopic surveys at high redshift, large...

Effects of halo substructure on the power spectrum and bispectrum (2004)

Dolney, Derek, Jain, Bhuvnesh, Takada, Masahiro

We study the effects of halo substructure and a distribution in the concentration parameter of haloes on large-scale structure statistics. The effects on the power spectrum and bispectrum are studied...

Tomography of lensing cross power spectra (2003)

Takada, Masahiro, White, Martin

By obtaining photometric redshift information, tomography allows us to cross-correlate galaxy ellipticities in different source redshift bins. The cross-correlation is non-vanishing because the...

Searching for massive clusters in weak lensing surveys (2003)

Hamana, Takashi, Takada, Masahiro, Yoshida, Naoki

We explore the ability of weak lensing surveys to locate massive clusters. We use both analytic models of dark matter halos and mock weak lensing surveys generated from a large cosmological N-body...

Cosmological parameters from lensing power spectrum and bispectrum tomography (2003)

Takada, Masahiro, Jain, Bhuvnesh

We examine how lensing tomography with the bispectrum and power spectrum can constrain cosmological parameters and the equation of state of dark energy. Our analysis uses the full information at the...

Three-Point Correlations in Weak Lensing Surveys: Model Predictions and Applications (2003)

Takada, Masahiro, Jain, Bhuvnesh

We use the halo model of clustering to compute two- and three-point correlation functions for weak lensing, and apply them in a new statistical technique to measure properties of massive halos. We...

The Three-Point Correlation Function for Spin-2 Fields (2002)

Takada, Masahiro, Jain, Bhuvnesh

The three-point correlation function (3PCF) of the spin-2 fields, the cosmic shear and cosmic microwave background polarization fields, is a statistical measure of non-Gaussian signals. At each...

The Three-Point Correlation Function in Cosmology (2002)

Takada, Masahiro, Jain, Bhuvnesh

With the advent of high-quality surveys in cosmology the full three-point correlation function will be a valuable statistic for describing structure formation models. It contains information on...

Probing Intracluster Magnetic Fields with Cosmic Microwave Background Polarization (2002)

Ohno, Hiroshi, Takada, Masahiro, Dolag, Klaus, Bartelmann, Matthias, Sugiyama, Naoshi

Intracluster magnetic fields with $ \sim \mu G $ strength induce Faraday rotation on the cosmic microwave background (CMB) polarization. Measurements of this effect can potentially probe the detailed...

The Kurtosis of the Cosmic Shear Field (2002)

Takada, Masahiro, Jain, Bhuvnesh

We study the fourth-order moment of the cosmic shear field using the dark matter halo approach to describe the nonlinear gravitational evolution of structure in the universe. Since the third-order...

Faraday Rotation Effect of Intracluster Magnetic Field on Cosmic Microwave Background Polarization (2001)

Takada, Masahiro, Ohno, Hiroshi, Sugiyama, Naoshi

The observed magnetic field of microgauss strength in clusters of galaxies should induce the Faraday rotation effect on the linearly polarized cosmic microwave background (CMB) radiation when the CMB...

On the Cross-Correlation between Dark Matter Distribution and Secondary CMB Anisotropies by Ionized Intergalactic Medium (2001)

Takada, Masahiro, Sugiyama, Naoshi

We investigate a cross-correlation between the weak gravitational lensing field of the large-scale structure, $\kappa$, and the secondary temperature fluctuation field, $\Delta$, of cosmic microwave...

Implication of Omega_m through the Morphological Analysis of Weak Lensing Fields (2001)

Sato, Jun'ichi, Takada, Masahiro, Jing, Y. P., Futamase, Toshifumi

We apply the morphological descriptions of two-dimensional contour map, the so-called Minkowski functionals (the area fraction, circumference, and Euler characteristics), to the convergence field...

Lensing-induced Non-Gaussian Signatures in the Cosmic Microwave Background (2001)

Takada, Masahiro

We propose a new method for extracting the non-Gaussian signatures on the isotemperature statistics in the cosmic microwave background (CMB) sky, which is induced by the gravitational lensing due to...

Number Count of Peaks in the CMB Map (2000)

Futamase, Toshifumi, Takada, Masahiro

We investigate the dependence of cosmological parameters on the number count of peaks (local maxima and minima) in the cosmic microwave background (CMB) sky. The peak statistics contains the whole...

Effects of weak lensing on the topology of CMB maps (2000)

Schmalzing, Jens, Takada, Masahiro, Futamase, Toshifumi

We investigate the non-Gaussian signatures in Cosmic Microwave Background (CMB) maps induced by the intervening large-scale structure through weak lensing. In order to measure the deviation from the...

Detectability of Gravitational Lensing Effect on the Two-point Correlation Function of Hotspots in the CMB maps (2000)

Takada, Masahiro, Futamase, Toshifumi

We present quantitative investigations of the weak lensing effect on the two-point correlation functions of local maxima (hotspots), $\xipk(\theta)$, in the cosmic microwave background (CMB) maps....

Gravitational Lensing Effect on the Two-Point Correlation of Hot Spots in the Cosmic Microwave Background (2000)

Masahiro Takada, Eiichiro Komatsu, Toshifumi Futamase

We investigate the weak gravitational lensing effect that is due to the large-scale structure of the universe on two-point correlations of local maxima (hot spots) in the two-dimensional sky map of...

Gravitational Lensing Effect on the Two-point Correlation of Hotspots in the Cosmic Microwave Background (1999)

Takada, Masahiro, Komatsu, Eiichiro, Futamase, Toshifumi

We investigate the weak gravitational lensing effect due to the large-scale structure of the universe on two-point correlations of local maxima ({\em hotspots}) in the 2D sky map of the cosmic...

How is the local-scale gravitational instability influenced by the surrounding large-scale structure formation? (1999)

Takada, Masahiro, Futamase, Toshifumi

We develop the formalism to investigate the relation between the evolution of the large-scale (quasi) linear structure and that of the small-scale nonlinear structure in Newtonian cosmology within...

On a Growing Transverse Mode as a Post-Newtonian Effect in the Large-Scale Structure Formation (1998)

Takada, Masahiro, Futamase, Toshifumi

We point out the existence of a new type of growing transverse mode in the gravitational instability. This appears as a post-Newtonian effect to Newtonian dynamics. We demonstrate this existence by...

Post-Newtonian Lagrangian Perturbation Approach to the Large-Scale Structure Formation (1997)

Takada, Masahiro, Futamase, Toshifumi

We formulate the Lagrangian perturbation theory to solve the non-linear dynamics of self-gravitating fluid within the framework of the post-Newtonian approximation in general relativity, using the...