New Optimised Estimators for the Primordial Trispectrum (2009)
Munshi, Dipak, Heavens, Alan, Cooray, Asantha, Smidt, Joseph, Coles, Peter, Serra, Paolo
Cosmic microwave background studies of non-Gaussianity involving higher-order multispectra can distinguish between early universe theories that predict nearly identical power spectra. However, the...
Calabrese, Erminia, Smidt, Joseph, Amblard, Alexandre, Cooray, Asantha, Melchiorri, Alessandro, Serra, Paolo, ...
We measure the skewness power spectrum of the Cosmic Microwave Background (CMB) anisotropies optimized for a detection of the secondary bispectrum generated by the correlation of the CMB lensing...
Secondary non-Gaussianity and Cross-Correlation Analysis (2009)
Munshi, Dipak, Valageas, Patrick, Cooray, Asantha, Heavens, Alan
We develop optimised estimators of two sorts of power spectra for fields defined on the sky, in the presence of partial sky coverage. The first is the cross-power spectrum of two fields on the sky;...
Adiabatic versus Isocurvature Non--Gaussianity (2009)
Hikage, Chiaki, Munshi, Dipak, Heavens, Alan, Coles, Peter
We study the extent to which one can distinguish primordial non--Gaussianity (NG) arising from adiabatic and isocurvature perturbations. We make a joint analysis of different NG models based on...
A New Approach to Probing Primordial Non-Gaussianity (2009)
We address the dual challenge of estimating deviations from Gaussianity arising in models of the Early Universe, whilst retaining information necessary to assess whether a detection of...
Bias and Hierarchical Clustering (2007)
Peter Coles Adrian, Dipak Munshi
It is now well established that galaxies are biased tracers of the distribution of matter, although it is still not known what form this bias takes. In local bias models the propensity for a galaxy...
Weak Lensing from Strong Clustering (2007)
Dipak Munshi And, Dipak Munshi, Peter Coles
We investigate the effect of weak gravitational lensing in the limit of small angular scales where projected galaxy clustering is strongly nonlinear. This is the regime likely to be probed by future...
Large Scale Structure In The Universe: Theory Vs Observations (2007)
I discuss main observational inputs and analytical methods in formation of large scale structure in the universe with particular reference to approximate methods for understanding gravitational...
How many SNeIa do we need to detect the effect of weak lensing ? (2006)
Munshi, Dipak, Valageas, Patrick
We show that as many as 4000 SNeIa may be required to detect the effect of weak lensing on their flux distribution with a high level of significance. However, if the intrinsic SNeIa magnitude...
Munshi, Dipak, Valageas, Patrick
We study the possibility of using the entire probability distribution function (PDF) of the aperture mass Map and its related cumulative probability distribution function (CPDF) to obtain meaningful...
Principal Component Analysis of Weak Lensing Surveys (2005)
Munshi, Dipak, Kilbinger, Martin
We study degeneracies between cosmological parameters and measurement errors from cosmic shear surveys using a principal component analysis of the Fisher matrix. We simulate realistic survey...
Cosmological Constraints from Weak Lensing Surveys (2005)
Munshi, Dipak, Valageas, Patrick
Focusing on the well motivated aperture mass statistics $\Map$, we study the possibility of constraining cosmological parameters using future space based SNAP class weak lensing missions. Using...
Designing Weak Lensing Surveys: A Generalised Eigenmode Analysis (2005)
Kilbinger, Martin, Munshi, Dipak
We study the estimators of various second-order weak lensing statistics such as the shear correlation functions xi_\pm and the aperture mass dispersion which can directly be constructed from weak...
Cosmology with Weak Lensing Surveys (2005)
Munshi, Dipak, Valageas, Patrick
Weak gravitational lensing surveys measure the distortion of the image of distant sources due to the deflections of light rays by the fluctuations of the gravitational potential along the line of...
Covariance of Weak Lensing Observables (2004)
Munshi, Dipak, Valageas, Patrick
Analytical expressions for covariances of weak lensing statistics related to the aperture mass $\Map$ are derived for realistic survey geometries such as SNAP for a range of smoothing angles and...
On Cross-correlating Weak Lensing Surveys (2004)
Munshi, Dipak, Valageas, Patrick
The present generation of weak lensing surveys will be superseded by surveys run from space with much better sky coverage and high level of signal to noise ratio, such as SNAP. However, removal of...
Evolution of the Cosmological Density Distribution Function: A New Analytical Model (2004)
Valageas, Patrick, Munshi, Dipak
The one-point probability distribution function (pdf) of the large-scale density field is an important tool to follow the evolution of cosmological structures. In this paper we present a new model...
On the estimation of gravity-induced non-Gaussianities from weak lensing surveys (2004)
Valageas, Patrick, Munshi, Dipak, Barber, Andrew J.
We study various measures of weak lensing distortions in future surveys, taking into account the noise arising from the finite survey size and the intrinsic ellipticity of galaxies. We also consider...
Weak lensing shear and aperture-mass from linear to non-linear scales (2003)
Munshi, Dipak, Valageas, Patrick, Barber, Andrew J.
In this paper we describe the predictions for the smoothed weak lensing shear and aperture-mass of two simple analytical models of the density field: the minimal tree-model and the stellar model....
Barber, Andrew J., Munshi, Dipak, Valageas, Patrick
Weak lensing convergence can be used directly to map and probe the dark mass distribution in the universe. Building on earlier studies, we recall how the statistics of the convergence field are...
Analytical Predictions for Statistics of Cosmic Shear: Tests Against Simulations (2003)
Valageas, Patrick, Barber, Andrew J., Munshi, Dipak
Weak gravitational lensing surveys are rapidly becoming important tools to probe directly the mass density fluctuations in the universe and its background dynamics. Earlier studies have shown that it...
Galaxy Clustering and Dark Energy (2003)
Munshi, Dipak, Porciani, Cristiano, Wang, Yun
We study the evolution of galaxy clustering in various cosmological models with quintessence. We investigate how the analytical predictions vary with change of dark energy equation of state $w_X$....
Joint Analysis of CMB Temperature and Polarization Power Spectra (2002)
Munshi, Dipak, Challinor, Anthony D., Doré, Olivier, Mortlock, Daniel J., Efstathiou, George P.
This paper has been withdrawn. It was an early draft submitted prematurely in error. A complete version is to be submitted shortly.
How Sensitive Are Weak Lensing Statistics to Dark Energy Content? (2002)
Future weak lensing surveys will directly probe the clustering of dark matter, in addition to providing a test for various cosmological models. Recent studies have provided us with the tools which...
The weak lensing surveys have the potential to probe directly the clustering statistics of dark matter in the universe. Recent studies have shown that it is possible to predict analytically the whole...
A universal probability distribution function for weak-lensing amplification (2002)
Wang, Yun, Holz, Daniel E., Munshi, Dipak
We present an approximate form for the weak lensing magnification distribution of standard candles, valid for all cosmological models, with arbitrary matter distributions, over all redshifts. Our...
Van Leeuwen, Floor, Challinor, Anthony D., Mortlock, Daniel J., Ashdown, Mark A. J., Hobson, Michael P., Lasenby, Anthony N., ...
We present a harmonic model for the data analysis of an all-sky cosmic microwave background survey, such as Planck, where the survey is obtained through ring-scans of the sky. In this model,...
Error Estimates for Measurements of Cosmic Shear (2000)
In the very near future, weak lensing surveys will map the projected density of the universe in an unbiased way over large regions of the sky. In order to interpret the results of studies it is...
Cosmic Statistics through Weak Lenses (2000)
Many recent studies have demonstrated that scaling arguments, such as the so-called hierarchical {\em ansatz}, are extremely useful in understanding the statistical properties of weak gravitational...
Future weak lensing surveys will directly probe the density fluctuation in the universe. Recent studies have shown how the statistics of the weak lensing convergence field is related to the...
Weak lensing surveys are expected to provide direct measurements of the statistics of the projected dark matter distribution. Most analytical studies of weak lensing statistics have been limited to...
The Statistics of Weak Lensing at Small Angular Scales: Probability Distribution Function (1999)
Weak gravitational lensing surveys have the potential to directly probe mass density fluctuation in the universe. Recent studies have shown that it is possible to model the statistics of the...
Weak Lensing from Strong Clustering (1999)
We investigate the effect of weak gravitational lensing in the limit of small angular scales where projected galaxy clustering is strongly nonlinear. This is the regime likely to be probed by future...
Bias and Hierarchical Clustering (1999)
Coles, Peter, Melott, Adrian, Munshi, Dipak
It is now well established that galaxies are biased tracers of the distribution of matter, although it is still not known what form this bias takes. In local bias models the propensity for a galaxy...
Munshi, Dipak, Coles, Peter, Melott, Adrian L.
We develop a diagrammatic technique to represent the multi-point cumulative probability density function (CPDF) of mass fluctuations in terms of the statistical properties of individual collapsed...
Munshi, Dipak, Coles, Peter, Melott, Adrian L.
The highly nonlinear regime of gravitational clustering is characterized by the presence of scale-invariant form of many-body correlation functions. Useful insights can be obtained by investigating...
Munshi, Dipak, Coles, Peter, Melott, Adrian L.
The highly nonlinear regime of gravitational clustering is characterized by the presence of scale-invariant form of many-body correlation functions. Useful insights can be obtained by investigating...
Generalised Cumulant Correlators and Hierarchical Clustering (1998)
Munshi, Dipak, Melott, Adrian L., Coles, Peter
The cumulant correlators, $C_{pq}$, are statistical quantities that generalise the better-known $S_p$ parameters; the former are obtained from the two-point probability distribution function of the...
Cumulant Correlators in 2D and 3D Scale Free Simulations (1998)
Munshi, Dipak, Melott, Adrian L.
Shape dependence of higher order correlations introduces complication in direct determination of these quantities. For this reason theoretical and observational progress has been restricted in...
Bharadwaj, Somnath, Munshi, Dipak, Souradeep, Tarun
In the context of inflationary scenarios, the observed large angle anisotropy of the Cosmic Microwave Background (CMB) temperature is believed to probe the primordial metric perturbations from...
Modelling the evolution of correlation functions in gravitational clustering (1996)
Munshi, Dipak, Padmanabhan, T.
Padmanabhan (1996) has suggested a model to relate the nonlinear two - point correlation function to the linear two - point correlation function. In this paper, we extend this model in two...
Munshi, Dipak, Souradeep, Tarun, Starobinsky, Alexei A.
Skewness of temperature fluctuations of the cosmic microwave background (CMB) produced by initially Gaussian adiabatic perturbations with the flat (Harrison-Zeldovich) spectrum, which arises due to...
Munshi, Dipak, Sahni, Varun, Starobinsky, Alexei A.
We compare different nonlinear approximations to gravitational clustering in the weakly nonlinear regime, using as a comparative statistic the evolution of non-Gaussianity which can be characterised...