[Abridged] In this paper we explore a local non-linear perturbative model up to third order as a general characterization of the CMB anisotropies. We focus our analysis in large scale anisotropies....
An introduction to compact source detection in cosmic microwave background images (2009)
We aim to present a tutorial on the detection, parameter estimation and statistical analysis of compact sources (far galaxies, galaxy clusters and Galactic dense emission regions) in cosmic microwave...
Cruz, M., Martinez-Gonzalez, E., Vielva, P.
The WMAP cold spot was found by applying spherical wavelets to the first year WMAP data. An excess of kurtosis of the wavelet coefficient was observed at angular scales of around 5 degrees. This...
Analysis of non-Gaussian CMB maps based on the N-pdf. Application to WMAP data (2008)
We present a new method based on the N-point probability distribution (pdf) to study non-Gaussianity in cosmic microwave background (CMB) maps. Likelihood and Bayesian estimation are applied to a...
Component separation methods for the PLANCK mission (2008)
Leach, S. M., Baccigalupi, C., Barreiro, R. B., Betoule, M., Bobin, J., ...
Context. The PLANCK satellite will map the full sky at nine frequencies from 30 to 857 GHz. The CMB intensity and polarization that are its prime targets are contaminated by foreground emission....
The Quijote CMB Experiment (2008)
Rubino-Martin, J. A., Rebolo, R., Tucci, M., Genova-Santos, R., Hildebrandt, S. R., Hoyland, R., ...
We present the current status of the QUIJOTE (Q-U-I JOint TEnerife) CMB Experiment, a new instrument which will start operations early 2009 at Teide Observatory, with the aim of characterizing the...
A linear filter to reconstruct the ISW effect from CMB and LSS observations (2008)
Barreiro, R. B., Vielva, P., Hernandez-Monteagudo, C., Martinez-Gonzalez, E.
The extraction of a signal from some observational data sets that contain different contaminant emissions, often at a greater level than the signal itself, is a common problem in Astrophysics and...
Component separation methods for the Planck mission (2008)
Leach, S. M., Baccigalupi, C., Barreiro, R. B., Betoule, M., Bobin, J., ...
The Planck satellite will map the full sky at nine frequencies from 30 to 857 GHz. The CMB intensity and polarization that are its prime targets are contaminated by foreground emission. The goal of...
The CMB cold spot: texture, cluster or void? (2008)
Cruz, M., Martinez-Gonzalez, E., Vielva, P., Diego, J. M., Hobson, M., Turok, N.
The non-Gaussian cold spot found in the WMAP data has created controversy about its origin. Here we calculate the Bayesian posterior probability ratios for three different models that could explain...
Non-Gaussianity analysis on local morphological measures of WMAP data (2008)
Wiaux, Y., Vielva, P., Barreiro, R. B., Martínez-González, E., Vandergheynst, P.
The decomposition of a signal on the sphere with the steerable wavelet constructed from the second Gaussian derivative gives access to the orientation, signed-intensity and elongation of the...
A linear filter to reconstruct the ISW effect from CMB and LSS observations (2008)
Barreiro, R. B., Vielva, P., Hernandez-Monteagudo, C., Martinez-Gonzalez, E.
Bianchi VII_h models and the cold spot texture (2007)
Bridges, M., McEwen, J. D., Cruz, M., Hobson, M. P., Lasenby, A. N., Vielva, P., ...
We have returned to our previous Bianchi VII_h analysis in light of the Cruz et al. 2007 suggestion that the cold spot observed near the southern Galactic pole may be a remnant temperature...
Gonzalez-Nuevo, Joaquin, Argueso, Francisco, Lopez-Caniego, Marcos, Toffolatti, Luigi, Sanz, J.L., Vielva, P., ...
We propose a new detection technique in the plane based on an isotropic wavelet family. This family is naturally constructed as an extension of the Gaussian-Mexican Hat Wavelet pair and for that...
Comparison of filters for the detection of point sources in Planck simulations (2007)
Lopez-Caniego, Marcos, Herranz, D., Gonzalez-Nuevo, Joaquin, Sanz, J.L., Barreiro, R.B., Vielva, P., ...
We study the detection of extragalactic point sources in two-dimensional flat simulations for all the frequencies of the forthcoming ESA's Planck mission. In this work we have used the most recent...
A Cosmic Microwave Background feature consistent with a cosmic texture (2007)
Cruz, M., Turok, N., Vielva, P., Martinez-Gonzalez, E., Hobson, M.
The Cosmic Microwave Background provides our most ancient image of the Universe and our best tool for studying its early evolution. Theories of high energy physics predict the formation of various...
A low CMB variance in the WMAP data (2007)
Monteserin, C., Barreiro, R. B., Vielva, P., Martinez-Gonzalez, E., Hobson, M. P., Lasenby, A. N.
We have estimated the CMB variance from the three-year WMAP data, finding a value which is significantly lower than the one expected from Gaussian simulations using the WMAP best-fit cosmological...
Non-Gaussianity analysis on local morphological measures of WMAP data (2007)
Wiaux, Y., Vielva, P., Barreiro, R. B., Martinez-Gonzalez, E., Vandergheynst, P.
The decomposition of a signal on the sphere with the steerable wavelet constructed from the second Gaussian derivative gives access to the orientation, signed-intensity, and elongation of the...
Alignment and signed-intensity anomalies in WMAP data (2007)
Vielva, P., Wiaux, Y., Martinez-Gonzalez, E., Vandergheynst, P.
Significant alignment and signed-intensity anomalies of local features of the cosmic microwave background (CMB) are detected on the three-year WMAP data, through a decomposition of the signal with...
Complex data processing: fast wavelet analysis on the sphere (2007)
Wiaux, Y., McEwen, J. D., Vielva, P.
In the general context of complex data processing, this paper reviews a recent practical approach to the continuous wavelet formalism on the sphere. This formalism notably yields a correspondence...
Cosmological applications of a wavelet analysis on the sphere (2007)
McEwen, J. D., Vielva, P., Wiaux, Y., Barreiro, R. B., Cayon, L., Hobson, M. P., ...
The cosmic microwave background (CMB) is a relic radiation of the Big Bang and as such it contains a wealth of cosmological information. Statistical analyses of the CMB, in conjunction with other...
Complex data processing: fast wavelet analysis on the sphere (2007)
Wiaux, Y., McEwen, J. D., Vielva, P.
In the general context of complex data processing, this paper reviews a recent practical approach to the continuous wavelet formalism on the sphere. This formalism notably yields a correspondence...
Cosmological applications of a wavelet analysis on the sphere (2007)
McEwen, J. D., Vielva, P., Wiaux, Y., Barreiro, R. B., Cayón, L., Hobson, M. P., ...
The cosmic microwave background (CMB) is a relic radiation of the Big Bang and as such it contains a wealth of cosmological information. Statistical analyses of the CMB, in conjunction with other...
Alignment and signed-intensity anomalies in WMAP data (2007)
Vielva, P., Wiaux, Y., Martínez-González, E., Vandergheynst, P.
Significant alignment and signed-intensity anomalies of local features of the cosmic microwave background (CMB) are detected on the three-year WMAP data, through a decomposition of the signal with...
Steerable wavelet analysis of CMB structures alignment (2006)
Vielva, P., Wiaux, Y., Martinez-Gonzalez, E., Vandergheynst, P.
This paper reviews the application of a novel methodology for analysing the isotropy of the universe by probing the alignment of local structures in the CMB. The strength of the proposed methodology...
Knudsen, K. K., Barnard, V. E., Van Der Werf, P. P., Vielva, P., Blain, A. W., ...
Extracting sources with low signal-to-noise from maps with structured background is a non-trivial task which has become important in studying the faint end of the submillimetre number counts. In this...
Comparison of filters for the detection of point sources in Planck simulations (2006)
Lopez-Caniego, M., Herranz, D., Gonzalez-Nuevo, J., Sanz, J. L., Barreiro, R. B., Vielva, P., ...
We study the detection of extragalactic point sources in two-dimensional flat simulations for all the frequencies of the forthcoming ESA's Planck mission. In this work we have used the most recent...
Effect of component separation on the temperature distribution of the CMB (2006)
Barreiro, R.B., Martinez-Gonzalez, E., Vielva, P., Hobson, M.P.
We present a study of the effect of component separation on the recovered cosmic microwave background (CMB) temperature distribution. First, we extract the CMB component from simulated multifrequency...
Detection of the ISW effect and corresponding dark energy constraints (2006)
McEwen, J. D., Vielva, P., Hobson, M. P., Martinez-Gonzalez, E., Lasenby, A. N.
Using a directional spherical wavelet analysis we detect the integrated Sachs-Wolfe (ISW) effect, indicated by a positive correlation between the Wilkinson Microwave Anisotropy Probe (WMAP) and NRAO...
The Mexican Hat Wavelet Family. Application to point source detection in CMB maps (2006)
Gonzalez-Nuevo, J., Argueso, F., Lopez-Caniego, M., Toffolatti, L., Sanz, J. L., Vielva, P., ...
We propose a new detection technique in the plane based on an isotropic wavelet family. This family is naturally constructed as an extension of the Gaussian-Mexican Hat Wavelet pair and for that...
The non-Gaussian Cold Spot in the 3-year WMAP data (2006)
Cruz, M., Cayon, L., Martinez-Gonzalez, E., Vielva, P., Jin, J.
The non-Gaussian cold spot detected in wavelet space in the WMAP 1-year data, is detected again in the coadded WMAP 3-year data at the same position (b = -57, l = 209) and size in the sky (around 10...
Wiaux, Y., Vielva, P., Martinez-Gonzalez, E., Vandergheynst, P.
We question the global universe isotropy by probing the alignment of local structures in the cosmic microwave background (CMB) radiation. The original method proposed relies on a steerable wavelet...
Vielva, P., Martinez-Gonzalez, E., Tucci, M.
We report the detection of the Integrated Sachs-Wolfe effect (ISW) at scales in the sky around [5, 10] degrees with a significance > 3.7 sigma, by cross-correlating the Wilkinson Anisotropy Probe...
Patanchon, G., Delabrouille, J., Vielva, P.
We perform a blind multi-component analysis of the WMAP 1 year foreground cleaned maps using SMICA (Spectral Matching Independent Component Analysis). We provide a new estimate of the CMB power...
McEwen, J. D., Vielva, P., Hobson, M. P., Martinez-Gonzalez, E., Lasenby, A. N.
Using a directional spherical wavelet analysis we detect the integrated Sachs-Wolfe (ISW) effect, indicated by a positive correlation between the first-year Wilkinson Microwave Anisotropy Probe...
Knudsen, K. K., Barnard, V. E., Van Der Werf, P. P., Vielva, P., Blain, A. W., ...
Extracting sources with low signal-to-noise from maps with structured background is a non-trivial task which has become important in studying the faint end of the submillimetre number counts. In this...
The non-Gaussian Cold Spot in WMAP: significance, morphology and foreground contribution (2006)
Cruz, M., Tucci, M., Martinez-Gonzalez, E., Vielva, P.
The non--Gaussian cold spot in the 1-year WMAP data, described in Vielva et al. and Cruz et al., is analysed in detail in the present paper. First of all, we perform a more rigorous calculation of...
Detection of a non-Gaussian Spot in WMAP (2006)
Cruz, M., Martinez-Gonzalez, E., Vielva, P., Cayon, L.
An extremely cold and big spot in the WMAP 1-year data is analyzed. Our work is a continuation of a previous paper (Vielva et al. 2004) where non-Gaussianity was detected, with a method based on the...
Vielva, P., Martinez-Gonzalez, E., Tucci, M.
We report the detection of the Integrated Sachs-Wolfe effect (ISW) at scales in the sky around [5, 10] degrees with a significance > 3.7 sigma, by cross-correlating the Wilkinson Anisotropy Probe...
Vielva, P., Martinez-Gonzalez, E., Tucci, M.
We report the detection of the Integrated Sachs-Wolfe effect (ISW) at scales in the sky around [5, 10] degrees with a significance > 3.7 sigma, by cross-correlating the Wilkinson Anisotropy Probe...
Knudsen, K. K., Barnard, V. E., Van Der Werf, P. P., Vielva, P., Blain, A. W., ...
Extracting sources with low signal-to-noise from maps with structured background is a non-trivial task which has become important in studying the faint end of the submillimetre number counts. In this...
Knudsen, K. K., Barnard, V. E., Van Der Werf, P. P., Vielva, P., Blain, A. W., ...
Extracting sources with low signal-to-noise from maps with structured background is a non-trivial task which has become important in studying the faint end of the submillimetre number counts. In this...
Knudsen, K. K., Barnard, V. E., Van Der Werf, P. P., Vielva, P., Kneib, J. P., Blain, A. W., ...
Extracting sources with low signal-to-noise ratio (S/N) from maps with structured background is a non-trivial task which has become important in studying the faint end of the submillimetre (submm)...
Wiaux, Y., Vielva, P., Martinez-Gonzalez, E., Vandergheynst, P.
We question the global universe isotropy by probing the alignment of local structures in the cosmic microwave background (CMB) radiation. The original method proposed relies on a steerable wavelet...
Steerable wavelet analysis of CMB structures alignment (2006)
Vielva, P., Wiaux, Y., Martinez-Gonzalez, E., Vandergheynst, P.
This paper reviews the application of a novel methodology for analysing the isotropy of the universe by probing the alignment of local structures in the CMB. The strength of the proposed methodology...
The non-Gaussian cold spot detected in wavelet space in the WMAP 1–year data, is detected again in the coadded WMAP 3–year data at the same position (b = −57 ◦ , l = 209 ◦ ) and size in the...
Limits on the detectability of the CMB B-mode polarization imposed by foregrounds (2005)
Tucci, M., Martinez-Gonzalez, E., Vielva, P., Delabrouille, J.
We investigate which practical constraints are imposed by foregrounds to the detection of the B-mode polarization generated by gravitational waves in the case of experiments of the type currently...
The Cosmic Microwave Background anisotropies: open problems (2005)
Martinez-Gonzalez, E., Vielva, P.
The standard inflationary model presents a simple scenario within which the homogeneity, isotropy and flatness of the universe appear as natural outcomes and, in addition, fluctuations in the energy...
Fast directional correlation on the sphere with steerable filters (2005)
Wiaux, Y., Jacques, L., Vielva, P., Vandergheynst, P.
A fast algorithm is developed for the directional correlation of scalar band-limited signals and band-limited steerable filters on the sphere. The asymptotic complexity associated to it through...
Effect of component separation on the temperature distribution of the CMB (2005)
Barreiro, R. B., Martinez-Gonzalez, E., Vielva, P., Hobson, M. P.
We present a study of the effect of component separation on the recovered cosmic microwave background (CMB) temperature distribution, considering Gaussian and non-Gaussian input CMB maps. First, we...
On the excess of power in high resolution CMB experiments (2005)
M. Diego, J., Vielva, P., Martinez-Gonalez, E., Silk, J.
We revisit the possibility that an excess in the CMB power spectrum at small angular scales (CBI, ACBAR) can be due to galaxy clusters (or compact sources in general). We perform a Gaussian analysis...
Effect of component separation on the temperature distribution of the CMB (2005)
Barreiro, R.B., Martinez-Gonzalez, E., Vielva, P., Hobson, M.P.
We present a study of the effect of component separation on the recovered cosmic microwave background (CMB) temperature distribution. First, we extract the CMB component from simulated multifrequency...
Limits on the detectability of the CMB B-mode polarization imposed by foregrounds (2005)
Tucci, M., Martinez-Gonzalez, E., Vielva, P., Delabrouille, J.
We investigate which practical constraints are imposed by foregrounds to the detection of the B-mode polarization generated by gravitational waves in the case of experiments of the type currently...
Detection of a non-Gaussian Spot in WMAP (2005)
Cruz, M., Martinez-Gonzalez, E., Vielva, P., Cayon, L.
An extremely cold and big spot in the WMAP 1-year data is analyzed. Our work is a continuation of a previous paper (Vielva et al. 2004) where non-Gaussianity was detected, with a method based on the...
Patanchon, G., Delabrouille, J., Vielva, P.
We perform a blind multi-component analysis of the WMAP 1 year foreground cleaned maps using SMICA (Spectral Matching Independent Component Analysis). We provide a new estimate of the CMB power...
Effect of component separation on the temperature distribution of the CMB (2005)
Barreiro, R.B., Martinez-Gonzalez, E., Vielva, P., Hobson, M.P.
We present a study of the effect of component separation on the recovered cosmic microwave background (CMB) temperature distribution. First, we extract the CMB component from simulated multifrequency...
Limits on the detectability of the CMB B-mode polarization imposed by foregrounds (2005)
Tucci, M., Martinez-Gonzalez, E., Vielva, P., Delabrouille, J.
We investigate which practical constraints are imposed by foregrounds to the detection of the B-mode polarization generated by gravitational waves in the case of experiments of the type currently...
Detection of a non-Gaussian Spot in WMAP (2005)
Cruz, M., Martinez-Gonzalez, E., Vielva, P., Cayon, L.
An extremely cold and big spot in the WMAP 1-year data is analyzed. Our work is a continuation of a previous paper (Vielva et al. 2004) where non-Gaussianity was detected, with a method based on the...
Patanchon, G., Delabrouille, J., Vielva, P.
We perform a blind multi-component analysis of the WMAP 1 year foreground cleaned maps using SMICA (Spectral Matching Independent Component Analysis). We provide a new estimate of the CMB power...
Moudden, Y., Abrial, P., Vielva, P., ...
Spectral matching ICA (SMICA) is a source separation method based on covariance matching in Fourier space that was designed to address in a flexible way some of the general problems raised by Cosmic...
Moudden, Y., Abrial, P., Vielva, P., ...
Spectral matching ICA (SMICA) is a source separation method based on covariance matching in Fourier space that was designed to address in a flexible way some of the general problems raised by Cosmic...
Moudden, Y., Abrial, P., Vielva, P., ...
Spectral matching ICA (SMICA) is a source separation method based on covariance matching in Fourier space that was designed to address in a flexible way some of the general problems raised by Cosmic...
Limits on the detectability of the CMB B-mode polarization imposed by foregrounds (2004)
Tucci, M., Martinez-Gonzalez, E., Vielva, P., Delabrouille, J.
We investigate which practical constraints are imposed by foregrounds to the detection of the B-mode polarization generated by gravitational waves in the case of experiments of the type currently...
CMB and foregrounds in WMAP first year data (2004)
Patanchon, G., Delabrouille, J., Vielva, P.
We perform a blind multi-component analysis of the WMAP 1 year foreground cleaned maps using SMICA (Spectral Matching Independent Component Analysis). We provide a new estimate of the CMB power...
Vielva, P., Martinez-Gonzalez, E., Tucci, M.
We report the first detection of the ISW effect in wavelet space, at scales in the sky around 7 degrees with a significance of around 3.3 sigma, by cross-correlating the WMAP first-year data and the...
Detection of a non-Gaussian Spot in WMAP (2004)
Cruz, M., Martinez-Gonzalez, E., Vielva, P., Cayon, L.
An extremely cold and big spot in the WMAP 1-year data is analyzed. Our work is a continuation of a previous paper (Vielva et al. 2004) where non-Gaussianity was detected, with a method based on the...
The very bright SCUBA galaxy count: looking for SCUBA galaxies with the Mexican Hat Wavelet (2004)
Barnard, V. E., Vielva, P., Blain, A. W., Barreiro, R. B., Richer, J. S., ...
We present the results of a search for bright high-redshift galaxies in two large SCUBA scan-maps of Galactic regions. A Mexican Hat Wavelet technique was used to locate point sources in these maps,...
On the excess of power in high resolution CMB experiments (2004)
Diego, J. M., Vielva, P., Martinez-Gonalez, E., Silk, J.
We revisit the possibility that an excess in the CMB power spectrum at small angular scales (CBI, ACBAR) can be due to galaxy clusters (or compact sources in general). We perform a Gaussian analysis...
On the excess of power in high resolution CMB experiments (2004)
M. Diego, J., Vielva, P., Martinez-Gonalez, E., Silk, J.
We revisit the possibility that an excess in the CMB power spectrum at small angular scales (CBI, ACBAR) can be due to galaxy clusters (or compact sources in general). We perform a Gaussian analysis...
On the excess of power in high resolution CMB experiments (2004)
M. Diego, J., Vielva, P., Martinez-Gonalez, E., Silk, J.
We revisit the possibility that an excess in the CMB power spectrum at small angular scales (CBI, ACBAR) can be due to galaxy clusters (or compact sources in general). We perform a Gaussian analysis...
Detection of non-Gaussianity in the WMAP 1-year data using spherical wavelets (2003)
Vielva, P., Martinez-Gonzalez, E., Barreiro, R. B., Sanz, J. L., Cayon, L.
A non-Gaussian detection in the WMAP 1-year data is reported. The detection has been found in the combined Q-V-W map proposed by the WMAP team (Komatsu et al. 2003) after applying a wavelet technique...
Foreground separation using a flexible maximum-entropy algorithm: an application to COBE data (2003)
Barreiro, R. B., Hobson, M. P., Banday, A. J., Lasenby, A. N., Stolyarov, V., Vielva, P., ...
A flexible maximum-entropy component separation algorithm is presented that accommodates anisotropic noise, incomplete sky-coverage and uncertainties in the spectral parameters of foregrounds. The...
Martinez-Gonzalez, E., Diego, J. M., Vielva, P., Silk, J.
We apply the iterative Expectation-Maximization algorithm (EM) to estimate the power spectrum of the CMB from multifrequency microwave maps. In addition, we are also able to provide a reconstruction...
Vielva, P., Martinez-Gonzalez, E., Gallegos, J. E., Toffolatti, L., Sanz, J. L.
We present an estimation of the point source (PS) catalogue that could be extracted from the forthcoming ESA Planck mission data. We have applied the Spherical Mexican Hat Wavelet (SMHW) to simulated...
A Bayesian non-parametric method to detect clusters in Planck data (2001)
Diego, J. M., Vielva, P., Martinez-Gonzalez, E., Silk, J., Sanz, J. L.
We show how one may expect a significant number of SZ detections in future Planck data without any of the typical assumptions needed in present component separation methods, such as about the power...
Combining maximum-entropy and the mexican hat wavelet to reconstruct the microwave sky (2001)
Vielva, P., Barreiro, R. B., Hobson, M. P., Martinez-Gonzalez, E., Lasenby, A. N., Sanz, J. L., ...
We present a maximum-entropy method (MEM) and `Mexican Hat' wavelet (MHW) joint analysis to recover the different components of the microwave sky from simulated observations by the ESA Planck...
Predicted Planck Extragalactic Point Source Catalogue (2001)
Vielva, P., Martinez-Gonzalez, E., Cayon, L., Diego, J. M., Sanz, J. L., Toffolatti, L.
An estimation of the number and amplitude (in flux) of the extragalactic point sources that will be observed by the Planck Mission is presented in this paper. The study is based on the Mexican Hat...
Combined MEM and MHW analysis of CMB observations (2000)
Barreiro, R. B., Vielva, P., Hobson, M. P., Martinez-Gonzalez, E., Lasenby, A. N., Sanz, J. L., ...
We present a combined maximum-entropy method (MEM) and Mexican Hat wavelet (MHW) analysis in order to recover the different components of the microwave sky. We apply this technique to simulated...
Isotropic Wavelets: a Powerful Tool to Extract Point Sources from CMB Maps (1999)
Cayon, L., Sanz, J. L., Barreiro, R. B., Matinez-Gonzalez, E., Vielva, P., Toffolatti, L., ...
It is the aim of this paper to introduce the use of isotropic wavelets to detect and determine the flux of point sources appearing in CMB maps. The most suited wavelet to detect point sources...