Curto, A., Martinez-Gonzalez, E., Barreiro, R. B.
We present new constraints on the non-linear coupling parameter fnl with the Wilkinson Microwave Anisotropy Probe (WMAP) data. We use a method based on the spherical Mexican hat wavelet (SMHW) which...
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...
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...
WMAP 5-year constraints on fnl with wavelets (2008)
Curto, A., Martinez-Gonzalez, E., Mukherjee, P., Barreiro, R. B., Hansen, F. K., Liguori, M., ...
We present a Gaussianity analysis of the WMAP 5-year Cosmic Microwave Background (CMB) temperature anisotropy data maps. We use several third order estimators based on the spherical Mexican hat...
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...
Constraints on the non-linear coupling parameter fnl with the Archeops data (2008)
Curto, A., Macias-Perez, J. F., Martinez-Gonzalez, E., Barreiro, R. B., Santos, D., Hansen, F. K., ...
We present a Gaussianity analysis of the Archeops Cosmic Microwave Background (CMB) temperature anisotropy data maps at high resolution to constrain the non-linear coupling parameter fnl...
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...
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...
Testing gaussianity on Archeops data (2007)
Curto, A., Aumont, J., Macias-Perez, J.F., Martinez-Gonzalez, E., Barreiro, R.B., Santos, D., ...
A Gaussianity analysis using a goodness-of-fit test has been performed to study the measured Archeops Cosmic Microwave Background (CMB) temperature anisotropy data for a 143 GHz Archeops bolometer....
Testing gaussianity on Archeops data (2007)
Curto, A., Aumont, J., Macias-Perez, J.F., Martinez-Gonzalez, E., Barreiro, R.B., Santos, D., ...
A Gaussianity analysis using a goodness-of-fit test has been performed to study the measured Archeops Cosmic Microwave Background (CMB) temperature anisotropy data for a 143 GHz Archeops bolometer....
Testing gaussianity on Archeops data (2007)
Curto, A., Aumont, J., Macias-Perez, J.F., Martinez-Gonzalez, E., Barreiro, R.B., Santos, D., ...
A Gaussianity analysis using a goodness-of-fit test has been performed to study the measured Archeops Cosmic Microwave Background (CMB) temperature anisotropy data for a 143 GHz Archeops bolometer....
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...
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...
Testing Gaussianity on Archeops Data (2006)
Curto, A., Aumont, J., Macias-Perez, J. F., Martinez-Gonzalez, E., Barreiro, R. B., Santos, D., ...
A Gaussianity analysis using a goodness-of-fit test and the Minkowski functionals on the sphere has been performed to study the measured Archeops Cosmic Microwave Background (CMB) temperature...
Gaussian analysis of the CMB with the smooth tests of goodness of fit (2006)
Barreiro, R. B., Rubino-Martin, J. A., Martinez-Gonzalez, E.
The study of the Gaussianity of the cosmic microwave background (CMB) radiation is a key topic to understand the process of structure formation in the Universe. In this paper, we review a very useful...
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...
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...
Scalar quantities as detectors of non-Gaussianity on CMB maps (2006)
Monteserin, C., Barreiro, R. B., Martinez-Gonzalez, E., Sanz, J. L.
We study the power of several scalar quantities constructed on the sphere (presented in Monteserin et al. 2005) to detect non-Gaussianity on the temperature distribution of the cosmic microwave...
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...
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...
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...
Calibration and testing of the Planck-LFI QM instrument (2006)
Mennella, A., Aja, B., Artal, E., Balasini, M., Baldan, G., Battaglia, P., ...
Proceedings of SPIE. Vol. 6265, 62650G
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...
Scalar statistics on the sphere: application to the CMB (2005)
Monteserin, C., Barreiro, R. B., Sanz, J. L., Martinez-Gonzalez, E.
A method to compute several scalar quantities of Cosmic Microwave Background maps on the sphere is presented. We consider here four type of scalars: the Hessian matrix scalars, the distortion...
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...
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...
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...
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...
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...
Gaussianity of the CMB: Smooth Goodness of Fit Tests Applied to Interferometric Data (2004)
Aliaga, A. M., Rubino-Martin, J. A., Martinez-Gonzalez, E., Barreiro, R. B., Sanz, J. L.
We adapt the smooth tests of goodness of fit developed by Rayner and Best to the study of the non-Gaussianity of interferometric observations of the cosmic microwave background (CMB). The...
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...
Aliaga, A. M., Martinez-Gonzalez, E., Cayon, L., Argueso, F., Sanz, J. L., Barreiro, R. B., ...
We review two powerful methods to test the Gaussianity of the cosmic microwave background (CMB): one based on the distribution of spherical wavelet coefficients and the other on smooth tests of...
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...
Goodness-of-fit tests of Gaussianity: constraints on the cumulants of the MAXIMA data (2003)
Aliaga, A. M., Martinez-Gonzalez, E., Cayon, L., Argueso, F., Sanz, J. L., Barreiro, R. B.
In this work, goodness-of-fit tests are adapted and applied to CMB maps to detect possible non-Gaussianity. We use Shapiro-Francia test and two Smooth goodness-of-fit tests: one developed by Rayner...
Goodness-of-fit tests to study the Gaussianity of the MAXIMA data (2003)
Cayon, L., Argueso, F., Martinez-Gonzalez, E., Sanz, J.L.
Goodness-of-fit tests, including smooth ones, are introduced and applied to detecting non-Gaussianity in cosmic microwave background simulations. We study the power of three different tests: the...
Advanced pseudo-correlation radiometers for the Planck-LFI instrument (2003)
Mennella, A., Bersanelli, M., Butler, R. C., Maino, D., Mandolesi, N., Morgante, G., ...
The LFI (Low Frequency Instrument) on board the ESA Planck satellite is constituted by an array of radiometric detectors actively cooled at 20 K in the 30-70 GHz frequency range in the focal plane of...
Tucci, M., Martinez-Gonzalez, E., Toffolatti, L., Gonzalez-Nuevo, J., De Zotti, G.
We present a method to simulate the polarization properties of extragalactic radio sources at microwave frequencies. Polarization measurements of nearly 2x10^6 sources at 1.4 GHz are provided by the...
Goodness-of-Fit Tests to study the Gaussianity of the MAXIMA data (2003)
Cayon, L., Argueso, F., Martinez-Gonzalez, E., Sanz, J. L.
Goodness-of-Fit tests, including Smooth ones, are introduced and applied to detect non-Gaussianity in Cosmic Microwave Background simulations. We study the power of three different tests: the...
Comparing filters for the detection of point sources (2003)
Barreiro, R. B., Sanz, J. L., Herranz, D., Martinez-Gonzalez, E.
This paper considers filters (the Mexican hat wavelet, the matched and the scale-adaptive filters) that optimize the detection/separation of point sources on a background. We make a one-dimensional...
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...
COBE-DMR constraints on the nonlinear coupling parameter: a wavelet based method (2002)
Cayon, L., Martinez-Gonzalez, E., Argueso, F., Banday, A. J., Gorski, K. M.
Nonlinearity introduced in slow-roll inflation will produce weakly non-Gaussian CMB temperature fluctuations. We have simulated non-Gaussian large scale CMB maps (including COBE-DMR constraints)...
Cosmology with GTC. A combined mm-optical galaxy cluster survey (2002)
Diego, J. M., Martinez-Gonzalez, E., Sanz, J. L., Benitez, N., Silk, J.
The CMB Planck satellite (ESA) will provide a catalogue of nearly 30000 galaxy clusters (Sunyaev-Zel'dovich effect) between redshift 0 and approx. 2-3 (depending on the cosmological model). This...
Scale-Adaptive filters for the detection/separation of compact sources (2002)
Herranz, D., Sanz, J. L., Barreiro, R. B., Martinez-Gonzalez, E.
This paper presents scale-adaptive filters that optimize the detection/separation of compact sources on a background. We assume that the sources have a multiquadric profile, i. e. $\tau (x) = {[1 +...
Herranz, D., Gallegos, J., Sanz, J. L., Martinez-Gonzalez, E.
Wavelet-related techniques have proven useful in the processing and analysis of one and two dimensional data sets (spectra in the former case, images in the latter). In this work we apply adaptive...
Herranz, D., Sanz, J. L., Hobson, M. P., Barreiro, R. B., Diego, J. M., Martinez-Gonzalez, E., ...
The problem of detecting Sunyaev-Zel'dovich (SZ) clusters in multifrequency CMB observations is investigated using a number of filtering techniques. A multifilter approach is introduced, which...
The performance of spherical wavelets to detect non-Gaussianity in the CMB sky (2001)
Martinez-Gonzalez, E., Gallegos, J. E., Argueso, F., Cayon, L., Sanz, J. L.
We investigate the performance of spherical wavelets in discriminating between standard inflationary models (Gaussian) and non-Gaussian models. For the later we consider small perturbations of the...
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...
Optimal detection of sources on a homogeneous and isotropic background (2001)
Sanz, J. L., Herranz, D., Martinez-Gonzalez, E.
This paper introduces the use of pseudo-filters that optimize the detection/extraction of sources on a background. We assume as a first approach that such sources are described by a spherical...
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...
Spherical Mexican Hat wavelet: an application to detect non-Gaussianity in the COBE-DMR maps (2001)
Cayon, L., Sanz, J. L., Martinez-Gonzalez, E., Banday, A. J., Argueso, F., Gallegos, J. E., ...
The spherical Mexican Hat wavelet is introduced in this paper, with the aim of testing the Gaussianity of the Cosmic Microwave Background temperature fluctuations. Using the information given by the...
A joint fit to the cosmological Model and the T-M and L_x-T relations using cluster data (2001)
Diego, J. M., Martinez-Gonzalez, E., Sanz, J. L., Silk, J., Cayon, L., Benitez, N.
In this work we show how well can the cosmological parameters be constrained using galaxy cluster data. We also show how in the process of fitting the model which attempts to describe the data it is...
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...
The SZ effect as a cosmological discriminator (2001)
Diego, J. M., Martinez-Gonzalez, E., Sanz, J. L., Benitez, N., Silk, J.
We show how future measurements of the SZ effect (SZE) can be used to constrain the cosmological parameters. We combine the SZ information expected from the Planck full-sky survey, N(S), where no...
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...
Strong constraints on cosmology from galaxy clusters (2000)
Diego, J. M., Martinez-Gonzalez, E., Sanz, J. L., Cayon, L., Silk, J.
In this work we show how galaxy clusters can be used to discriminate among different cosmological models. We have used available X-ray & optical cluster data to constrain the cosmological parameters...
Tests of Gaussianity of CMB maps (2000)
Martinez-Gonzalez, E., Barreiro, B., Diego, J. M., Sanz, J. L., Cayon, L., Silk, J., ...
We study two different methods to test Gaussianity in CMB maps. One of them is based on the partition function and the other on the morphology of hot and cold spots. The partition function contains...
Geometrical estimators as a test of Gaussianity in the CMB (2000)
Barreiro, R. B., Martinez-Gonzalez, E., Sanz, J. L.
We investigate the power of geometrical estimators on detecting non-Gaussianity in the cosmic microwave background. In particular the number, eccentricity and Gaussian curvature of excursion sets...
Constraining our Universe with X-ray & Optical Cluster Data (2000)
Diego, J. M., Martinez-Gonzalez, E., Sanz, J. L., Cayon, L., Silk, J.
We have used recent X-ray and optical data in order to impose some constraints on the cosmology and cluster scaling relations. Generically two kind of hypotheses define our model. First we consider...
Quasar-galaxy associations revisited (2000)
Benitez, N., Sanz, J. L., Martinez-Gonzalez, E.
Gravitational lensing predicts an enhancement of the density of bright, distant QSOs around foreground galaxies. We measure this QSO-galaxy correlation w_qg for two complete samples of radio-loud...
Constraints on Cluster Properties Using X-ray and Optical Data (2000)
Diego, J. M., Martinez-Gonzalez, E., Sanz, J. L., Cayon, L., Silk, J.
In this work we show that combining different cluster data sets is a powerful tool to constrain both, the cosmology and cluster properties. We assume a model with 9 parameters and fit them to 5...
Analysis of CMB maps with 2D wavelets (1999)
Sanz, J. L., Barreiro, R. B., Cayon, L., Martinez-Gonzalez, E., Ruiz, G. A., Diaz, F. J., ...
We consider the 2D wavelet transform with two scales to study sky maps of temperature anisotropies in the cosmic microwave background radiation (CMB). We apply this technique to simulated maps of...
Wavelets Applied to CMB Maps: a Multiresolution Analysis for Denoising (1999)
Sanz, J. L., Argueso, F., Cayon, L., Martinez-Gonzalez, E., Barreiro, R. B., Toffolatti, L.
Analysis and denoising of Cosmic Microwave Background (CMB) maps are performed using wavelet multiresolution techniques. The method is tested on $12^{\circ}.8\times 12^{\circ}.8$ maps with resolution...
The roughness of the last scattering surface (1999)
Mollerach, Silvia, Martinez, Vicent J., Diego, J. M., Martinez-Gonzalez, E., Sanz, J. L., Paredes, Silvestre
We propose an alternative analysis of the microwave background temperature anisotropy maps that is based on the study of the roughness of natural surfaces. We apply it to large angle anisotropies,...
Partition function based analysis of CMB maps (1999)
Diego, J. M., Martinez-Gonzalez, E., Sanz, J. L., Mollerach, S., Martinez, V.
We present an alternative method to analyse cosmic microwave background (CMB) maps. We base our analysis on the study of the partition function. This function is used to examine the CMB maps making...
The optical/IR counterpart of the 3 July 1998 gamma-ray burst and its evolution (1998)
Castro-Tirado, A. J., Zapatero-Osorio, M. R., Gorosabel, J., Greiner, J., Heidt, J., Herranz, D., ...
We imaged the X-ray error box of GRB 980703, beginning 22.5 hours after the gamma--ray event, in both the optical R and near-infrared H bands. A fading optical/IR object was detected within the X-ray...
Segregated Optical-NIR colour distributions of MDS galaxies (1998)
Ferreras, I., Cayon, L., Martinez-Gonzalez, E., Benitez, N.
We present a K survey of 29 fields covering approximately 90 arcmin^2 from the Medium Deep Survey (MDS) catalogue down to a completeness magnitude of K=18.0 (limiting magnitude K=19.0). The...
Imaging around PC1643+4631A at the Lyman limit (1998)
Ferreras, I., Benitez, N., Martinez-Gonzalez, E.
We present a list of candidates for high redshift late-type galaxies in the field around the z=3.79 quasar PC1643+4631A. Deep U,V and R imaging has been used to search for objects with a strong Lyman...
Correlation of Excursion Sets for Non-Gaussian CMB Temperature Distributions (1997)
Barreiro, R. B., Sanz, J. L., Martinez-Gonzalez, E., Silk, J.
We present a method, based on the correlation function of excursion sets above a given threshold, to test the Gaussianity of the CMB temperature fluctuations in the sky. In particular, this method...
Are optically-selected QSO catalogs biased ? (1997)
Ferreras, I., Benitez, N., Martinez-Gonzalez, E.
A thorough study of QSO-galaxy correlations has been done on a region close to the North Galactic Pole using a complete subsample of the optically selected CFHT/MMT QSO survey and the galaxy catalog...
Weak lensing correlations in open and flat universes (1997)
Sanz, J. L., Martinez-Gonzalez, E., Benitez, N.
Correlations between the magnification or polarization of background sources, induced by gravitational lensing due to the large-scale structure, and the positions of foreground galaxies are...
Statistical excess of foreground galaxies around high-z radiogalaxies (1997)
Benitez, N., Martinez-Gonzalez, E., Martin-Mirones, J. M.
K-band imaging of a sample of 21 radiogalaxies with z \sim 1.5 reveals the existence of a statistical association of foreground galaxies with the positions of the radiosources. The excess is detected...
Peaks in the Cosmic Microwave Background: flat versus open models (1996)
Barreiro, R. B., Sanz, J. L., Martinez-Gonzalez, E., Cayon, L., Silk, Joseph
We present properties of the peaks (maxima) of the CMB anisotropies expected in flat and open CDM models. We obtain analytical expressions of several topological descriptors: mean number of maxima...
The absorbers towards Q0836+113 (1996)
Benitez, N., Martinez-Gonzalez, E., Sanz, J. L., Aguirre, A., Alises, M.
We have performed RIJHK_S imaging of the field around the z=2.67 quasar Q0836+113, which presents several metal line and a damped Ly\alpha absorption systems in its spectrum. The images reveal the...
Large Scale QSO-galaxy correlations for radio loud and optically selected QSO samples (1996)
Benitez, N., Martinez-Gonzalez, E.
We have studied the distribution of $B_J0.3$ QSOs with similar redshift distributions. The first sample is formed by 144 radio-loud QSOs from the Parkes Catalogue, and the other contains 167...
Omega from the COBE-DMR anisotropy maps (1995)
Cayon, L., Martinez-Gonzalez, E., Sanz, J. L., Sugiyama, N., Torres, S.
We have made a likelihood statistical analysis of the angular correlations in the {\it COBE}-DMR two-year sky maps by Monte Carlo simulation of the temperature fluctuations. We assume an open...
High redshift AGNs from the 1Jy catalogue and the magnification bias (1995)
Benitez, N., Martinez-Gonzalez, E.
We have found a statistically significant (99.1 \%) excess of red ($O-E>2$) galaxies with photographic magnitudes $E
INTERMEDIATE RESOLUTION SPECTROSCOPY OF THE RADIO GALAXY B2 0902+34 AT $Z\approx 3.4$ (1995)
Martin-Mirones, J. M., Martinez-Gonzalez, E., Gonzalez-Serrano, J. I., Sanz, J. L.
We have carried out spectroscopic observations of the high redshift ($z\approx 3.4$) radio galaxy 0902+34 at intermediate resolution with the William Herschel Telescope. The dynamical spectral ranges...
Genus and spot density in the COBE DMR first year anisotropy maps (1995)
Torres, S., Cayon, L., Martinez-Gonzalez, E., Sanz, J. L.
A statistical analysis of texture on the {\it COBE}-DMR first year sky maps based on the genus and spot number is presented. A generalized $\chi^2$ statistic is defined in terms of ``observable''...
R-Band Imaging of Fields Around 1 (1994)
Benitez, N., Martinez-Gonzalez, E., Gonzalez-Serrano, J. I., Cayon, L.
We have taken deep $R$-band images of fields around five radiogalaxies: 0956+47, 1217+36, 3C256, 3C324 and 3C294 with $1
Goodness-of-fit tests to study the Gaussianity of the MAXIMA data
Cayon, L., Argueso, F., Martinez-Gonzalez, E., Sanz, J.L.
Goodness-of-fit tests, including smooth ones, are introduced and applied to detecting non-Gaussianity in cosmic microwave background simulations. We study the power of three different tests: the...
Goodness-of-fit tests to study the Gaussianity of the MAXIMA data
Cayon, L., Argueso, F., Martinez-Gonzalez, E., Sanz, J.L.
Goodness-of-fit tests, including smooth ones, are introduced and applied to detecting non-Gaussianity in cosmic microwave background simulations. We study the power of three different tests: the...