The Skeleton: Connecting Large Scale Structures to Galaxy Formation (2009)
Pichon, Christophe, Gay, Christophe, Pogosyan, Dmitry, Prunet, Simon, Sousbie, Thierry, Colombi, Stephane, ...
We report on two quantitative, morphological estimators of the filamentary structure of the Cosmic Web, the so-called global and local skeletons. The first, based on a global study of the matter...
Probing magnetic fields with multi-frequency polarized synchrotron emission (2009)
Thiebaut, Jerome, Prunet, Simon, Pichon, Christophe, Thiébaut, Eric
We investigate the problem of probing the local spatial structure of the magnetic field of the interstellar medium using multi-frequency polarized maps of the synchrotron emission at radio...
Pogosyan, Dmitri, Gay, Christophe, Pichon, Christophe
The full moments expansion of the joint probability distribution of an isotropic random field, its gradient and invariants of the Hessian is presented in 2 and 3D. It allows for explicit expression...
Cosmic star-formation history from a non-parametric inversion of infrared galaxy counts (2009)
Borgne, Damien Le, Elbaz, David, Ocvirk, Pierre, Pichon, Christophe
[Abridged] This paper aims at providing new conservative constraints to the cosmic star-formation history from the empirical modeling of mid- and far-infrared data. We perform a non-parametric...
Touchon, Marie, Hoede, Claire, Tenaillon, Olivier, Barbe, Valérie, Baeriswyl, Simon, Bidet, Philippe, ...
The Escherichia coli species represents one of the best-studied model organisms, but also encompasses a variety of commensal and pathogenic strains that diversify by high rates of genetic change. We...
Touchon, Marie, Hoede, Claire, Tenaillon, Olivier, Barbe, Valérie, Baeriswyl, Simon, Bidet, Philippe, ...
The Escherichia coli species represents one of the best-studied model organisms, but also encompasses a variety of commensal and pathogenic strains that diversify by high rates of genetic change. We...
Touchon, Marie, Hoede, Claire, Tenaillon, Olivier, Barbe, Valérie, Baeriswyl, Simon, Bidet, Philippe, ...
The Escherichia coli species represents one of the best-studied model organisms, but also encompasses a variety of commensal and pathogenic strains that diversify by high rates of genetic change. We...
Probing magnetic fields with multi-frequency polarized synchrotron emission (2009)
Thiebaut, Jerome, Prunet, Simon, Pichon, Christophe, Thiébaut, Eric
We investigate the problem of probing the local spatial structure of the magnetic field of the interstellar medium using multi-frequency polarized maps of the synchrotron emission at radio...
Probing magnetic fields with multi-frequency polarized synchrotron emission (2009)
Thiebaut, Jerome, Prunet, Simon, Pichon, Christophe, Thiébaut, Eric
We investigate the problem of probing the local spatial structure of the magnetic field of the interstellar medium using multi-frequency polarized maps of the synchrotron emission at radio...
Accurate estimators of power spectra in N-body simulations (2008)
Colombi, Stephane, Jaffe, Andrew H., Novikov, Dmitri, Pichon, Christophe
abridged] A method to rapidly estimate the Fourier power spectrum of a point distribution is presented. This method relies on a Taylor expansion of the trigonometric functions. It yields the Fourier...
Full-Sky Weak Lensing Simulation with 70 Billion Particles (2008)
Teyssier, Romain, Pires, Sandrine, Prunet, Simon, Aubert, Dominique, Pichon, Christophe, Amara, Adam, ...
We have performed a 70 billion dark-matter particles N-body simulation in a 2 $h^{-1}$ Gpc periodic box, using the concordance, cosmological model as favored by the latest WMAP3 results. We have...
Numerical investigation of lenses with substructures using the perturbative method (2008)
Peirani, Sébastien, Alard, Christophe, Pichon, Christophe, Gavazzi, Raphael, Aubert, Dominique
We present a statistical study of the effects induced by substructures on the deflection potential of dark matter halos in the strong lensing regime. This investigation is based on the pertubative...
Numerical investigation of lenses with substructures using the perturbative method (2008)
Peirani, Sébastien, Alard, Christophe, Pichon, Christophe, Gavazzi, Raphael, Aubert, Dominique
We present a statistical study of the effects induced by substructures on the deflection potential of dark matter halos in the strong lensing regime. This investigation is based on the pertubative...
Numerical investigation of lenses with substructures using the perturbative method (2008)
Peirani, Sébastien, Alard, Christophe, Pichon, Christophe, Gavazzi, Raphael, Aubert, Dominique
We present a statistical study of the effects induced by substructures on the deflection potential of dark matter halos in the strong lensing regime. This investigation is based on the pertubative...
Numerical investigation of lenses with substructures using the perturbative method (2008)
Peirani, Sébastien, Alard, Christophe, Pichon, Christophe, Gavazzi, Raphael, Aubert, Dominique
We present a statistical study of the effects induced by substructures on the deflection potential of dark matter halos in the strong lensing regime. This investigation is based on the pertubative...
Numerical investigation of lenses with substructures using the perturbative method (2008)
Peirani, Sébastien, Alard, Christophe, Pichon, Christophe, Gavazzi, Raphael, Aubert, Dominique
We present a statistical study of the effects induced by substructures on the deflection potential of dark matter halos in the strong lensing regime. This investigation is based on the pertubative...
On the Onset of Stochasticity in $\Lambda$CDM Cosmological Simulations (2008)
Thiebaut, Jerome, Pichon, Christophe, Sousbie, Thierry, Prunet, Simon, Pogosyan, D.
The onset of stochasticity is measured in $\Lambda$CDM cosmological simulations using a set of classical observables. It is quantified as the local derivative of the logarithm of the dispersion of a...
On the Onset of Stochasticity in $\Lambda$CDM Cosmological Simulations (2008)
Thiebaut, Jerome, Pichon, Christophe, Sousbie, Thierry, Prunet, Simon, Pogosyan, D.
The onset of stochasticity is measured in $\Lambda$CDM cosmological simulations using a set of classical observables. It is quantified as the local derivative of the logarithm of the dispersion of a...
On the Onset of Stochasticity in $\Lambda$CDM Cosmological Simulations (2008)
Thiebaut, Jerome, Pichon, Christophe, Sousbie, Thierry, Prunet, Simon, Pogosyan, D.
The onset of stochasticity is measured in $\Lambda$CDM cosmological simulations using a set of classical observables. It is quantified as the local derivative of the logarithm of the dispersion of a...
Numerical investigation of lenses with substructures using the perturbative method (2008)
Peirani, Sébastien, Alard, Christophe, Pichon, Christophe, Gavazzi, Raphael, Aubert, Dominique
We present a statistical study of the effects induced by substructures on the deflection potential of dark matter halos in the strong lensing regime. This investigation is based on the pertubative...
Numerical investigation of lenses with substructures using the perturbative method (2008)
Peirani, Sébastien, Alard, Christophe, Pichon, Christophe, Gavazzi, Raphael, Aubert, Dominique
We present a statistical study of the effects induced by substructures on the deflection potential of dark matter halos in the strong lensing regime. This investigation is based on the pertubative...
Small RNA gene identification and mRNA target predictions in bacteria (2008)
Pichon, Christophe, Felden, Brice
Motivation: Bacterial small ribonucleic acids (sRNAs) that are not ribosomal and transfer or messenger RNAs were initially identified in the sixties, whereas their molecular functions are still under...
Aubert, Dominique, Pichon, Christophe
In a serie of three papers, the dynamical interplay between environments and dark matter haloes is investigated, while focussing on the dynamical flows through their virial sphere. Our method relies...
The 3D skeleton of the SDSS (2006)
Sousbie, Thierry, Pichon, Christophe, Courtois, Hélène, Colombi, Stéphane, Novikov, Dmitri
The length of the three-dimensional filaments observed in the fourth public data-release of the SDSS is measured using the {\em local skeleton} method. It consists in defining the set of points where...
Pichon, Christophe, Aubert, Dominique
We investigate statistically the dynamical consequences of cosmological fluxes of matter and related moments on progenitors of today's dark matter haloes. Their dynamics is described via canonical...
The warm-hot intergalactic medium at z~2.2: Metal enrichment and ionization source (2005)
Bergeron, Jacqueline, Aracil, Bastien, Petitjean, Patrick, Pichon, Christophe
Results are presented for our search for warm-hot gas towards the quasar Q 0329-385. We identify ten OVI systems of which two are within 5000 km/s of z_em and a third one should be of intrinsic...
The origin and implications of dark matter anisotropic cosmic infall on ~L* haloes (2005)
Aubert, Dominique, Pichon, Christophe, Colombi, Stephane
We measure the anisotropy of dark matter flows on small scales in the near environment of haloes using a large set of simulations. We rely on two different approaches to quantify the anisotropy of...
Metals in the Intergalactic Medium (2005)
Aracil, Bastien, Petitjean, Patrick, Pichon, Christophe, Bergeron, Jacqueline
We use high spectral resolution (R=45000) and high signal-to-noise ratio (S/N \\~ 35-70 per pixel) spectra of 19 high-redshift (2.1
Modelling and interpreting optical spectra of galaxies at R=10000 (2005)
Lancon, Ariane, Ocvirk, Pierre, Borgne, Damien Le, Pichon, Christophe, Prugniel, Philippe, Fioc, Michel, ...
One way to extract more information from the integrated light of galaxies is to improve the spectral resolution at which observations and analysis are carried out. The population synthesis code...
The origin and implications of dark matter anisotropic cosmic infall on ~L* haloes (2004)
Aubert, Dominique, Pichon, Christophe, Colombi, Stephane
We measure the anisotropy of dark matter flows on small scales in the near environment of haloes using a large set of simulations. We rely on two different approaches to quantify the anisotropy of...
The origin and implications of dark matter anisotropic cosmic infall on ~L* haloes (2004)
Aubert, Dominique, Pichon, Christophe, Colombi, Stephane
We measure the anisotropy of dark matter flows on small scales in the near environment of haloes using a large set of simulations. We rely on two different approaches to quantify the anisotropy of...
The origin and implications of dark matter anisotropic cosmic infall on ~L* haloes (2004)
Aubert, Dominique, Pichon, Christophe, Colombi, Stephane
We measure the anisotropy of dark matter flows on small scales in the near environment of haloes using a large set of simulations. We rely on two different approaches to quantify the anisotropy of...
The origin and implications of dark matter anisotropic cosmic infall on ~L* haloes (2004)
Aubert, Dominique, Pichon, Christophe, Colombi, Stephane
We measure the anisotropy of dark matter flows on small scales in the near environment of haloes using a large set of simulations. We rely on two different approaches to quantify the anisotropy of...
Metals in the Intergalactic Medium (2004)
Aracil, Bastien, Petitjean, Patrick, Pichon, Christophe, Bergeron, Jacqueline
We use high spectral resolution (R=45000) and high signal-to-noise ratio (S/N \\~ 35-70 per pixel) spectra of 19 high-redshift (2.1
The origin and implications of dark matter anisotropic cosmic infall on ~L* haloes (2004)
Aubert, Dominique, Pichon, Christophe, Colombi, Stephane
We measure the anisotropy of dark matter flows on small scales in the near environment of haloes using a large set of simulations. We rely on two different approaches to quantify the anisotropy of...
Metals in the Intergalactic Medium (2004)
Aracil, Bastien, Petitjean, Patrick, Pichon, Christophe, Bergeron, Jacqueline
We use high spectral resolution (R=45000) and high signal-to-noise ratio (S/N \\~ 35-70 per pixel) spectra of 19 high-redshift (2.1
The origin and implications of dark matter anisotropic cosmic infall on ~L* haloes (2004)
Aubert, Dominique, Pichon, Christophe, Colombi, Stephane
We measure the anisotropy of dark matter flows on small scales in the near environment of haloes using a large set of simulations. We rely on two different approaches to quantify the anisotropy of...
The origin and implications of dark matter anisotropic cosmic infall on ~L* haloes (2004)
Aubert, Dominique, Pichon, Christophe, Colombi, Stephane
We measure the anisotropy of dark matter flows on small scales in the near environment of haloes using a large set of simulations. We rely on two different approaches to quantify the anisotropy of...
The Clustering of Intergalactic Metals (2003)
Pichon, Christophe, Scannapieco, Evan, Aracil, Bastien, Petitjean, Patrick, Aubert, Dominique, Bergeron, Jacqueline, ...
We measure the spatial clustering of metals in the intergalactic medium from z = 1.7 to 3.0, as traced by 643 CIV and 104 SiIV N >= 10^12 cm^-2 absorption systems in 19 high signal-to-noise (40-80)...
Metals in the Intergalactic Medium (2003)
Aracil, Bastien, Petitjean, Patrick, Pichon, Christophe, Bergeron, Jacqueline
We use high spectral resolution (R=45000) and high signal-to-noise ratio (S/N \~ 35-70 per pixel) spectra of 19 high-redshift (2.1
sources of intergalactic metals Elektronische Daten (2003)
Scannapieco, Evan, Pichon, Christophe, Astrophysics Conference
Talk Abstract von Kongress: Star and Structure Formation: From First Light to the Milky Way, Astrophysics Conference, August 18-22, 2003, ETH Zurich, Switzerland
Intergenic sequence inspector: searching and identifying bacterial RNAs (2003)
Pichon, Christophe, Felden, Brice
Summary:Intergenic Sequence Inspector (ISI) is a program that helps in identifying bacterial ribonucleic acids (RNAs). It automatically extracts, selects and visualizes candidate intergenic regions...
The warm-hot intergalactic medium at z~2.2: Metal enrichment and ionization source (2002)
Bergeron, Jacqueline, Aracil, Bastien, Petitjean, Patrick, Pichon, Christophe
Results are presented for our search for warm-hot gas towards the quasar Q 0329-385. We identify ten OVI systems of which two are within 5000 km/s of z_em and a third one should be of intrinsic...
The warm-hot intergalactic medium at z~2.2: Metal enrichment and ionization source (2002)
Bergeron, Jacqueline, Aracil, Bastien, Petitjean, Patrick, Pichon, Christophe
Results are presented for our search for warm-hot gas towards the quasar Q 0329-385. We identify ten OVI systems of which two are within 5000 km/s of z_em and a third one should be of intrinsic...
The warm-hot intergalactic medium at z~2.2: Metal enrichment and ionization source (2002)
Bergeron, Jacqueline, Aracil, Bastien, Petitjean, Patrick, Pichon, Christophe
Results are presented for our search for warm-hot gas towards the quasar Q 0329-385. We identify ten OVI systems of which two are within 5000 km/s of z_em and a third one should be of intrinsic...
3D Spatial Distribution of the Intergalactic Medium (2001)
Petitjean, Patrick, Rollinde, Emmanuel, Aracil, Bastien, Pichon, Christophe, Colombi, Stéphane
Very recently a new inversion method has been developped to analyze the intergalactic medium seen in absorption in quasar spectra (the so-called Lyman-alpha forest). This method is applied to recover...
Th. doct. : Chimie-physique : Dijon : 1999.
Dynamics of self-gravitating disks. (1994)
Thesis (Ph. D.)--University of Cambridge, 1994.
La Décentralisation en matière de tourisme / (1990)
Mémoire de DEA : Droit public interne / Paris 2 ; session de février 1991.
Pichon, Christophe, Felden, Brice
Small RNA (sRNA) genes are expressed in all organisms, primarily as regulators of translation and message stability. We have developed comparative genomic approaches to identify sRNAs that are...
Pichon, Christophe, Felden, Brice
Small RNA (sRNA) genes are expressed in all organisms, primarily as regulators of translation and message stability. We have developed comparative genomic approaches to identify sRNAs that are...
Organised Genome Dynamics in the Escherichia coli Species Results in Highly Diverse Adaptive Paths
Touchon, Marie, Hoede, Claire, Tenaillon, Olivier, Barbe, Valérie, Baeriswyl, Simon, Bidet, Philippe, ...
The Escherichia coli species represents one of the best-studied model organisms, but also encompasses a variety of commensal and pathogenic strains that diversify by high rates of genetic change. We...