References of "Detal, Alain"
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See detailThe XMM-LSS survey: optical assessment and properties of different X-ray selected cluster classes
Adami, C.; Mazure, A.; Pierre, M. et al

in Astronomy and Astrophysics (2011), 526(A18), 36

XMM and Chandra opened a new area for the study of clusters of galaxies. Not only for cluster physics but also, for the detection of faint and distant clusters that were inaccessible with previous ... [more ▼]

XMM and Chandra opened a new area for the study of clusters of galaxies. Not only for cluster physics but also, for the detection of faint and distant clusters that were inaccessible with previous missions. This article presents 66 spectroscopically confirmed clusters (0.05<z<1.5) within an area of 6 deg2 enclosed in the XMM-LSS survey. Almost two thirds have been confirmed with dedicated spectroscopy only and 10% have been confirmed with dedicated spectroscopy supplemented by literature redshifts. Sub-samples, or classes, of extended-sources are defined in a two-dimensional X-ray parameter space allowing for various degrees of completeness and contamination. We describe the procedure developed to assess the reality of these cluster candidates using the CFHTLS photometric data and spectroscopic information from our own follow-up campaigns. Most of these objects are low mass clusters, hence constituting a still poorly studied population. In a second step, we quantify correlations between the optical properties such as richness or velocity dispersion and the cluster X-ray luminosities. We examine the relation of the clusters to the cosmic web. Finally, we review peculiar structures in the surveyed area like very distant clusters and fossil groups. [less ▲]

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See detailThe XMM-LSS survey: the Class 1 cluster sample over the initial 5 deg(2) and its cosmological modelling
Pacaud, F.; Pierre, M.; Adami, C. et al

in Monthly Notices of the Royal Astronomical Society (2007), 382(3), 1289-1308

We present a sample of 29 galaxy clusters from the XMM-LSS survey over an area of some 5 deg(2) out to a redshift of z = 1.05. The sample clusters, which represent about half of the X-ray clusters ... [more ▼]

We present a sample of 29 galaxy clusters from the XMM-LSS survey over an area of some 5 deg(2) out to a redshift of z = 1.05. The sample clusters, which represent about half of the X-ray clusters identified in the region, follow well-defined X-ray selection criteria and are all spectroscopically confirmed. For all clusters, we provide X-ray luminosities and temperatures as well as masses, obtained from dedicated spatial and spectral fitting. The cluster distribution peaks around z = 0.3 and T = 1.5 keV, half of the objects being groups with a temperature below 2 keV. Our L-X-T(z) relation points towards self-similar evolution, but does not exclude other physically plausible models. Assuming that cluster scaling laws follow self-similar evolution, our number density estimates up to z = 1 are compatible with the predictions of the concordance cosmology and with the findings of previous ROSAT surveys. Our well-monitored selection function allowed us to demonstrate that the inclusion of selection effects is essential for the correct determination of the evolution of the L-X-T relation, which may explain the contradictory results from previous studies. Extensive simulations show that extending the survey area to 10 deg(2) has the potential to exclude the non-evolution hypothesis, but those constraints on more refined intracluster medium models will probably be limited by the large intrinsic dispersion of the L-X-T relation, whatever be the sample size. We further demonstrate that increasing the dispersion in the scaling laws increases the number of detectable clusters, hence generating further degeneracy [in addition to sigma(8), Omega(m), L-X-T(z)] in the cosmological interpretation of the cluster number counts. We provide useful empirical formulae for the cluster mass-flux and mass-count rate relations as well as a comparison between the XMM-LSS mass sensitivity and that of forthcoming Sunyaev-Zel'dovich surveys. [less ▲]

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See detailThe XMM-Large scale structure catalogue: X-ray sources and associated optical data. Version I
Pierre, M.; Chiappetti, L.; Pacaud, F. et al

in Monthly Notices of the Royal Astronomical Society (2007), 382(1), 279-290

Following the presentation of the XMM-Large Scale Structure (XMM-LSS) survey X-ray source detection package by Pacaud et al., we provide the source lists for the first surveyed 5.5 deg(2). The catalogues ... [more ▼]

Following the presentation of the XMM-Large Scale Structure (XMM-LSS) survey X-ray source detection package by Pacaud et al., we provide the source lists for the first surveyed 5.5 deg(2). The catalogues pertain to the [0.5-2] and [2-10] keV bands and contain in total 3385 pointlike or extended sources above a detection likelihood of 15 in either band. The agreement with deep log N-log S is excellent. The main parameters considered are position, count rate, source extent with associated likelihood values. A set of additional quantities such as astrometric corrections and fluxes are further calculated while errors on the position and count rate are deduced from simulations. We describe the construction of the band-merged catalogue allowing rapid subsample selection and easy cross-correlation with external multiwavelength catalogues. A small optical Canada-France-Hawaii Telescope Legacy Survey multiband subset of objects are associated with each source along with an X-ray/optical overlay. We make the full X-ray images available in FITS format. The data are available at the Centre de Donnees de Strasbourg and, in a more extended form, at the Milan XMM-LSS survey data base. [less ▲]

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See detailXMM-LSS catalogue. Version I. (Pierre+, 2007)
Pierre, M.; Chiappetti, L.; Pacaud, F. et al

Textual, factual or bibliographical database (2007)

We provide the source list for the first 5.5 surveyed square degrees of the XMM-LSS, with a total of 3385 point-like or extended sources above a detection likelihood of 15 in either 0.5-2 or 2-10keV bands ... [more ▼]

We provide the source list for the first 5.5 surveyed square degrees of the XMM-LSS, with a total of 3385 point-like or extended sources above a detection likelihood of 15 in either 0.5-2 or 2-10keV bands. The table at CDS contains the main parameters, while further parameters and data products (X-ray images and optical thumbnails) are available in the Milan XMM-LSS database site. (1 data file). [less ▲]

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See detailThe XMM Large-Scale Structure survey: a well-controlled X-ray cluster sample over the D1 CFHTLS area
Pierre, M.; Pacaud, F.; Duc, P. A. et al

in Monthly Notices of the Royal Astronomical Society (2006), 372(2), 591-608

We present the XMM Large-Scale Structure Survey (XMM-LSS) cluster catalogue corresponding to the Canada-France-Hawaii Telescope Legacy Survey D1 area. The list contains 13 spectroscopically confirmed, X ... [more ▼]

We present the XMM Large-Scale Structure Survey (XMM-LSS) cluster catalogue corresponding to the Canada-France-Hawaii Telescope Legacy Survey D1 area. The list contains 13 spectroscopically confirmed, X-ray selected galaxy clusters over 0.8 deg(2) to a redshift of unity and so constitutes the highest density sample of clusters to date. Cluster X-ray bolometric luminosities range from 0.03 to 5 x 10(44) erg s(-1). In this study, we describe our catalogue construction procedure: from the detection of X-ray cluster candidates to the compilation of a spectroscopically confirmed cluster sample with an explicit selection function. The procedure further provides basic X-ray products such as cluster temperature, flux and luminosity. We detected slightly more clusters with (0.5-2.0 keV) X-ray fluxes of > 2 x 10(-14) erg s(-1) cm(-2) than we expected based on expectations from deep ROSAT surveys. We also present the luminosity-temperature relation for our nine brightest objects possessing a reliable temperature determination. The slope is in good agreement with the local relation, yet compatible with a luminosity enhancement for the 0.15 < z < 0.35 objects having 1 < T < 2 keV, a population that the XMM-LSS is identifying systematically for the first time. The present study permits the compilation of cluster samples from XMM images whose selection biases are understood. This allows, in addition to studies of large-scale structure, the systematic investigation of cluster scaling law evolution, especially for low mass X-ray groups which constitute the bulk of our observed cluster population. All cluster ancillary data (images, profiles, spectra) are made available in electronic form via the XMM-LSS cluster data base. [less ▲]

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See detailScience cases for next generation optical/infrared interferometric facilities (the post VLTI era) : Proceedings of the 37th Liège International Astrophysical Colloquium, 23-25 August 2004
Surdej, Jean ULg; Caro, Denise ULg; Detal, Alain ULg

Book published by Sociètè royale des sciences de Liège - Bulletin de la Sociètè royale des sciences de Liège ; v. 74, no. 1-3 (2005)

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See detailThe XMM-LSS survey. Survey design and first results
Pierre, Marguerite; Valtchanov, Ivan; Altieri, Bruno et al

in Journal of Cosmology and Astroparticle Physics [= JCAP] (2004), 09

The XMM Large Scale Structure survey (XMM-LSS) is a medium deep large area X-ray survey. Its goal is to extend large scale structure investigations attempted using ROSAT cluster samples to two redshift ... [more ▼]

The XMM Large Scale Structure survey (XMM-LSS) is a medium deep large area X-ray survey. Its goal is to extend large scale structure investigations attempted using ROSAT cluster samples to two redshift bins between 0<z<1 while maintaining the precision of earlier studies. Two main goals have constrained the survey design: the evolutionary study of the cluster cluster correlation function and of the cluster number density. The adopted observing configuration consists of an equatorial mosaic of 10 ks pointings, separated by 20^\prime and covering 8° à 8°, giving a pointsource sensitivity of {\sim } 5\times 10^{-15}~{\mathrm {erg~cm^{-2}~s^{-1}}} in the 0.5 2 keV band. This will yield more than 800 clusters of galaxies and a sample of X-ray AGN with a space density of about 300 deg[SUP]-2[/SUP]. We present the expected cosmological implications of the survey in the context of LgrCDM models and cluster evolution. We give an overview of the first observational results. The XMM-LSS survey is associated with several other major surveys, ranging from the UV to the radio wavebands, which will provide the necessary resources for X-ray source identification and further statistical studies. In particular, the associated CFHTLS weak lensing and AMiBA Sunyaev Zel'dovich surveys over the entire XMM-LSS area will provide for the first time a comprehensive study of the mass distribution and of cluster physics in the universe on scales of a few hundred Mpc. We describe the main characteristics of our wavelet-based X-ray pipeline and source identification procedures, including the classification of the cluster candidates by means of a photometric redshift analysis. This permits the selection of suitable targets for spectroscopic follow-up. We present preliminary results from the first 25 XMM-LSS pointings: X-ray source properties, optical counterparts, and highlights from the first Magellan and VLT/FORS2 spectroscopic runs as well as preliminary results from the NIR search for z>1 clusters. The results are promising and, so far, in accordance with our predictions. In particular: (1) we reproduce the logN logS distribution for point sources obtained from deeper surveys at our sensitivity; (2) we find a cluster number density of 15 20 deg[SUP]-2[/SUP] (3) for the first time, we statistically sample the group mass regime at a redshift out to {\sim } 0.5 . Paper based on observations obtained with the XMM,CFH, ESO (Prg: P70. A-0283 .A-0733), VLA, CTIO and Las Campanas observatories. [less ▲]

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See detailThe GL bibliography and an interactive database (Poster contribution)
Pospieszalska-Surdej, Anna ULg; Surdej, Jean ULg; Detal, Alain ULg et al

in Brainerd, T. G.; Kochanek, C. S. (Eds.) Proceedings of the Conference "Gravitational lensing: recent progress and future goals" (2001)

It is now possible to directly access, via the Internet, a bibliographical database on Gravitational Lensing (GL) literature. The Interactive Gravitational Lensing Bibliography (IGLB) totalizes more than ... [more ▼]

It is now possible to directly access, via the Internet, a bibliographical database on Gravitational Lensing (GL) literature. The Interactive Gravitational Lensing Bibliography (IGLB) totalizes more than 2400 titles of published articles in scientific journals and meeting proceedings (except those fully dedicated to Gravitational Lenses) as well as papers submitted to the e-Print archive. This database is a product from the Gravitational Lensing Bibliography first presented in 1993 (Proceedings of the 31st Liege International Astrophysical Colloquium). It is easy to do field based searches for title keywords, authors (using boolean operators), year and journal (a pull-down list of the most cited journals is available). Access to the original version of published articles as well as to preprints submitted to the e-Print archive at the URL address http://xxx.lanl.gov/ is also provided. This database is updated approximately every two months. The "complete" bibliography of published articles is also available in the form of Latex and PostScript files. The IGLB can be accessed at the URL: http://vela.astro.ulg.ac.be/grav_lens [less ▲]

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See detailThe GL bibliography and an interactive database
Pospieszalska-Surdej, Anna ULg; Surdej, Jean ULg; Detal, Alain ULg et al

Poster (1999, October 01)

It is now possible to directly access, via the Internet, a bibliographical database on Gravitational Lensing (GL) literature. The Interactive Gravitational Lensing Bibliography (IGLB) totalizes more than ... [more ▼]

It is now possible to directly access, via the Internet, a bibliographical database on Gravitational Lensing (GL) literature. The Interactive Gravitational Lensing Bibliography (IGLB) totalizes more than 2400 titles of published articles in scientific journals and meeting proceedings (except those fully dedicated to Gravitational Lenses) as well as papers submitted to the e-Print archive. This database is a product from the Gravitational Lensing Bibliography first presented in 1993 (Proceedings of the 31st Liege International Astrophysical Colloquium). It is easy to do field based searches for title keywords, authors (using boolean operators), year and journal (a pull-down list of the most cited journals is available). Access to the original version of published articles as well as to preprints submitted to the e-Print archive at the URL address http://xxx.lanl.gov/ is also provided. This database is updated approximately every two months. The "complete" bibliography of published articles is also available in the form of Latex and PostScript files. The IGLB can be accessed at the URL: http://vela.astro.ulg.ac.be/grav_lens [less ▲]

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See detailWolf-Rayet stars in the framework of stellar evolution.
Vreux, Jean-Marie ULg; Detal, Alain ULg; Fraipont-Caro, D. et al

Book (1996)

The following topics were dealt with: evolution of massive stars - theory; observational characteristics of Wolf-Rayet stars and related objects; evidences for evolutionary links - transition objects ... [more ▼]

The following topics were dealt with: evolution of massive stars - theory; observational characteristics of Wolf-Rayet stars and related objects; evidences for evolutionary links - transition objects; analysis of the observations - the models and their results; massive stars in starburst. [less ▲]

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See detailPole, albedo and shape of the minor planets 624 Hektor and 43 Ariadne: Two tests for comparing four different pole determination methods
Detal, Alain ULg; Hainaut, O.; Pospieszalska-Surdej, A. et al

in Astronomy and Astrophysics (1994), 281

Asteroids 624 Hektor and 43 Ariadne have been observed photometrically at the European Southern Observatory (La Silla, Chile) in order to determine their pole orientation. The lightcurves (1984 and 1991 ... [more ▼]

Asteroids 624 Hektor and 43 Ariadne have been observed photometrically at the European Southern Observatory (La Silla, Chile) in order to determine their pole orientation. The lightcurves (1984 and 1991 oppositions for Hektor, and 1985 for Ariadne) are presented. Some of the traditional pole determination methods have been improved, and completely original ones have been developed. They are described and applied to the newly recorded and previously published light curves. The results are commented and compared with previous ones. In addition to the pole orientation, we also derive some information on the shape or the albedo distribtuion of the objects. With the aim of optimizing future observations of these asteroids, we present some graphs showing the best longitudes where they should be measured. Finally, we suggest some improvements in the pole determination and modeling methods based upon photometric data. [less ▲]

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See detailPhotometry, pole orientation and shape parameters of the minor planets 624 Hektor and 43 Ariadne
Detal, Alain ULg; Collette, P.; Hainaut, O. et al

in Brahic, A.; Gérard, J. C.; Surdej, J. (Eds.) "Observations and physical properties of small solar system bodies", 30th Liège International Astrophysical Colloquium, Institut d’Astrophysique, Liège (1992)

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See detailFAS: A new method for deriving the pole orientation and shape parameters of asteroids
Detal, Alain ULg; Schils, P.; Collette, P. et al

in Gérard, Jean-Claude; Surdej, Jean; Brahic, A. (Eds.) "Observations and physical properties of small solar system bodies", 30th Liège International Astrophysical Colloquium, Institut d’Astrophysique, Liège (1992)

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See detailFurther observations of the light echoes from SN 1987 A
Detal, Alain ULg; Surdej, Jean ULg; Hutsemekers, Damien ULg et al

in Astronomy and Astrophysics (1990), 229

Further direct observations of the light echoes from SN 1987 A were obtained on November 12 1988 with the 3.6-m telescope and EFOSC at ESO. In agreement with predictions made from earlier observations ... [more ▼]

Further direct observations of the light echoes from SN 1987 A were obtained on November 12 1988 with the 3.6-m telescope and EFOSC at ESO. In agreement with predictions made from earlier observations, the radii of the two light rings are measured to be 43.3 and 72.5 arcsec. However, a noticeable diaplacement of the center of the outer ring by 2.6 arcsec to the NE from the SN position is also reported. Application of the model of planar-like sheets of material located between the SN and the observer leads to improved results. [less ▲]

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See detailDetermination of the Spin Axis Orientation of Asteroids: Inversion of Photometric Lightcurves
Hainaut, O.; Detal, Alain ULg; Ibrahim-Denis, A. et al

in Lindblad, B. A.; Lagerkvist, C. I.; Rickman, H. (Eds.) Proceedings of a meeting (AMC 89) Asteroids, Comets, Meteors III (1990)

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See detailDetermination of the Spin Vector of a Synthetic Asteroid
Karttunen, H.; Cellino, A.; Detal, Alain ULg et al

in Lindblad; Lagerkvist; Rickman (Eds.) Proceedings of a meeting (AMC 89) Asteroids, Comets, Meteors III (1990)

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See detailInversion of asteroid lightcurves: determination of the pole orientation.
Hainaut, O.; Detal, Alain ULg; Surdej, Jean ULg

in 3. International Symposium on Asteroids, Comets, Meteors, Abstr. 56 (1989, February 01)

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