Damped and sub-damped Lyman-? absorbers in z > 4 QSOs (2009)
Guimaraes, Rodney, Petitjean, Patrick, De Carvalho, Reinaldo Ramos, Djorgovski, George, Noterdaeme, Pasquier, Castro, Sandra, ...
We present the results of a survey for damped (DLA, log N(H I) > 20.3) and sub-damped Lyman-? systems (19.5 < log N(H I) < 20.3) at z > 2.55 along the lines-of-sight to 77 quasars with emission...
Vergani, Susanna D., Petitjean, Patrick, Ledoux, Cedric, Vreeswijk, Paul, Smette, Alain, Meurs, Evert J. A.
We analyse the properties of MgII absorption systems detected along the sightlines toward GRBs using a sample of 10 GRB afterglow spectra obtained with VLT-UVES over the past six years. The S/N ratio...
Constraining fundamental constants of physics with quasar absorption line systems (2009)
Petitjean, Patrick, Srianand, Raghunathan, Chand, Hum, Ivanchik, Alexander, Noterdaeme, Pasquier, Gupta, Neeraj
We summarize the attempts by our group and others to derive constraints on variations of fundamental constants over cosmic time using quasar absorption lines. Most upper limits reside in the range...
Fox, Andrew J., Prochaska, J. Xavier, Ledoux, Cédric, Petitjean, Patrick, Wolfe, Arthur M., Srianand, Raghunathan
We continue our recent work to characterize the plasma content of high-redshift damped and sub-damped Lyman-alpha systems (DLAs/sub-DLAs), which represent multi-phase gaseous (proto)galactic disks...
Damped and sub-damped Lyman-α absorbers in z > 4 QSOs (2009)
Guimaraes, Rodney, Petitjean, Patrick, De Carvalho, Reinaldo, Djorgovski, George, Noterdaeme, Pasquier, Castro, Sandra, ...
We present the results of a survey for damped (DLA, log N(H I) > 20.3) and sub-damped Lyman-α systems (19.5 < log N(H I) < 20.3) at z > 2.55 along the lines-of-sight to 77 quasars with emission...
Damped and sub-damped Lyman-α absorbers in z > 4 QSOs (2009)
Guimaraes, Rodney, Petitjean, Patrick, De Carvalho, Reinaldo, Djorgovski, George, Noterdaeme, Pasquier, Castro, Sandra, ...
We present the results of a survey for damped (DLA, log N(H I) > 20.3) and sub-damped Lyman-α systems (19.5 < log N(H I) < 20.3) at z > 2.55 along the lines-of-sight to 77 quasars with emission...
Damped and sub-damped Lyman-α absorbers in z > 4 QSOs (2009)
Guimaraes, Rodney, Petitjean, Patrick, De Carvalho, Reinaldo, Djorgovski, George, Noterdaeme, Pasquier, Castro, Sandra, ...
We present the results of a survey for damped (DLA, log N(H I) > 20.3) and sub-damped Lyman-α systems (19.5 < log N(H I) < 20.3) at z > 2.55 along the lines-of-sight to 77 quasars with emission...
Damped and sub-damped Lyman-α absorbers in z > 4 QSOs (2009)
Guimaraes, Rodney, Petitjean, Patrick, De Carvalho, Reinaldo, Djorgovski, George, Noterdaeme, Pasquier, Castro, Sandra, ...
We present the results of a survey for damped (DLA, log N(H I) > 20.3) and sub-damped Lyman-α systems (19.5 < log N(H I) < 20.3) at z > 2.55 along the lines-of-sight to 77 quasars with emission...
A Study of Quasar Proximity in O VI Absorbers at z=2-3 (2008)
Fox, Andrew J., Bergeron, Jacqueline, Petitjean, Patrick
(Abridged) With the goal of investigating the nature of OVI absorbers at high redshifts, we study the effects of proximity to the background quasar. In a sample of sixteen quasars at z(QSO) between...
Sciences et croyances : religions, parasciences et scientisme (2008)
BENSAUDE-VINCENT, Bernardette, BOURDEAU, Michel, JURDANT, Baudouin, PETITJEAN, Patrick
The Nitrogen and Oxygen abundances in the neutral gas at high redshift (2007)
Petitjean, Patrick, Ledoux, Cedric, Srianand, R.
We study the Oxygen and Nitrogen abundances in the interstellar medium of high-redshift galaxies. We use high resolution and high signal-to-noise ratio spectra of Damped Lyman-alpha (DLA) systems...
The Evolution of the Lyman alpha Forest (2007)
Jan Peter Mücket, Patrick Petitjean, Rüdiger Riediger
Introduction Over the past half decade considerable progress has been made in the theoretical understanding of the nature of the Lymanff forest. The common outcome of related investigations (Cen et...
QSO Absorption Lines and the 3D Matter Distribution (2007)
Jan Peter Mücket, Rüdiger Riediger, Patrick Petitjean
erent QSOs separated by some angle ` (see e.g. Petitjean et al. 1998). Using our simulations we have computed the probabilities for line conincidences as function of the separation between two lines...
Reanalysis of the simulated Lyman alpha Forest (2007)
Rüdiger Riediger, Jan Peter Mücket, Patrick Petitjean
ine system again. This continues until a sufficient Ø 2 is reached. This procedure has been applied to computed spectra (see Fig. 1) from our simulation of the Lyff forest (Mucket et al. [3],...
Evolution Of Correlation Functions In Modelled Lyman alpha Forest Spectra (2007)
Rüdiger Riediger, Jan Peter Mücket, Patrick Petitjean
We study the evolution with redshift of the Lymanff forest with a PM-code including photo-ionization and cooling of the baryonic matter component [4, 6, 7]. Since the code reproduces the statistics...
Laurence Tresse Michel, Michel Dennefeld, Patrick Petitjean, Stefano Cristiani, Simon White
. We present spectroscopic observations of galaxies lying within 1 0 of QSO J2233--606 in the Hubble Deep Field South (HDF-S). Several are found to be coincident in redshift with absorption-line...
The metal line systems in HS1700+6416: Evidence for inhomogeneities (2007)
Patrick Petitjean Rudiger, Patrick Petitjean, Rudiger Riediger, Michael Rauch
. We present a high S/N ratio optical spectrum of the bright quasar HS 1700+6416. These data usefully complement the UV HST data from Vogel & Reimers (1995). We analyse the metal line systems...
In response to the comments by Murphy et al. (arxiv:0708.3677) (2007)
Srianand, Raghunathan, Chand, Hum, Petitjean, Patrick, Aracil, Bastien
In their comment, Murphy et al. (arxiv:0708.3677) criticize the fitting procedure we used in two previous papers [Srianand et al. 2004(Paper I) and Chand et al. 2004 (Paper II)] and conclude that the...
Line shift, line asymmetry, and the 6Li/7Li isotopic ratio determination (2007)
Cayrel, Roger, Steffen, Matthias, Chand, Hum, Bonifacio, Piercarlo, Spite, Monique, Spite, François, ...
Context: Line asymmetries are generated by convective Doppler shifts in stellar atmospheres, especially in metal-poor stars, where convective motions penetrate to higher atmospheric levels. Such...
Multiphase Plasma in Sub-Damped Lyman Alpha Systems: A Hidden Metal Reservoir (2007)
Fox, Andrew J, Petitjean, Patrick, Ledoux, Cédric, Srianand, Raghunathan
We present a VLT/UVES spectrum of a proximate sub-damped Lyman-alpha (sub-DLA) system at z=2.65618 toward the quasar Q0331-4505 (z_qso=2.6785+/-0.0030). Absorption lines of O I, Si II, Si III, Si IV,...
The World Federation of Scientific Workers (WFScW) and UNESCO have roots in the Social Relations of Science (SRS) movements and in the Franco-British scientific relations in the 1930s. These years...
Fox, Andrew J., Ledoux, Cédric, Petitjean, Patrick, Srianand, Raghunathan
We present a study of C IV absorption in a sample of 63 damped Lyman-alpha (DLA) systems and 11 sub-DLAs in the redshift range 1.75
Evidence for overdensity around z_em > 4 quasars from the proximity effect (2007)
Guimaraes, Rodney Nascimento, Petitjean, Patrick, Rollinde, Emmanuel Beaumont, De Carvalho, Reinaldo Ramos, Djorgovski, George, Srianand, R., ...
We study the density field around z_em > 4 quasars using high quality medium spectral resolution ESI-Keck spectra (R~4300, SNR > 25) of 45 high-redshift quasars selected from a total of 95 spectra....
Fox, Andrew J., Petitjean, Patrick, Ledoux, Cedric, Srianand, Raghunathan
(ABRIDGED) We present a study of the highly ionized gas (plasma) associated with damped Lyman-alpha (DLA) systems at z=2.1-3.1. We search for O VI absorption and corresponding Si IV, C IV, and N V in...
Before World War II, international science was mainly European and Eurocentric. The International Council of Scientific Unions and the International Institute for Intellectual Co-operation paid very...
Les enjeux sociaux des sciences : un enjeu essentiel dans l'histoire de l'Unesco (2007)
Les premiers scientifiques dirigeants de l'Unesco, Julian Huxley et Joseph Needham, sont issus des "mouvements pour les relations sociales de la science" qui se sont développés dans les années...
Evidence for overdensity around z_em > 4 quasars from the proximity effect. (2007)
Guimaraes, Rodney, Petitjean, Patrick, Rollinde, Emmanuel, De Carvalho, Reinaldo, Djorgovski, George, Srianand, R., ...
We study the density field around z_em > 4 quasars using high quality medium spectral resolution ESI-Keck spectra (R~4300, SNR > 25) of 45 high-redshift quasars selected from a total of 95 spectra....
1947-1950 : quand l'Unesco a cherché à se démarquer des histoires européocentristes (2007)
Petitjean, Patrick, Bertol Domingues, Heloisa Maria
En novembre 1947, lUnesco décide dengager lédition dune Histoire Scientifique et Culturelle de lHumanité «pour montrer la dépendance mutuelle des peuples et des cultures». Les...
En 1946, Joliot-Curie n'hésite pas à parler de "science franco-britannique". C'est la conséquence de relations étroites, construites dans la seconde moitié des années 1930, interrompues pas la...
Line shift, line asymmetry, and the 6Li/7Li isotopic ratio determination (2007)
Cayrel, Roger, Steffen, Matthias, Chand, Hum, Bonifacio, Piercarlo, Spite, Monique, Spite, François, ...
Context: Line asymmetries are generated by convective Doppler shifts in stellar atmospheres, especially in metal-poor stars, where convective motions penetrate to higher atmospheric levels. Such...
Les congrès internationaux d'histoire des sciences ont rarement été à l'abri des controverses politiques ou sociales, notamment dans les années 1930 et 1940. L'Académie internationale...
Les congrès internationaux d'histoire des sciences ont rarement été à l'abri des controverses politiques ou sociales, notamment dans les années 1930 et 1940. L'Académie internationale...
Les enjeux sociaux des sciences : un enjeu essentiel dans l'histoire de l'Unesco (2007)
Les premiers scientifiques dirigeants de l'Unesco, Julian Huxley et Joseph Needham, sont issus des "mouvements pour les relations sociales de la science" qui se sont développés dans les années...
Before World War II, international science was mainly European and Eurocentric. The International Council of Scientific Unions and the International Institute for Intellectual Co-operation paid very...
Line shift, line asymmetry, and the 6Li/7Li isotopic ratio determination (2007)
Cayrel, Roger, Steffen, Matthias, Chand, Hum, Bonifacio, Piercarlo, Spite, Monique, Spite, François, ...
Context: Line asymmetries are generated by convective Doppler shifts in stellar atmospheres, especially in metal-poor stars, where convective motions penetrate to higher atmospheric levels. Such...
En 1946, Joliot-Curie n'hésite pas à parler de "science franco-britannique". C'est la conséquence de relations étroites, construites dans la seconde moitié des années 1930, interrompues pas la...
1947-1950 : quand l'Unesco a cherché à se démarquer des histoires européocentristes (2007)
Petitjean, Patrick, Bertol Domingues, Heloisa Maria
En novembre 1947, lUnesco décide dengager lédition dune Histoire Scientifique et Culturelle de lHumanité «pour montrer la dépendance mutuelle des peuples et des cultures». Les...
Evidence for overdensity around z_em > 4 quasars from the proximity effect. (2007)
Guimaraes, Rodney, Petitjean, Patrick, Rollinde, Emmanuel, De Carvalho, Reinaldo, Djorgovski, George, Srianand, R., ...
We study the density field around z_em > 4 quasars using high quality medium spectral resolution ESI-Keck spectra (R~4300, SNR > 25) of 45 high-redshift quasars selected from a total of 95 spectra....
The WFScW and Unesco have roots in the Social Relations of Science movements of the 1930s. They were prepared through many wartime debates about the function to be played by science for the welfare...
Srianand, Raghunathan, Gupta, Neeraj, Petitjean, Patrick
We searched for 21-cm absorption associated with the z_abs = 1.3647 absorption system toward PKS 0237-233 using the GMRT. A high quality UVES spectrum shows that C I and C I* are detected at this...
J.G. Crowther and the Anglo-French Society of Sciences (2006)
During the 1930s British and French scientists developed sociabilities mixing professional relations with political or ideological affinities, social leanings and engagement against fascism. An...
Adaptive Optics imaging of Quasar Hosts (2006)
Adaptive Optics imaging of Quasar Hosts
Metallicity as a criterion to select H2 bearing Damped Lyman-alpha systems (2006)
Petitjean, Patrick, Ledoux, C., Noterdaeme, P., Srianand, R.
We characterize the importance of metallicity on the presence of molecular hydrogen in damped Lyman-alpha (DLA) systems. We construct a representative sample of 18 DLA/sub-DLA systems with log...
Chand, Hum, Srianand, Raghunathan, Petitjean, Patrick, Aracil, Bastien, Quast, Ralf, Reimers, Dieter
We present a detailed analysis of a very high resolution (R\approx 112,000) spectrum of the quasar HE 0515-4414 obtained using the High Accuracy Radial velocity Planet Searcher (HARPS) mounted on the...
Le contexte des années 1930 n'a pas permis aux scientifiques de rester en marge de la société, malgré le désir d'une partie d'entre eux, qui imaginait que son métier devait les conduire à se...
Darwinismo e o projeto da Unesco, do Instituto Internacional da Hiléia Amazônica (1946-1950) (2006)
Petitjean, Patrick, Bertol Domingues, Heloisa Maria
Em junho de 1946, na sua primeira reunião preparatória, em Londres, a Unesco aprovou a criação do Instituto Internacional da Hiléia Amazônica (IIHA), que tinha como objetivo desenvolver...
La science doit achever sa décolonisation (2006)
Dans la deuxième vague impériale après 1870, les scientifiques ont été des participants actifs de la colonisation et du parti colonial en France. La science a été un élément constitutif...
J.G. Crowther and the Anglo-French Society of Sciences (2006)
During the 1930s British and French scientists developed sociabilities mixing professional relations with political or ideological affinities, social leanings and engagement against fascism. An...
Defining UNESCOs scientific culture: 1945-1965 (2006)
When World War II was approaching towards its end, the Allied Countries redefined the international relations, among which scientific co-operation. Their aim was to take into account the new function...
Contributing to the Development of Science in Latin America (2006)
Needham applied the "periphery principle" in promoting the development of science beyond Europe. UNESCO organized its first regional scientific conference for Latin America in Montevideo (September...
Pierre Auger and the Founding of CERN (2006)
From the international scientific laboratories proposed, CERN (European Nuclear Organisation) was the only one that has been rapidly realized in the mid-1950s, and in conformity with the initial aim....
The Post-War International Laboratories Projects (2006)
One of the first initiatives taken by Laugier and Needham in May 1946 has been to propose the establishment of international scientific laboratories. Laugier had a centralized conception, and Needham...
The Sciences within the United Nations System (2006)
UNESCO has not been the only tool after the war for a refoundation of the international scientific relations. The United Nations built a complete system, keeping for its own the general orientations,...
Needham and UNESCO: perspectives and realizations (2006)
Joseph Needham, biochemist and historian of science, Marxist and Anglican, was the first head of the Natural Sciences Division in UNESCO, from April 1946 when he just returned from China. He spent...
The Birth of the Scientific and Cultural History of Mankind Project (2006)
Febvre, Needham and Huxley shared the paternity of the UNESCO's project to publish an Scientific and Cultural History of Mankind (SCHM). The project aimed to give a central part to the sciences and...
UNESCO and the International Union for History of Science (2006)
The International Academy for History of Science had many difficulties to survive after the war. It has been a very small, elitist, closed, and bureaucratic body. The importance given by Needham to...
The WFSW and Unesco in the late 1940s (2006)
The left-sided scientists, most of them being in fact British or French, established the World Federation of Scientific Workers (WFSW) in July 1946, when UNESCO was "a work in progress". UNESCO's...
The Early Yars of UNESCO-ICSU Partnership (2006)
The International Council of Scientific Unions (ICSU) suspended its activities during the war. One essential UNESCO's function, according to Needham, was to revive the ICSU and to help, through it,...
The World Federation of Scientific Workers (WFScW) and UNESCO have roots in the Social Relations of Science (SRS) movements and in the Franco-British scientific relations in the 1930s. These years...
The World Federation of Scientific Workers (WFScW) and UNESCO have roots in the Social Relations of Science (SRS) movements and in the Franco-British scientific relations in the 1930s. These years...
The Birth of the Scientific and Cultural History of Mankind Project (2006)
Febvre, Needham and Huxley shared the paternity of the UNESCO's project to publish an Scientific and Cultural History of Mankind (SCHM). The project aimed to give a central part to the sciences and...
UNESCO and the International Union for History of Science (2006)
The International Academy for History of Science had many difficulties to survive after the war. It has been a very small, elitist, closed, and bureaucratic body. The importance given by Needham to...
The WFSW and Unesco in the late 1940s (2006)
The left-sided scientists, most of them being in fact British or French, established the World Federation of Scientific Workers (WFSW) in July 1946, when UNESCO was "a work in progress". UNESCO's...
The Early Yars of UNESCO-ICSU Partnership (2006)
The International Council of Scientific Unions (ICSU) suspended its activities during the war. One essential UNESCO's function, according to Needham, was to revive the ICSU and to help, through it,...
Contributing to the Development of Science in Latin America (2006)
Needham applied the "periphery principle" in promoting the development of science beyond Europe. UNESCO organized its first regional scientific conference for Latin America in Montevideo (September...
Pierre Auger and the Founding of CERN (2006)
From the international scientific laboratories proposed, CERN (European Nuclear Organisation) was the only one that has been rapidly realized in the mid-1950s, and in conformity with the initial aim....
The Post-War International Laboratories Projects (2006)
One of the first initiatives taken by Laugier and Needham in May 1946 has been to propose the establishment of international scientific laboratories. Laugier had a centralized conception, and Needham...
The Sciences within the United Nations System (2006)
UNESCO has not been the only tool after the war for a refoundation of the international scientific relations. The United Nations built a complete system, keeping for its own the general orientations,...
Needham and UNESCO: perspectives and realizations (2006)
Joseph Needham, biochemist and historian of science, Marxist and Anglican, was the first head of the Natural Sciences Division in UNESCO, from April 1946 when he just returned from China. He spent...
Defining UNESCOs scientific culture: 1945-1965 (2006)
When World War II was approaching towards its end, the Allied Countries redefined the international relations, among which scientific co-operation. Their aim was to take into account the new function...
J.G. Crowther and the Anglo-French Society of Sciences (2006)
During the 1930s British and French scientists developed sociabilities mixing professional relations with political or ideological affinities, social leanings and engagement against fascism. An...
Darwinismo e o projeto da Unesco, do Instituto Internacional da Hiléia Amazônica (1946-1950) (2006)
Petitjean, Patrick, Bertol Domingues, Heloisa Maria
Em junho de 1946, na sua primeira reunião preparatória, em Londres, a Unesco aprovou a criação do Instituto Internacional da Hiléia Amazônica (IIHA), que tinha como objetivo desenvolver...
La science doit achever sa décolonisation (2006)
Dans la deuxième vague impériale après 1870, les scientifiques ont été des participants actifs de la colonisation et du parti colonial en France. La science a été un élément constitutif...
Le contexte des années 1930 n'a pas permis aux scientifiques de rester en marge de la société, malgré le désir d'une partie d'entre eux, qui imaginait que son métier devait les conduire à se...
Heinmueller, Janine, Petitjean, Patrick, Ledoux, Cedric, Caucci, Sara, Srianand, R.
We present UVES observations of the log N(HI)= 21.7 damped Lyman-alpha system at z=2.03954 towards the quasar PKS 0458-020. HI Lyman-alpha emission is detected in the center of the damped Lyman-alpha...
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...
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
Srianand, Raghunathan, Petitjean, Patrick, Ledoux, Cedric, Ferland, Gary, Shaw, Gargi
We study the physical conditions in DLAs, using a sample of 33 systems toward 26 QSOs acquired for a recently completed survey of H_2 by Ledoux et al. (2003). We use the column densities of H_2 in...
Molecular hydrogen in the diffuse interstellar medium at high redshift (2005)
Srianand, Raghunathan, Shaw, Gargi, Ferland, Gary, Petitjean, Patrick, Ledoux, Cedric
Physical conditions within DLAs can reveal the star formation history, determine the chemical composition of the associated ISM, and hence document the first steps in the formation of present day...
The second detection of CO at redshift larger than 4 (2005)
Guilloteau, Stephane, Omont, Alain, McMahon, Richard G., Cox, Pierre, Petitjean, Patrick
We report the detection with the IRAM interferometer at 3mm of J=5-4 CO line in the radio quiet quasar BRI1335-0415 at redshift of z=4.41. After BR1202-0725 at z=4.69 (Ohta etal 1996, Omont etal...
Molecular gas and dust around a radio-quiet quasar at redshift 4.7 (2005)
Omont, Alain, Petitjean, Patrick, Guilloteau, Stephane, McMahon, Richard G., Solomon, P. M., Pecontal, Emmanuel
We report the detection of emission from dust and carbon monoxide in the radio-quiet quasar BR1202--0725 at redshift z=4.7. Maps of these emissions reveal two objects separated by a few arc seconds,...
Science and the Civilizing Mission: France and the Colonial Enterprise (2005)
Which part was played by science in the French civilizing mission ? From the 1880s, the interests of science were combined with those of national prestige. Colonization was undertaken in the name...
Ecologia e Evolução: a Unesco na Amazônia (1946-1950) (2005)
Petitjean, Patrick, Bertol Domingues, Heloisa Maria
A proposta de criação do IIHA foi um dos primeiros projetos da Unesco, em 1946, e tinha como base teórica idéias evolucionistas darwinianas e como objetivo desenvolver pesquisas em ecologia. Seus...
Avant la fin de la deuxième guerre mondiale, les Alliés se préoccupent de la reconstruction des pays dévastés et de la remise sur pied d'institutions internationales. La place de la science est...
In November 1945 the foundation of Unesco took place in the very specific political and historical context of the immediate post-war period, before the cold war over-determined international...
Ecologia e Evolução: a Unesco na Amazônia (1946-1950) (2005)
Petitjean, Patrick, Bertol Domingues, Heloisa Maria
A proposta de criação do IIHA foi um dos primeiros projetos da Unesco, em 1946, e tinha como base teórica idéias evolucionistas darwinianas e como objetivo desenvolver pesquisas em ecologia. Seus...
Avant la fin de la deuxième guerre mondiale, les Alliés se préoccupent de la reconstruction des pays dévastés et de la remise sur pied d'institutions internationales. La place de la science est...
In November 1945 the foundation of Unesco took place in the very specific political and historical context of the immediate post-war period, before the cold war over-determined international...
Science and the Civilizing Mission: France and the Colonial Enterprise (2005)
Which part was played by science in the French civilizing mission ? From the 1880s, the interests of science were combined with those of national prestige. Colonization was undertaken in the name...
Chand, Hum, Petitjean, Patrick, Srianand, Raghunathan, Aracil, Bastien
We report a new constraint on the variation of the fine-structure constant based on the analysis of 15 Si IV doublets selected from a ESO-UVES sample. We find \Delta\alpha/\alpha = (+0.15+/-0.43) x...
Srianand, Raghunathan, Chand, Hum, Petitjean, Patrick, Aracil, Bastien
Most of the successful physical theories rely on the constancy of few fundamental quantities (such as the speed of light, $c$, the fine-structure constant, \alpha, the proton to electron mass ratio,...
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
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
International Science, Brazil and Diplomacy in Unesco (1946-1950) (2004)
Petitjean, Patrick, Bertol Domingues, Heloisa Maria
At the end of World War II, numerous initiatives for international scientific cooperation were undertaken by the UNO: the creation of a science division in Unesco, projects of international...
Paulo Carneiro: um cientista brasileiro na diplomacia da Unesco (1946-1950) (2004)
Petitjean, Patrick, Bertol Domingues, Heloisa Maria
Ao fim da guerra, a cooperação científica internacional era percebida como um compromisso político e econômico importante para os organismos internacionais a serem estruturados. A Unesco foi...
Paulo Carneiro: um cientista brasileiro na diplomacia da Unesco (1946-1950) (2004)
Petitjean, Patrick, Bertol Domingues, Heloisa Maria
Ao fim da guerra, a cooperação científica internacional era percebida como um compromisso político e econômico importante para os organismos internacionais a serem estruturados. A Unesco foi...
International Science, Brazil and Diplomacy in Unesco (1946-1950) (2004)
Petitjean, Patrick, Bertol Domingues, Heloisa Maria
At the end of World War II, numerous initiatives for international scientific cooperation were undertaken by the UNO: the creation of a science division in Unesco, projects of international...
CIV Absorbers in z>4 Quasars: Tracing Early Galactic Halos Evolution (2003)
Peroux, Celine, Petitjean, Patrick, Aracil, Bastien, Irwin, Mike, McMahon, Richard
We use 29 z>4 quasar spectra to build a homogeneous sample of high-redshift CIV absorbers. We use these data to calculate the number density, n(z), of W_rest(CIV)>0.30 A CIV doublets. We find that...
Ellison, Sara L., Ibata, Rodrigo, Pettini, Max, Lewis, Geraint F., Aracil, Bastien, Petitjean, Patrick, ...
We have obtained spatially resolved spectra of the z=3.911 triply imaged QSO APM08279+5255 using the Space Telescope Imaging Spectrograph (STIS) on board the Hubble Space Telescope (HST). We study...
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)...
The Structure of High Redshift Galactic Halos (2003)
Ellison, Sara L., Ibata, Rodrigo, Pettini, Max, Lewis, Geraint F., Aracil, Bastien, Petitjean, Patrick, ...
Observations of multiple or lensed QSOs at high redshift can be used to probe transverse structure in intervening absorption systems. Here we present results obtained from STIS spectroscopy of the...
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
Outflowing material in the zem = 4.92 BAL QSO SDSS~J160501.21-011220.0 (2003)
Gupta, Neeraj, Srianand, Raghunathan, Petitjean, Patrick, Ledoux, Cedric
We present the analysis of two BALs seen in the spectrum of the QSO SDSS J160501.21-011220.0. Our UVES spectrum shows two well detached BALs at z(abs)= 4.685 and 4.855. The system at z(abs)= 4.855...
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...
A new measurement of zinc metallicity in a DLA at z=3.35 (2002)
Peroux, Celine, Petitjean, Patrick, Aracil, Bastien, Srianand, R.
We present chemical abundance measurements in the z_abs=3.35045 Damped Lyman-alpha (DLA) system observed in the UVES spectrum of the BAL quasar BR 1117-1329. We measure a neutral hydrogen column...
The Abundances of Nitrogen and Oxygen in Damped Lyman Alpha Systems (2002)
Pettini, Max, Ellison, Sara L., Bergeron, Jacqueline, Petitjean, Patrick
We take a fresh look at the abundance of nitrogen in DLAs with oxygen abundances between 1/10 and 1/100 of solar. This is a metallicity regime poorly sampled in the local universe and where QSO...
Lewis, Geraint F., Ibata, Rodrigo A., Ellison, Sara L., Aracil, Bastien, Petitjean, Patrick, Pettini, Max, ...
While gravitationally lensed quasars are expected to display an odd number of images, invariably systems are observed with an even number of quasars. For this, lensing galaxies must have very small...
D'Odorico, Valentina, Petitjean, Patrick, Cristiani, Stefano
We study the transverse clustering properties of high matter density peaks as traced by high column density absorption systems (either Lyman limit systems characterized by N(HI)> 2 x 10^{17} cm^{-2}...
Petitjean, Patrick, Srianand, R., Ledoux, Cédric
We study the dust depletion pattern in eight well separated components of the z=1.973, logN(HI)=20.83, damped Lyman-alpha system toward Q0013-004, four of which have detectable H2 absorption. The...
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...
Coincidences of high density peaks in UVES spectra of QSO pairs (2001)
D'Odorico, Valentina, Petitjean, Patrick, Cristiani, Stefano
We present preliminary results of an investigation of the clustering properties of high matter density peaks between redshift ~2 and ~3, as traced by Lyman limit and Damped Ly-alpha systems in...
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...
D'Odorico, Valentina, Petitjean, Patrick
We present a detailed analysis of three metal absorption systems observed in the spectrum of the HDF-South quasar J2233-606 (z_em = 2.238), taking advantage of new VLT-UVES high resolution data...
L'histoire des intellectuels s'intéresse aux réseaux de sociabilité, avec comme objectif de dépasser à la fois une certaine tradition française de l'histoire "politique", et une ap-proche...
A Unesco, O Instituto Internacional da Hileia Amazonica e a antropologia no final dos anos 40 (2001)
Petitjean, Patrick, Bertol Domingues, Heloisa Maria
"A extensao e a gravidade desse desperecimento da terra, num processo irreversivel, despertou alarme mundial e, hoje, uma legiao de cientistas esta mobilizada numa campanha internacional pela...
A Unesco, O Instituto Internacional da Hileia Amazonica e a antropologia no final dos anos 40 (2001)
Petitjean, Patrick, Bertol Domingues, Heloisa Maria
"A extensao e a gravidade desse desperecimento da terra, num processo irreversivel, despertou alarme mundial e, hoje, uma legiao de cientistas esta mobilizada numa campanha internacional pela...
L'histoire des intellectuels s'intéresse aux réseaux de sociabilité, avec comme objectif de dépasser à la fois une certaine tradition française de l'histoire "politique", et une ap-proche...
The microwave background temperature at the redshift of 2.33771 (2000)
Srianand, R., Petitjean, Patrick, Ledoux, Cedric
The Cosmic Microwave Background radiation is a fundamental prediction of Hot Big Bang cosmology. The temperature of its black-body spectrum has been measured at the present time, $T_{\rm CMBR,0}$ =...
ATCA search for 21 cm emission from a candidate damped Ly-$\alpha$ absorber at z = 0.101 (2000)
Kanekar, Nissim, Chengalur, Jayaram N, Subrahmanyan, Ravi, Petitjean, Patrick
We report a deep search for 21 cm emission/absorption from the $z \sim 0.101$ candidate damped Lyman-$\alpha$ system towards PKS 0439-433, using the Australia Telescope Compact Array (ATCA). The...
Molecular hydrogen and the nature of damped Lyman-alpha systems (2000)
Petitjean, Patrick, Srianand, R., Ledoux, Cédric
We report results from our mini-survey for molecular hydrogen in eight high redshift damped Lyman-alpha (DLA) systems using the ESO Ultra-violet and Visible Spectrograph on the VLT. In addition, we...
Petitjean, Patrick, Aracil, Bastien, Srianand, R., Ibata, Rodrigo
A study of the absorption systems toward the gravitationally lensed quasar APM 08279+5255 is presented. Most of the MgII systems in the redshift range 1.2-2.07, although saturated, show large...
A Redescoberta da Amazonia num Projeto da Unesco (2000)
Petitjean, Patrick, Bertol Domingues, Heloisa Maria
Este trabalho trata de um dos primeiros projetos da Unesco, instituçao que foi criada no contexto de conciliaçao dos paises no imediato pos-segunda guerra. O IIHA foi analisado como uma...
A Redescoberta da Amazonia num Projeto da Unesco (2000)
Petitjean, Patrick, Bertol Domingues, Heloisa Maria
Este trabalho trata de um dos primeiros projetos da Unesco, instituçao que foi criada no contexto de conciliaçao dos paises no imediato pos-segunda guerra. O IIHA foi analisado como uma...
Petitjean, Patrick, Srianand, R.
Results of a careful analysis of the highly ionized absorption systems, observed over the redshift range 2.198--2.2215 in the zem=2.24 HDFS-QSO J2233-606, are presented. Strong OVI and NeVIII...
Needham, Anglo-French Civilities and Ecumenical Science (1999)
Which intellectual and institutional trajectory lead Needham to his international commitment? To elucidate some aspects of this question, the paper is mainly focalised upon Needham's specificity...
Needham, Anglo-French Civilities and Ecumenical Science (1999)
Which intellectual and institutional trajectory lead Needham to his international commitment? To elucidate some aspects of this question, the paper is mainly focalised upon Needham's specificity...
QSO Absorption Line Systems (1998)
It is difficult to describe in a few pages the numerous specific techniques used to study absorption lines seen in QSO spectra and to review even rapidly the field of research based on their...
Molecules in QSOs and QSO Absorption Line Systems at High Redshift (1998)
Molecules dominate the cooling function of neutral metal-poor gas at high density. Observation of molecules at high redshift is thus an important tool toward understanding the physical conditions...
HST Observations of the QSO pair Q1026-0045A,B (1998)
Petitjean, Patrick, Surdej, Jean, Smette, Alain, Shaver, Peter, Muecket, Jan, Remy, Marc
The spatial distribution of the Ly$\alpha$ forest is studied using new HST data for the quasar pair Q~1026--0045 A and B at $z_{em}$ = 1.438 and 1.520 respectively. The angular separation is 36...
Are Damped Lyman alpha Systems Rotating Disks ? (1998)
Ledoux, Cedric, Petitjean, Patrick, Bergeron, Jacqueline
We report on high spectral resolution observations of five damped Lyman alpha systems whose line velocity profiles and abundances are analyzed. By combining these data with information from the...
The second detection of CO at redshift larger than 4 (1997)
Guilloteau, Stephane, Omont, Alain, McMahon, Richard G., Cox, Pierre, Petitjean, Patrick
We report the detection with the IRAM interferometer at 3mm of J=5-4 CO line in the radio quiet quasar BRI1335-0415 at redshift of z=4.41. After BR1202-0725 at z=4.69 (Ohta etal 1996, Omont etal...
The second detection of CO at redshift larger than 4 (1997)
Guilloteau, Stephane, Omont, Alain, McMahon, Richard G., Cox, Pierre, Petitjean, Patrick
We report the detection with the IRAM interferometer at 3mm of J=5-4 CO line in the radio quiet quasar BRI1335-0415 at redshift of z=4.41. After BR1202-0725 at z=4.69 (Ohta etal 1996, Omont etal...
The second detection of CO at redshift larger than 4 (1997)
Guilloteau, Stephane, Omont, Alain, McMahon, Richard G., Cox, Pierre, Petitjean, Patrick
We report the detection with the IRAM interferometer at 3mm of J=5-4 CO line in the radio quiet quasar BRI1335-0415 at redshift of z=4.41. After BR1202-0725 at z=4.69 (Ohta etal 1996, Omont etal...
Evolution of the Lyman alpha forest from high to low redshift (1997)
Rüdiger Riediger, Patrick Petitjean
. We study the evolution with redshift, from z ¸ 5 to z = 0, of the Lymanff forest in a CDM model using numerical simulations including collisionless particles only. The baryonic component is...
Clustering of absorption line systems (1996)
Absorption line systems are luminosity unbiased tracers of the spatial distribution of baryons over most of the history of the Universe. I review the importance of studying the clustering properties...
Molecular gas and dust around a radio-quiet quasar at redshift 4.7 (1996)
Omont, Alain, Petitjean, Patrick, Guilloteau, Stephane, McMahon, Richard G., Solomon, P. M., Pecontal, Emmanuel
We report the detection of emission from dust and carbon monoxide in the radio-quiet quasar BR1202--0725 at redshift z=4.7. Maps of these emissions reveal two objects separated by a few arc seconds,...
A damped Ly-alpha candidate at z~0.1 toward Q 0439-433 (1996)
Petitjean, Patrick, Theodore, Bertrand, Smette, Alain, Lespine, Yannick
We report on the detection of a z_gal=0.101 galaxy projected on the sky at 4.2 arcsec (or 5.2 h^{-1} kpc for q_o=0.5) from the quasar Q 0439-433 (z_em=0.594). The HST spectrum of the quasar shows...
Lespine, Yannick, Petitjean, Patrick
We present a high spectral resolution optical spectrum of the bright quasar Q~1037-2704. The large number of absorption systems suggests the presence of an intervening supercluster, but the issue...
Molecular gas and dust around a radio-quiet quasar at redshift 4.7 (1996)
Omont, Alain, Petitjean, Patrick, Guilloteau, Stephane, McMahon, Richard G., Solomon, P. M., Pecontal, Emmanuel
We report the detection of emission from dust and carbon monoxide in the radio-quiet quasar BR1202--0725 at redshift z=4.7. Maps of these emissions reveal two objects separated by a few arc seconds,...
Molecular gas and dust around a radio-quiet quasar at redshift 4.7 (1996)
Omont, Alain, Petitjean, Patrick, Guilloteau, Stephane, McMahon, Richard G., Solomon, P. M., Pecontal, Emmanuel
We report the detection of emission from dust and carbon monoxide in the radio-quiet quasar BR1202--0725 at redshift z=4.7. Maps of these emissions reveal two objects separated by a few arc seconds,...
Evolution of the Ly$\alpha$ forest: a consistent picture (1995)
Mücket, Jan P., Petitjean, Patrick, Kates, Ronald E., Riediger, Rüdiger
We study the evolution with redshift of the number density of Ly$\alpha$ clouds in a CDM model using numerical simulations including photo-ionization and cooling of the baryonic component. The...
The metal line systems in HS1700+6416: Evidence for inhomogeneities (1995)
Petitjean, Patrick, Riediger, Ruediger, Rauch, Michael
We present a high S/N ratio optical spectrum of the bright quasar HS1700+6416. These data usefully complement the UV HST data from Vogel and Reimers (1995). We analyse the metal line systems using...
THE LYMAN-ALPHA FOREST AT LOW REDSHIFT: TRACING THE DARK MATTER FILAMENTS (1995)
Petitjean, Patrick, Mücket, Jan P., Kates, Ron
We study the distribution of low-redshift Ly$\alpha$ clouds in a CDM model using numerical simulations including photoionization and cooling of the baryonic component. The ionizing background is...
Evolution of the Ly alpha forest: a consistent picture (1995)
Jan P. Mücket, Patrick Petitjean, Ronald E. Kates, R Udiger Riediger
. We study the evolution with redshift of the number density of Lyff clouds in a CDM model using numerical simulations including photo-ionization and cooling of the baryonic component. The...
Petitjean, Patrick, Jami, Catherine, Moulin, Anne Marie
Incluye índice
Essai d'analyse système de la S.N.C.F. (Société nationale des chemins de fer français) / (1973)
Grandjean, Jean-Claude., Petitjean, Patrick., Sylvestre Baron, Patrick.
Mémoire DES : U.E.R. 20 / Paris II ; 1973 : sess. de fév.