R. Ferlet | Centre National de la Recherche Scientifique / French National Centre for Scientific Research (original) (raw)
Papers by R. Ferlet
Arxiv preprint astro-ph/9905162, 1999
Oxford Bibliographies Online Datasets
Astronomy and Astrophysics
GHRS high resolution spectra of {beta \:Pictoris} were obtained to study the stable gas around th... more GHRS high resolution spectra of {beta \:Pictoris} were obtained to study the stable gas around this star. Several elements are detected and their abundances measured. Upper limits to the abundances of others are also measured. The data permit improved chemical analysis of the stable gas around {beta \:Pictoris}, and yield new and more accurate estimates of the radiation pressure acting on various elements. We first analyze the data in the framework of a closed-box model. The electron density is evaluated (Neion {S}imeq10(6) cm(-3) ), which in turn implies constraints on the ionization stages of the various elements. The refractory elements in the stable gas have then standard abundances. In contrast, in this model, the lighter elements sulfur and carbon, observed in their neutral form, seem to be depleted. However several arguments, especially the strong radiation pressure, argue against a closed-box hypothesis. We therefore develop hydrodynamical simulations, taking into account th...
L'étude des lignes de visée de ε et beta CMa nous a permis non seulement de détecter pour la ... more L'étude des lignes de visée de ε et beta CMa nous a permis non seulement de détecter pour la première fois l'interface entre le gaz coronal qui remplit la bulle locale et les nuages diffus, mais aussi de mettre en évidence l'existence de nuages diffus très ionisés, ou encore de confirmer la très faible quantité de matière présente vers ε
Astronomy and …, 1994
Lagrange-Henri et al. 1989, Paper VIII; Grady et al. 1991; Bruh-late heavy bombardment ofthe Moon... more Lagrange-Henri et al. 1989, Paper VIII; Grady et al. 1991; Bruh-late heavy bombardment ofthe Moon lasted until7 108 ye&s afweiler et al. 1991; Deleuil et al. 1993, Paper XV), and more ter the Solar System formed. Moreover, the breakup ofone large
Science, 1996
Candidate pre-main-sequence stars were observed in the bar of the Large Magellanic Cloud during t... more Candidate pre-main-sequence stars were observed in the bar of the Large Magellanic Cloud during the search for dark matter in the galactic halo. Seven blue stars of apparent visual magnitude 15 to 17 had irregular photometric variations and hydrogen emission lines in their optical spectra, which suggested that these stars are pre-main-sequence stars of about 10 solar masses. These stars are slightly more massive and definitely more luminous than are Herbig AeBe pre-main-sequence stars in our own galaxy. Continued observations of these very young stars from another galaxy, which are probably at the pre-hydrogen-burning stage, should provide important clues about early stages of star formation.
Planetary and Space Science, 1998
Arxiv preprint astro-ph/ …, 1995
arXiv (Cornell University), Feb 8, 2012
Molecular hydrogen (H2) is by far the most abundant material from which stars, protoplanetary dis... more Molecular hydrogen (H2) is by far the most abundant material from which stars, protoplanetary disks and giant planets form, but it is dif®cult to detect directly. Infrared emission lines from H2 have recently been reported towards b Pictoris, a star harbouring a young planetary system. This star is surrounded by a dusty `debris disk' that is continuously replenished either by collisions between asteroidal objects or by evaporation of ices on Chironlike objects. A gaseous disk has also been inferred from absorption lines in the stellar spectrum. Here we present the farultraviolet spectrum of b Pictoris, in which H2 absorption lines are not seen. This allows us to set a very low upper limit on the column density of H2: N(H2) # 10 18 cm. This non-detection is puzzling when compared to the quantity of H2 inferred from the infrared observations, but it does show that H2 is not in the disk on the direct line of sight. Carbon monoxide (CO) has been seen in absorption against the star, ...
Astrophysics and Space Science Library, 1997
We briefly present the gravitational microlensing phenomenon and the different on-going surveys. ... more We briefly present the gravitational microlensing phenomenon and the different on-going surveys. We then discuss its application to search for extrasolar planets.
Spectral distribution of the effective height h of the Earth atmosphere as observed with the SOPH... more Spectral distribution of the effective height h of the Earth atmosphere as observed with the SOPHIE instrument on the 193cm telescope at the Observatoire de Haute-Provence during the 16 August 2008 Lunar eclipse. These evaluations are made at about 2Å and 0.02Å spectral resolution. (4 data files).
tel.archives-ouvertes.fr
... KR, Hébrard, G., Moos, HW, & Knauth, DC 2003, ApJ, 586, 1094 Horne, K. 1986, PASP, 98, 60... more ... KR, Hébrard, G., Moos, HW, & Knauth, DC 2003, ApJ, 586, 1094 Horne, K. 1986, PASP, 98, 609 Humphreys, RM 1978, ApJS, 38, 309 Jenkins, EB, Tripp, TM ... 2002, ApJS, 140, 3 Morbidelli, L., Patriarchi, P., Perinotto, M., Barbaro, G., & di Bartolomeo, A. 1997, A&A, 327, 125 ...
The Astrophysical Journal, 2000
The Astrophysical Journal, 1985
... 298 V®(Na I) N(HI + H N(Na Star E(B-V) (pc) (km s 1) (1020 cm (1011 cm + 14 +13 bi +7.5 bl + ... more ... 298 V®(Na I) N(HI + H N(Na Star E(B-V) (pc) (km s 1) (1020 cm (1011 cm + 14 +13 bi +7.5 bl + 19 > 120. ... 2, 1985 Na i IN THE DIFFUSE ISM TABLE 1-Continued E(B-V) V®(Na I) (km s ') N(H i + HN(Na (1020 cm (101 1 cm + 8 - 10 -11 bl -08 bl > 76. ...
Arxiv preprint astro-ph/9905162, 1999
Oxford Bibliographies Online Datasets
Astronomy and Astrophysics
GHRS high resolution spectra of {beta \:Pictoris} were obtained to study the stable gas around th... more GHRS high resolution spectra of {beta \:Pictoris} were obtained to study the stable gas around this star. Several elements are detected and their abundances measured. Upper limits to the abundances of others are also measured. The data permit improved chemical analysis of the stable gas around {beta \:Pictoris}, and yield new and more accurate estimates of the radiation pressure acting on various elements. We first analyze the data in the framework of a closed-box model. The electron density is evaluated (Neion {S}imeq10(6) cm(-3) ), which in turn implies constraints on the ionization stages of the various elements. The refractory elements in the stable gas have then standard abundances. In contrast, in this model, the lighter elements sulfur and carbon, observed in their neutral form, seem to be depleted. However several arguments, especially the strong radiation pressure, argue against a closed-box hypothesis. We therefore develop hydrodynamical simulations, taking into account th...
L'étude des lignes de visée de ε et beta CMa nous a permis non seulement de détecter pour la ... more L'étude des lignes de visée de ε et beta CMa nous a permis non seulement de détecter pour la première fois l'interface entre le gaz coronal qui remplit la bulle locale et les nuages diffus, mais aussi de mettre en évidence l'existence de nuages diffus très ionisés, ou encore de confirmer la très faible quantité de matière présente vers ε
Astronomy and …, 1994
Lagrange-Henri et al. 1989, Paper VIII; Grady et al. 1991; Bruh-late heavy bombardment ofthe Moon... more Lagrange-Henri et al. 1989, Paper VIII; Grady et al. 1991; Bruh-late heavy bombardment ofthe Moon lasted until7 108 ye&s afweiler et al. 1991; Deleuil et al. 1993, Paper XV), and more ter the Solar System formed. Moreover, the breakup ofone large
Science, 1996
Candidate pre-main-sequence stars were observed in the bar of the Large Magellanic Cloud during t... more Candidate pre-main-sequence stars were observed in the bar of the Large Magellanic Cloud during the search for dark matter in the galactic halo. Seven blue stars of apparent visual magnitude 15 to 17 had irregular photometric variations and hydrogen emission lines in their optical spectra, which suggested that these stars are pre-main-sequence stars of about 10 solar masses. These stars are slightly more massive and definitely more luminous than are Herbig AeBe pre-main-sequence stars in our own galaxy. Continued observations of these very young stars from another galaxy, which are probably at the pre-hydrogen-burning stage, should provide important clues about early stages of star formation.
Planetary and Space Science, 1998
Arxiv preprint astro-ph/ …, 1995
arXiv (Cornell University), Feb 8, 2012
Molecular hydrogen (H2) is by far the most abundant material from which stars, protoplanetary dis... more Molecular hydrogen (H2) is by far the most abundant material from which stars, protoplanetary disks and giant planets form, but it is dif®cult to detect directly. Infrared emission lines from H2 have recently been reported towards b Pictoris, a star harbouring a young planetary system. This star is surrounded by a dusty `debris disk' that is continuously replenished either by collisions between asteroidal objects or by evaporation of ices on Chironlike objects. A gaseous disk has also been inferred from absorption lines in the stellar spectrum. Here we present the farultraviolet spectrum of b Pictoris, in which H2 absorption lines are not seen. This allows us to set a very low upper limit on the column density of H2: N(H2) # 10 18 cm. This non-detection is puzzling when compared to the quantity of H2 inferred from the infrared observations, but it does show that H2 is not in the disk on the direct line of sight. Carbon monoxide (CO) has been seen in absorption against the star, ...
Astrophysics and Space Science Library, 1997
We briefly present the gravitational microlensing phenomenon and the different on-going surveys. ... more We briefly present the gravitational microlensing phenomenon and the different on-going surveys. We then discuss its application to search for extrasolar planets.
Spectral distribution of the effective height h of the Earth atmosphere as observed with the SOPH... more Spectral distribution of the effective height h of the Earth atmosphere as observed with the SOPHIE instrument on the 193cm telescope at the Observatoire de Haute-Provence during the 16 August 2008 Lunar eclipse. These evaluations are made at about 2Å and 0.02Å spectral resolution. (4 data files).
tel.archives-ouvertes.fr
... KR, Hébrard, G., Moos, HW, & Knauth, DC 2003, ApJ, 586, 1094 Horne, K. 1986, PASP, 98, 60... more ... KR, Hébrard, G., Moos, HW, & Knauth, DC 2003, ApJ, 586, 1094 Horne, K. 1986, PASP, 98, 609 Humphreys, RM 1978, ApJS, 38, 309 Jenkins, EB, Tripp, TM ... 2002, ApJS, 140, 3 Morbidelli, L., Patriarchi, P., Perinotto, M., Barbaro, G., & di Bartolomeo, A. 1997, A&A, 327, 125 ...
The Astrophysical Journal, 2000
The Astrophysical Journal, 1985
... 298 V®(Na I) N(HI + H N(Na Star E(B-V) (pc) (km s 1) (1020 cm (1011 cm + 14 +13 bi +7.5 bl + ... more ... 298 V®(Na I) N(HI + H N(Na Star E(B-V) (pc) (km s 1) (1020 cm (1011 cm + 14 +13 bi +7.5 bl + 19 > 120. ... 2, 1985 Na i IN THE DIFFUSE ISM TABLE 1-Continued E(B-V) V®(Na I) (km s ') N(H i + HN(Na (1020 cm (101 1 cm + 8 - 10 -11 bl -08 bl > 76. ...