Euro50: A European 50madaptive Optics Extremely Large Telescope

Ardeberg, A.; Andersen, Torben

doi:10.1007/1-4020-4526-3_22

Cited by 7 publications

(8 citation statements)

References 102 publications

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“…a Photometry is from Massey (2002) or Parker et al (1992) (preferred) or from Dachs (1970); Azzopardi et al (1975); Ardeberg & Maurice (1977); Isserstedt (1978); Ardeberg (1980); Bouchet et al (1985); Gordon et al (2003); Lennon et al (2003); and/or Evans et al (2006). b Using intrinsic colors of FitzGerald 1970 and assuming a Galactic contribution of 0.03-0.04 mag.…”

Section: Starmentioning

confidence: 99%

INTERSTELLAR H I AND H₂IN THE MAGELLANIC CLOUDS: AN EXPANDED SAMPLE BASED ON ULTRAVIOLET ABSORPTION-LINE DATA

Welty

Xue

Wong

2012

ApJ

179

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We have determined column densities of H I and/or H 2 for sight lines in the Magellanic Clouds from archival HST and FUSE spectra of H I Lyman-α and H 2 Lymanband absorption. Together with some similar data from the literature, we now have absorption-based N (H I) and/or N (H 2 ) for 285 LMC and SMC sight lines (114 with a detection or limit for both species) -enabling more extensive, direct, and accurate determinations of molecular fractions, gas-to-dust ratios, and elemental depletions in these two nearby, low-metallicity galaxies. For sight lines where the N (H I) estimated from 21 cm emission is significantly higher than the value derived from Lyman-α absorption (presumably due to emission from gas beyond the target stars), integration of the 21 cm profile only over the velocity range seen in Na I or H 2 absorption generally yields much better agreement. Conversely, N (21 cm) can be lower than N (Ly-α) by factors of 2-3 in some LMC sight lines -suggestive of small-scale structure within the 21 cm beam(s) and/or some saturation in the emission. The mean gas-to-dust ratios obtained from N (H tot )/E(B − V ) are larger than in our Galaxy, by factors of 2.8-2.9 in the LMC and 4.1-5.2 in the SMC -i.e., factors similar to the differences in metallicity. The N (H 2 )/E(B − V ) ratios are more similar in the three galaxies, but with considerable scatter within each galaxy. These data may be used to test models of the atomic-to-molecular transition at low metallicities and predictions of N (H 2 ) based on comparisons of 21 cm emission and the IR emission from dust. a Entries marked with an asterisk include contributions from another weak, isolated component. b Column density integrated over full extent of 21 cm profile. c Column density integrated over limited range in velocities seen in Na I absorption (extended by 5 km s −1 at both ends).

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Section: Starmentioning

confidence: 99%

INTERSTELLAR H I AND H₂IN THE MAGELLANIC CLOUDS: AN EXPANDED SAMPLE BASED ON ULTRAVIOLET ABSORPTION-LINE DATA

Welty

Xue

Wong

2012

ApJ

179

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“…Both runs employed set-ups similar to those used in previous highresolution surveys of K I, Ca I and Ca II (Welty, Morton & Hobbs 1996;Welty, Hobbs & Morton 2003;) -with camera 6, grism 780-2 and the 3 • wedge for cross-dispersion, and BG3+CuSO 4 filters to isolate the spectral region from about 3270 to 3490 Å. The set-ups used a very narrow slit, corresponding to about 0.65 arcsec on the sky, to achieve resolutions of 1.3-1.5 km s −1 (similar to the values achieved in the previous high-resolution surveys), as determined from the widths of the thorium lines in the Dachs (1970), Azzopardi, Vigneau & Macquet (1975), Ardeberg & Maurice (1977), Bouchet et al (1985), and/or Gordon et al (2003). E(B − V ) is calculated using the intrinsic colours of FitzGerald (1970) Bouchet & Martin (1989), Evans et al (2004) and/or Welty & Crowther (in preparation); values with a colon are less well determined.…”

Section: Kpno Coudé Feedmentioning

confidence: 99%

Interstellar Ti ii in the Milky Way and Magellanic Clouds

Welty

Crowther

2010

Monthly Notices of the Royal Astronomical Society

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We discuss several sets of Ti ii absorption‐line data, which probe a variety of interstellar environments in our Galaxy and in the Magellanic Clouds. Comparisons of high‐resolution [full width at half‐maximum (FWHM) ∼ 1.3–1.5 km s−1] Ti ii spectra of Galactic targets with corresponding high‐resolution spectra of Na i, K i and Ca ii reveal both similarities and differences in the detailed structure of the absorption‐line profiles – reflecting component‐to‐component differences in the ionization and depletion behaviour of those species. Moderate‐resolution (FWHM ∼ 3.4–4.5 km s−1) spectra of more heavily reddened Galactic stars provide more extensive information on the titanium depletion in colder, denser clouds – where more than 99.9 per cent of the Ti may be in the dust phase. Moderate‐resolution (FWHM ∼ 4.5–8.7 km s−1) spectra of stars in the Magellanic Clouds suggest that the titanium depletion is generally much less severe in the Large and Small Magellanic Clouds than in our Galaxy [for a given N(Htot), E(B−V), or molecular fraction f(H2)]– providing additional evidence for differences in depletion patterns in those two lower‐metallicity galaxies. We briefly discuss possible implications of these results for the interpretation of gas‐phase abundances in quasi‐stellar object absorption‐line systems and of variations in the D/H ratio in the local Galactic interstellar medium.

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“…For a Jupiter-Saturn binary system with the same separation the exo-Jupiter velocity is 10 km s −1 . The feasibility of this wobble approach has been addressed in the context of Extremely Large Telescopes by Ardeberg (2005).…”

Section: Planet Wobblementioning

confidence: 99%

Detecting companions to extrasolar planets using mutual events

Cabrera¹

2007

A&A

100

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Aims. We investigate a new approach to the detection of companions to extrasolar planets beyond the transit method. We discuss the possibility of the existence of "binary planets". Methods. We develop a method based on the imaging of a planet-companion as an unresolved system (but resolved from its parent star). It makes use of planet-companion "mutual phenomena", namely mutual transits and mutual shadows. Results. We show that companions can be detected and their radius measured down to lunar sizes.

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Euro50: A European 50madaptive Optics Extremely Large Telescope

Cited by 7 publications

References 102 publications

INTERSTELLAR H I AND H₂IN THE MAGELLANIC CLOUDS: AN EXPANDED SAMPLE BASED ON ULTRAVIOLET ABSORPTION-LINE DATA

INTERSTELLAR H I AND H₂IN THE MAGELLANIC CLOUDS: AN EXPANDED SAMPLE BASED ON ULTRAVIOLET ABSORPTION-LINE DATA

Interstellar Ti ii in the Milky Way and Magellanic Clouds

Detecting companions to extrasolar planets using mutual events

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Euro50: A European 50madaptive Optics Extremely Large Telescope

Cited by 7 publications

References 102 publications

INTERSTELLAR H I AND H2IN THE MAGELLANIC CLOUDS: AN EXPANDED SAMPLE BASED ON ULTRAVIOLET ABSORPTION-LINE DATA

INTERSTELLAR H I AND H2IN THE MAGELLANIC CLOUDS: AN EXPANDED SAMPLE BASED ON ULTRAVIOLET ABSORPTION-LINE DATA

Interstellar Ti ii in the Milky Way and Magellanic Clouds

Detecting companions to extrasolar planets using mutual events

Contact Info

Product

Resources

About

INTERSTELLAR H I AND H₂IN THE MAGELLANIC CLOUDS: AN EXPANDED SAMPLE BASED ON ULTRAVIOLET ABSORPTION-LINE DATA

INTERSTELLAR H I AND H₂IN THE MAGELLANIC CLOUDS: AN EXPANDED SAMPLE BASED ON ULTRAVIOLET ABSORPTION-LINE DATA