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Tohoku-Hiroshima-Nagoya planetary spectra library: a method for characterizing planets in the visible to near infrared
Context: A comprehensive framework for comparing spectral data fromdifferent planets has yet to be established. This framework is neededfor the study of extrasolar planets and objects within the solarsystem. Aims: We completed observations to compile a libraryof planet spectra for all planets, some moons, and some dwarf planets inthe solar system to study their general spectroscopic and photometricnatures. Methods: During May and November of 2008, weacquired spectra for the planets using TRISPEC, which is capable ofsimultaneous three-band spectroscopy across a wide wavelength range of0.45-2.5 ?m with low resolving power (?/?? ~140-360). Results: Patterns emerge when comparing thespectra. By analyzing their general spectroscopic and photometricnatures, we show that it is possible to distinguish between gas planets,soil planets, and ice planets. These methods can be applied toextrasolar observations acquired using low resolution spectrography orbroad-band filters. Conclusions: The present planet spectrallibrary is the first library to contain observational spectra for all ofthe solar system planets, based on simultaneous observations at visibleand near infrared wavelengths. This library will be a useful referencefor analyzing extrasolar planet spectra and calibrating planetary datasets.THN Planet spectra library is only available in electronic form at theCDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/507/1649
| Intermediate-Brightness Equatorial Spectrophotometric Standards
We have obtained spectral energy distributions for 41 7m 8m stars nearthe celestial equator (δ=±3°). The λλ31007600 Å spectral range is studied with a spectral resolution of 50Å. The relative rms error in the visible is 1 2%, increasing to 35% towards the edges of the wavelength interval studied. All stars arereferenced to a single standard, the circumpolar star HD 221525. Thesynthetic colors of common stars are compared with those observed infour photometric systems: U BV, W BV R, uvby, and that of the TYCHOcatalog. The program stars are recommended as secondaryspectrophotometric standards.
| A spectroscopic survey for lambda Bootis stars. II. The observational data
lambda Bootis stars comprise only a small number of all A-type stars andare characterized as nonmagnetic, Population i, late B to early F-typedwarfs which show significant underabundances of metals whereas thelight elements (C, N, O and S) are almost normal abundant compared tothe Sun. In the second paper on a spectroscopic survey for lambda Bootisstars, we present the spectral classifications of all program starsobserved. These stars were selected on the basis of their Strömgrenuvbybeta colors as lambda Bootis candidates. In total, 708 objects insix open clusters, the Orion OB1 association and the Galactic field wereclassified. In addition, 9 serendipity non-candidates in the vicinity ofour program stars as well as 15 Guide Star Catalogue stars were observedresulting in a total of 732 classified stars. The 15 objects from theGuide Star Catalogue are part of a program for the classification ofapparent variable stars from the Fine Guidance Sensors of the HubbleSpace Telescope. A grid of 105 MK standard as well as ``pathological''stars guarantees a precise classification. A comparison of our spectralclassification with the extensive work of Abt & Morrell(\cite{Abt95}) shows no significant differences. The derived types are0.23 +/- 0.09 (rms error per measurement) subclasses later and 0.30 +/-0.08 luminosity classes more luminous than those of Abt & Morrell(\cite{Abt95}) based on a sample of 160 objects in common. The estimatederrors of the means are +/- 0.1 subclasses. The characteristics of oursample are discussed in respect to the distribution on the sky, apparentvisual magnitudes and Strömgren uvbybeta colors. Based onobservations from the Observatoire de Haute-Provence, OsservatorioAstronomico di Padova-Asiago, Observatório do Pico dosDias-LNA/CNPq/MCT, Chews Ridge Observatory (MIRA) and University ofToronto Southern Observatory (Las Campanas).
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Besorolás csoportokba:
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Pozíciós és asztrometriai adatok
| Csillagkép: | Halak |
| Rektaszcenzió: | 22h51m33.43s |
| Deklináció: | -01°48'46.4" |
| Vizuális fényesség: | 8.168 |
| Távolság: | 237.53 parszek |
| RA sajátmozgás: | -4.8 |
| Dec sajátmozgás: | -6.7 |
| B-T magnitude: | 8.359 |
| V-T magnitude: | 8.184 |
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