J/A+A/462/795 Echelle spectra of 10 bright asteroids (Zwitter+, 2007)
Asteroids as radial velocity and resolving power standards for medium and
high resolution spectroscopy.
Zwitter T., Mignard F., Crifo F.
<Astron. Astrophys. 462, 795 (2007)>
=2007A&A...462..795Z 2007A&A...462..795Z
ADC_Keywords: Minor planets ; Spectroscopy
Keywords: techniques: radial velocities - techniques: spectroscopic -
instrumentation: spectrographs - minor planets, asteroids -
Sun: photosphere
Abstract:
Echelle spectra of 10 bright asteroids are presented and compared
against an observed twilight spectrum and a computed Solar spectrum.
Spectra covering a 2130Å spectral range centered on 5785Å are of
high resolving power and high signal to noise ratio. We compare
detailed properties of spectral lines and not albedo variations. It is
shown that the normalized Solar and asteroid spectra are identical
except for radial velocity (RV) shifts which can be predicted at
accuracy level of 1m/s. So asteroids are proposed as new and
extremely accurate radial velocity standards. Predicted and measured
RVs of observed asteroids match within the limits of accuracy of the
instrument. There are numerous absorption lines in the reflected Solar
spectrum. This allows a direct mapping of the resolving power of a
spectrograph between and along echelle spectral orders. Thus asteroid
spectra can be used to test the wavelength calibration and resolving
power of spectrographs on the ground as well as in space, including
the Gaia mission of ESA.
Description:
Table 5 gives observed spectra of twilight and asteroids rebinned to
the same wavelength bins, continuum normalized and Doppler shifted to
zero radial velocity. Asteroid spectra of 1 Ceres, 2 Pallas, 3 Juno, 4
Vesta, 9 Metis, 21 Lutetia, 27 Euterpe, 40 Harmonia, 49 Pales, and 80
Sappho are given. Spectra of observed twilight sky and of a
theoretical Kurucz Solar model are added for comparison.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table5.dat 88 13665 Spectra
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See also:
B/astorb : Orbits of Minor Planets and Comets (Bowell+ 2006)
Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 9 F9.4 0.1nm lambda Wavelength
11- 15 F5.3 --- twil Twilight flux
17- 21 F5.3 --- medaster Median asteroid flux
23- 27 F5.3 --- kurucz Kurucz Solar model flux
29- 33 F5.3 --- Ceres01 Flux of 1 Ceres
35- 39 F5.3 --- Pallas02 Flux of 2 Pallas
41- 45 F5.3 --- Juno03 Flux of 3 Juno
47- 51 F5.3 --- Vesta04 Flux of 4 Vesta
53- 57 F5.3 --- Metis09 Flux of 9 Metis
59- 64 F6.3 --- Lutetia21 Flux of 21 Lutetia
66- 70 F5.3 --- Euterpe27 Flux of 27 Euterpe
72- 76 F5.3 --- Harmonia40 Flux of 40 Harmonia
78- 82 F5.3 --- Pales49 Flux of 59 Pales
84- 88 F5.3 --- Sappho80 Flux of 80 Sappho
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Acknowledgements:
Tomaz Zwitter, tomaz.zwitter(at)fmf.uni-lj.si
(End) Tomaz Zwitter [Ljubljana Univ., Slovenia], P. Vannier [CDS] 09-Oct-2006