Spectral properties of nine M-type asteroids

Free access article

Issue		A&A Volume 475, Number 2, November IV 2007


Page(s)		747 - 754
Section		Planets and planetary systems
DOI		http://dx.doi.org/10.1051/0004-6361:20077914

A&A 475, 747-754 (2007)
DOI: 10.1051/0004-6361:20077914

Spectral properties of nine M-type asteroids

M. Birlan¹, P. Vernazza², and D. A. Nedelcu^{1, 3}

¹ Institut de Mécanique Céleste et de Calcul des Éphémérides (IMCCE), Observatoire de Paris, 77 avenue Denfert-Rochereau, 75014 Paris Cedex, France
    e-mail: Mirel.Birlan@imcce.fr
² LESIA, Observatoire de Paris-Meudon, 5 place Jules Janssen, 92195 Meudon Cedex, France
    e-mail: Pierre.Vernazza@obspm.fr
³ Astronomical Institute of the Romanian Academy, 5 Cu titul de Argint, 75212 Bucharest, Romania
    e-mail: nedelcu@imcce.fr

(Received 19 May 2007 / Accepted 27 August 2007)

Abstract
Aims. We present spectroscopic results for nine M-type asteroids (325 Heidelberga, 497 Iva, 558 Carmen, 687 Tinette, 766 Moguntia, 860 Ursina, 909 Ulla, 1280 Baillauda, and 1564 Srbija) in the 0.8-2.5 $\mu$ m spectral region. One visible spectrum is also presented for the asteroid 497 Iva. These asteroids were observed during several runs between 2003 and 2007, and the main goal was to investigate the NIR spectral region of M-type asteroids.
Methods. The data was obtained with SpeX/IRTF in Prism mode and Dolores/TNG in LR-B mode. Spectral analysis was performed by comparing the M-type spectra and the meteorite ones ( $\chi^2$ approach) and the Modified Gaussian Model.
Results. With one exception, the asteroids present positive slopes of the spectra, with no absorption features, in good agreement with the spectra of metallic meteorites. The analysis of the asteroid 766 Moguntia was done by means of $\chi^2$ , MGM techniques, and the Shkuratov scattering law. We conclude that the mineralogy is dominated by olivine. Its NIR spectrum is similar to those of CO/CV meteorites.

Key words: minor planets, asteroids

What is OpenURL?

The OpenURL standard is a protocol for transmission of metadata describing the resource that you wish to access. An OpenURL link contains article metadata and directs it to the OpenURL server of your choice. The OpenURL server can provide access to the resource and also offer complementary services (specific search engine, export of references...). The OpenURL link can be generated by different means.

If your librarian has set up your subscription with an OpenURL resolver, OpenURL links appear automatically on the abstract pages.
You can define your own OpenURL resolver with your EDPS Account. In this case your choice will be given priority over that of your library.
You can use an add-on for your browser (Firefox or I.E.) to display OpenURL links on a page (see http://www.openly.com/openurlref/). You should disable this module if you wish to use the OpenURL server that you or your library have defined.