Dynamical zodiacal cloud models constrained by high resolution spectroscopy of the zodiacal light

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.icarus.2007.11.009 Byline: Sergei I. Ipatov (a)(b), Alexander S. Kutyrev (c), Greg J. Madsen (d), John C. Mather (c), S. Harvey Moseley (c), Ronald J. Reynolds (e) Keywords: Asteroids; Comets; dust; Trans-neptunian objects; Spectroscopy; Zodiacal light Abstract: The simulated Doppler shifts of the solar Mg I Fraunhofer line produced by scattering on the solar light by asteroidal, cometary, and trans-neptunian dust particles are compared with the shifts obtained by Wisconsin H-Alpha Mapper (WHAM) spectrometer. The simulated spectra are based on the results of integrations of the orbital evolution of particles under the gravitational influence of planets, the Poynting-Robertson drag, radiation pressure, and solar wind drag. Our results demonstrate that the differences in the line centroid position in the solar elongation and in the line width averaged over the elongations for different sizes of particles are usually less than those for different sources of dust. The deviation of the derived spectral parameters for various sources of dust used in the model reached maximum at the elongation (measured eastward from the Sun) between 90[degrees] and 120[degrees]. For the future zodiacal light Doppler shifts measurements, it is important to pay a particular attention to observing at this elongation range. At the elongations of the fields observed by WHAM, the model-predicted Doppler shifts were close to each other for several scattering functions considered. Therefore the main conclusions of our paper do not depend on a scattering function and mass distribution of particles if they are reasonable. A comparison of the dependencies of the Doppler shifts on solar elongation and the mean width of the Mg I line modeled for different sources of dust with those obtained from the WHAM observations shows that the fraction of cometary particles in zodiacal dust is significant and can be dominant. Cometary particles originating inside Jupiter's orbit and particles originating beyond Jupiter's orbit (including trans-neptunian dust particles) can contribute to zodiacal dust about 1/3 each, with a possible deviation from 1/3 up to 0.1-0.2. The fraction of asteroidal dust is estimated to be [approximately equal to]0.3-0.5. The mean eccentricities of zodiacal particles located at 1-2 AU from the Sun that better fit the WHAM observations are between 0.2 and 0.5, with a more probable value of about 0.3. Author Affiliation: (a) Department of Terrestrial Magnetism of Carnegie Institution of Washington, 5241 Broad Branch Road, Washington, DC 20015-1305, USA (b) Space Research Institute, 84/32 Profsoyuznaya st., Moscow 117997, Russia (c) NASA/GSFC, Greenbelt, MD 20771, USA (d) Anglo-Australian Observatory, P.O. Box 296, Epping, NSW 1710, Australia (e) Department of Astronomy, University of Wisconsin at Madison, 475 North Charter St., Madison, WI 53706, USA Article History: Received 22 March 2007; Revised 2 November 2007