Polarimetric survey of main-belt asteroids III. Results for 33 X-type objects

CAÑADA ASSANDRI, M.; GIL-HUTTON, R.

ASTRONOMY AND ASTROPHYSICS

EDP SCIENCES S A

Lugar: Paris; Año: 2012 vol. 542 p. 1 - 5

0004-6361

Aims. We present results of a polarimetric survey of main-belt asteroids at Complejo Astronómico El Leoncito (Casleo), San Juan,Argentina. The aims of this survey are to increase the database of asteroid polarimetry, to estimate diversity in polarimetric propertiesof asteroids that belong to different taxonomic classes, and to search for objects that exhibit anomalous polarimetric properties.Methods. The data were obtained with the Torino and CASPROF polarimeters at the 2.15 m telescope. The Torino polarimeter isan instrument that allows the simultaneous measurement of polarization in five different bands, and the CASPROF polarimeter is atwo-hole aperture polarimeter with rapid modulation.Results. The survey began in 2003, and up to 2009 data of a sample of more than 170 asteroids were obtained. In this paper the resultsfor 33 X-type objects are presented, several of them are being polarimetrically observed for the first time. Using these data we foundpolarization curves and polarimetric parameters for different groups among this taxonomic class and that there are objects with verydifferent albedo in the sub-classes of the X taxonomic complex.