| Name: BIKI PRASAD |
| Affiliation: Assam University, Silchar |
| Conference ID: ASI2026_624 |
| Title: Polarimetric Properties of Main-Belt and Near-Earth Asteroids: A Comparative Study |
| Abstract Type: Oral |
| Abstract Category: Sun, Solar System, Exoplanets, and Astrobiology |
| Author(s) and Co-Author(s) with Affiliation: Biki Prasad(Department of Physics, Assam University, Silchar-788011, India), Himadri Sekhar Das(Department of Physics, Assam University, Silchar-788011, India) |
| Abstract: Polarimetric observations are an effective tool for investigating the surface scattering properties of asteroids through their phase–polarization curves. However, such studies are often limited to restricted phase-angle ranges because of observational constraints. In this work, we present a comparative polarimetric study of main-belt asteroids and near-Earth asteroids by combining new observations with published data to examine similarities and differences in their polarimetric properties across complementary phase-angle domains. We present R-band polarimetric observations of four main-belt asteroids: 13 Egeria, 4 Vesta, 10 Hygiea and 511 Davida, covering the low-phase-angle region of their phase-polarization curves, including the negative polarization branch and the inversion region. The observations of the four main-belt asteroids provide improved constraints on the negative polarization branch, inversion angle, and polarimetric slope, allowing a uniform characterization of their low-phase-angle polarimetric behavior across different compositional types. In contrast, we analyze polarimetric data of six near-Earth asteroids observed at phase angles extending up to ~140°, enabling characterization of the positive polarization branch and the maximum polarization. Using a common empirical phase–polarization model, key polarimetric parameters are derived for both main-belt and near-Earth asteroids and directly compared. The combined analysis reveals that the overall phase-polarization behavior of near-Earth asteroids is consistent with that of main-belt asteroids, taking into account differences in albedo and taxonomic class. This demonstrates that a unified analysis across complementary phase-angle domains plays a crucial role in reliably characterizing the full phase-polarization behavior of asteroids. |
