Academic Thesis

Basic information

Name Watanabe Makoto
Belonging department Physics
Occupation name
researchmap researcher code B000222325
researchmap agency Okayama University of Science

Title

Study of hydrated asteroids via their polarimetric properties at low phase angles

Bibliography Type

Joint Author

Author

Jooyeon Geem, Masateru Ishiguro, Hiroyuki Naito, Sunao Hasegawa, Jun Takahashi, Yoonsoo P. Bach, Sunho Jin, Seiko Takagi, Tatsuharu Ono, Daisuke Kuroda, Tomohiko Sekiguchi, Kiyoshi Kuramoto, Tomoki Nakamura, Makoto Watanabe

Summary

Context. Ch-type asteroids are distinctive among other dark asteroids in that they exhibit deep negative polarization branches (NPBs). Nevertheless, the physical and compositional properties that cause their polarimetric distinctiveness are less investigated.

Aims. We aim to investigate the polarimetric uniqueness of Ch-type asteroids by making databases of various observational quantities (i.e., spectroscopic and photometric properties as well as polarimetric ones) of dark asteroids.

Methods. We conducted an intensive polarimetric survey of 52 dark asteroids (including 31 Ch-type asteroids) in the RC band to increase the size of polarimetric samples. The observed data were compiled with previous polarimetric, spectroscopic, and photometric archival data to find their correlations.

Results. We find remarkable correlations between these observed quantities, particularly the depth of NPBs and their spectroscopic features associated with the hydrated minerals. The amplitude of the opposition effect in photometric properties also shows correlations with polarimetric and spectral properties. However, these observed quantities do not show noticeable correlations with the geometric albedo, thermal inertia, and diameter of asteroids.

Conclusions. Based on the observational evidence, we arrive at our conclusion that the submicrometer-sized structures (fibrous or flaky puff pastry-like structures in phyllosilicates) in the regolith particles could contribute to the distinctive NPBs of hydrated asteroids.

Magazine(name)

Astronomy & Astrophysics

Publisher

EDP Sciences

Volume

688

Number Of Pages

StartingPage

A195

EndingPage

Date of Issue

2024/08

Referee

Exist

Invited

Not exist

Language

English

Thesis Type

Research papers (academic journals)

ISSN

DOI

10.1051/0004-6361/202450384

NAID

PMID

URL

J-GLOBAL ID

arXiv ID

ORCID Put Code

DBLP ID