Polarimetric survey of Phaethon with PICO

DOI

As a function of the solar phase angle, {alpha}, the linear polarization degree (referred to the scattering plane, P_r_) of solar system objects is a good diagnostic for understanding the scattering properties of their surface materials. We report the P_r_ of Phaethon over a wide range of {alpha} from 19.1{deg} to 114.3{deg}. The derived phase-polarization curve shows that the maximum of P_r_, Pmax, is >42.4% at {alpha}>114.3{deg}, a value significantly larger than those of the moderate albedo asteroids (Pmax~9%). The phase-polarization curve classifies Phaethon as B-type as well as M- and K-type asteroids, in the polarimetric taxonomy, being compatible with the spectral property. We compute the geometric albedo, p_v_, of 0.14+/-0.04 independently by using an empirical slope-albedo relation, and the derived p_v_ is consistent with previous results determined from mid-infrared spectra and thermophysical modeling. We find no periodic variation of P_r_ in our polarimetric data in the range from 0 up to 7.208hr (e.g., less than twice the rotational period). We also find significant differences between our P_r_ during the 2017 approach toward Earth and that in 2016, implying that Phaethon has a region with different properties for light scattering near its rotational pole.

Identifier
DOI http://doi.org/10.26093/cds/vizier.18649033
Source https://dc.g-vo.org/rr/q/lp/custom/CDS.VizieR/J/ApJ/864/L33
Related Identifier https://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/864/L33
Related Identifier http://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/864/L33
Metadata Access http://dc.g-vo.org/rr/q/pmh/pubreg.xml?verb=GetRecord&metadataPrefix=oai_b2find&identifier=ivo://CDS.VizieR/J/ApJ/864/L33
Provenance
Creator Shinnaka Y.; Kasuga T.; Furusho R.; Boice D.C.; Terai T.; Noda H.,Namiki N.; Watanabe J.-I.
Publisher CDS
Publication Year 2019
Rights https://cds.unistra.fr/vizier-org/licences_vizier.html
OpenAccess true
Contact CDS support team <cds-question(at)unistra.fr>
Representation
Resource Type Dataset; AstroObjects
Discipline Astrophysics and Astronomy; Exoplanet Astronomy; Natural Sciences; Observational Astronomy; Physics; Solar System Astronomy