A catalog of near-IR absolute magnitudes of Solar System small bodies

TL;DR

This paper presents the first catalog of near-infrared absolute magnitudes for over 10,000 Solar System small bodies, using Bayesian methods to compare linear and non-linear phase curve models, revealing a phase-coloring effect.

Contribution

It provides the first near-infrared magnitude catalog for small bodies and evaluates the applicability of linear versus non-linear phase curve models using Bayesian inference.

Findings

Linear models accurately fit near-infrared phase curves.

A phase-coloring effect is detected in the near-infrared.

Fitting over larger phase angles (>9.5 deg) remains reliable.

Abstract

Context. Phase curves of small bodies are useful tools to obtain their absolute magnitudes and phase coefficients. The former relates to the object's apparent brightness, while the latter relates to how the light interacts with the surface. Data from multi-wavelength photometric surveys, which usually serendipitously observe small bodies, are becoming the cornerstone of large statistical studies of the Solar System. Nevertheless, to our knowledge, all studies have been carried out in visible wavelengths. Aims. We aim to provide the first catalog of absolute magnitudes in near-infrared filters (Y, J, H, and K). We will study the applicability of a non-linear model to these data and compare it with a simple linear model. Methods. We compute the absolute magnitudes using two photometric models: the HG* 12 and the linear model. We employ a combination of Bayesian inference and Monte Carlo sampling to calculate the probability distributions of the absolute magnitudes and their corresponding phase coefficients. We use the combination of four near-infrared photometric catalogs to create our input database. Results. We produced the first catalog of near-infrared magnitudes. We obtained absolute magnitudes for over 10 000 objects (with at least one absolute magnitude measured), with about 180 objects having four absolute magnitudes. We confirmed that a linear model that fits the phase curves produces accurate results. Since a linear behavior well describes the curves, fitting to a restricted phase angle range (in particular, larger than 9.5 deg) does not substantially affect the results. Finally, we also detect a phase-coloring effect in the near-infrared, as observed in visible wavelengths for asteroids and trans-Neptunian objects.