Study of photometric phase curve with new brightness model: refining phase function system parameters of asteroid (107) Camilla

Abstract

We characterize the morphology of the photometric phase curve model of an asteroid with a three-parameter magnitude phase function H — G1 — G2 system by considering the effect of brightness variation arising from a triaxial ellipsoid representing the asteroid's shape. Applying this new model and a Markov Chain Monte Carlo method, we refine the photometric phase curve of asteroid (107) Camilla and obtain its absolute magnitude H = 7.026−0.054+0.052 mag, and phase function parameters G1 = 0.489−0.044+0.043 and G2 = 0.259−0.023+0.023. Meanwhile, we also determine (107) Camilla's orientation of pole (74.1°−4.5°+4.3°, 50.2°−5.0°+5.4°) with rotational period of 4.843928−0.00001+0.000001 h, and axial ratios a/b = 1.409−0.020+0.020 and b/c = 1.249−0.060+0.063. Furthermore, according to the values of phase function parameters G1 and G2, we infer that asteroid (107) Camilla is an X-type asteroid.