On the HU Aquarii planetary system hypothesis

Abstract

In this work, we investigate the eclipse timing of the polar binary HU Aquarii that has been ob-served for almost two decades. Recently, Qian et al. attributed large (O-C) deviations between the eclipse ephemeris and observations to a compact system of two massive jovian compan-ions. We improve the Keplerian, kinematic model of the Light Travel Time (LTT) effect and re-analyse the whole currently available data set. We add almost 60 new, yet unpublished, mostly precision light curves obtained using the time high-resolution photo-polarimeter OP-TIMA, as well as photometric observations performed at the MONET/N, PIRATE and TCS telescopes. We determine new mid–egress times with a mean uncertainty at the level of 1 sec-ond or better. We claim that because the observations that currently exist in the literature are non-homogeneous with respect to spectral windows (ultraviolet, X-ray, visual, polarimetric