Asteroid absolute magnitudes and phase curve parameters from <i>Gaia</i> photometry

Aims. We perform light curve inversion for 491 asteroids to retrieve phase parameters, rotation periods, pole longitudes and latitudes, convex triaxial ellipsoid shapes by using the sparse photometric observations from Gaia Data Release 2 dense ground-based DAMIT database. develop a method derivation of reference absolute magnitudes curves data, allowing comparative studies involving hundreds asteroids. Methods. For both general shapes, we computed least-squares solutions either Levenberg-Marquardt optimization algorithm or Nelder-Mead downhill simplex method. Virtual were generated adding Gaussian random errors observations, and, later on, Markov chain Monte Carlo was applied sample spin, shape, scattering parameters. Absolute magnitude retrieval developed geometry equatorial illumination based on model averaged over rotational phase. Results. The derived slope values showed wide variations within each assumed Tholen class. G -band matched notably well with V retrieved Jet Propulsion Laboratory Small-Body Database. Finally, fitted H , 1 function. resulting distribution differed, in an intriguing way, that is corresponding brightness maxima.