Abstract :
[en] In this work we present a characterization of the dust environment of various Short Period Comets, with the purpose to improve the knowledge on their physical properties. Among this comet family members, we focused over 30P/Reinmuth 1, 78P/Gehrels 2, 123P/West-Hartley and P/2011 W2 (Rinner). We analyze CCD imaging observations during the last three years in Sierra Nevada Observatory (OSN), and perform a Monte Carlo dust tail analysis in order to retrieve the dust environment that best fits the observations. The dust parameters that we obtain are the mass lost rate, ejection terminal velocities, size distributions, and ejection morphology. In addition, we derive from the models the Afρ curves as a function of the heliocentric distance and compare them with the ones provided by the astronomical association Cometas-Obs during the passage of these objects at dates close to perihelion. Three of the comets studied, 78P, 123P, and Rinner, can be accurately fitted by an isotropic ejection model. However, for 30P, an anisotropic ejection model is required, with active areas on the surface located between latitudes -30° to +30°. From our study we derive that 78P/Gehrels 2 is the most active comet at perihelion, with a dust production rate of Qd= 550 kg/s, larger than the average of this comet family. The others three targets show a moderate dust loss rate.
