Some supernovae (SNe) show evidence for mass-loss events taking place prior to their explosions. Measuring their pre-outburst mass-loss rates provides essential information regarding the mechanisms that are responsible for these events. Here we present XMM-Newton and Swift X-ray observations taken after the latest, and presumably the final, outburst of SN?2009ip. We use these observations as well as new near-infrared and visible-light spectra and published radio and visible-light observations to put six independent order-of-magnitude constraints on the mass-loss rate of the SN progenitor prior to the explosion. Our methods utilize the X-ray luminosity, the bound-free absorption, the Hα luminosity, the SN rise time, free-free absorption, and the bolometric luminosity of the outburst detected prior to the explosion. Assuming spherical mass loss with a wind-density profile, we estimate that the effective mass-loss rate from the progenitor was between 10–3 and 10–2?M ☉?yr–1, over a few years prior to the explosion, with a velocity of ~103?km?s–1. This mass-loss rate corresponds to a total circumstellar matter (CSM) mass of ~0.04?M ☉, within 6 × 1015?cm of the SN. We note that the mass-loss rate estimate based on the Hα luminosity is higher by an order of magnitude. This can be explained if the narrow-line Hα component is generated at radii larger than the shock radius, or if the CSM has an aspherical geometry. We discuss simple geometries which are consistent with our results.
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