A DEBRIS disk around the planet hosting M-star GJ 581 spatially resolved with Herschel

摘要: Debris disks have been found primarily around intermediate and solar mass stars (spectral types A-K) but rarely low M-type stars. We spatially resolved a debris disk the remarkable M3-type star GJ 581 hosting multiple planets using deep PACS images at 70, 100 160µm as part of DEBRIS Program on Herschel Space Observatory . This is second an star, after one surrounding young AU Mic (12 Myr). However, much older (2-8 Gyr), X-ray quiet in ROSAT data. fi t axisymmetric model to three that best fit for extending radially f rom 25± 12 more than 60 AU. Such cold reminiscent Kuiper Belt it surrounds (0.3 M⊙) its fractional dust luminosity Ldust/L∗ of∼ 10 −4 higher. The inclination limits our analysis make masses small enough ensure long-term stability system according some dynamical simulations. collisionally dominated down submicron-sized grains cannot be expelled from by radiation or wind pressures because 581. suggest correlation between low-mass recently G-type also applies Finally, known planets, orbiting within 0.3 dynamically perturb over age suggesting additional plane exists larger distance stirring reple nish dust.