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Abstract: Abridged The Edgeworth-Kuiper belt with its presumed dusty debris is anatural reference for extrsolar debris disks. We employ a new algorithm toeliminate the inclination and the distance selection effects in the known TNOpopulations to derive expected parameters of the -true- EKB. Its estimated massis M EKB=0.12 M earth, which is by a factor of \sim 15 larger than the mass ofthe EKB objects detected so far. About a half of the total EKB mass is inclassical and resonant objects and another half is in scattered ones. Treatingthe debiased populations of EKB objects as dust parent bodies, we then-generate- their dust disk with our collisional code. Apart from accuratehandling of collisions and direct radiation pressure, we include thePoynting-Robertson P-R drag, which cannot be ignored for the EKB dust disk.Outside the classical EKB, the radial profile of the optical depthapproximately follows tau \sim r^-2 which is roughly intermediate between theslope predicted analytically for collision-dominated r^-1.5 andtransport-dominated r^-2.5 disks. The cross section-dominating grain sizestill lies just above the blowout size \sim 1

.2 \microm, as it wouldwithout the P-R transport. However, if the EKB were by one order of magnitudeless massive, the optical depth profile would fall off as tau \sim r^-3, andthe cross section-dominating grain size would shift from \sim 1

.2\microm to~100 \microm. These properties are seen if dust is assumed to be generated onlyby known TNOs. If the solar system were observed from outside, the thermalemission flux from the EKB dust would be about two orders of magnitude lowerthan for solar-type stars with the brightest known infrared excesses observedfrom the same distance. Herschel and other new-generation facilities shouldreveal extrasolar debris disks nearly as tenuous as the EKB disk. TheHerschel-PACS instrument should be able to detect disks at a \sim 1

.2M EKBlevel.



Autor: Christian Vitense, Alexander V. Krivov, Torsten Löhne

Fuente: https://arxiv.org/







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