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arXiv · 1601.06835

The Debris Disk Fraction for M-dwarfs in Nearby, Young, Moving Groups

Alex Binks
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Abstract

I present the first substantial work to measure the fraction of debris disks for M-dwarfs in nearby moving groups (MGs). Utilising the $AllWISE$ IR catalog, 17 out of 151 MG members are found with an IR photometric excess indicative of disk structure. The M-dwarf debris disk fraction is $\lesssim 6$ per cent in MGs younger than 40\,Myr, and none are found in the groups older than 40\,Myr. Simulations show, however, that debris disks around M-dwarfs are not present above a $WISE$ $W1-W4$ colour of $\sim 2.5$, making calculating the absolute disk fractions difficult. The debris disk dissipation timescale appears to be faster than for higher-mass stars, and mechanisms such as enhanced stellar wind drag and/or photoevaporation could account for the more rapid decline of disks observed amongst M-dwarfs.

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Alex Binks. 2016-01-25. The Debris Disk Fraction for M-dwarfs in Nearby, Young, Moving Groups. https://doi.org/10.1017/s1743921315006158

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