We present deep 1.2 millimeter photometry of 37 stars in the young (5 Myr) Upper Scorpius OB association, sensitive to ~4 x 10^-3 Mjup of cool millimeter dust. Disks around four low- and solar-mass stars are detected, as well as one debris disk around an intermediate mass star, with dust masses ranging from 3.6 x 10^-3 -- 1.0 x 10^-1 Mjup. The source with the most massive disk exhibits a transition-disk spectral energy distribution. Combining our results with previous studies, we find the millimeter-detection fraction of Class II sources has significantly decreased from younger ages, and comparison with near-infrared and Halpha measurements indicates the present disks have undergone significant evolution in composition or structure at all radii. The disks of Upper Scorpius represent the tail-end of the depletion of primordial disks; while a few near-solar mass stars may still sustain giant planet formation, this process has finished around higher mass stars
@article{arxiv.1111.0101,
title = {The Late Stages of Protoplanetary Disk Evolution: A Millimeter Survey of Upper Scorpius},
author = {Geoffrey S. Mathews and Jonathan P. Williams and Francois Ménard and Neil Phillips and Gaspard Duchêne and Christophe Pinte},
journal= {arXiv preprint arXiv:1111.0101},
year = {2015}
}