Tripathi, AnjaliAndrews, Sean M.Birnstiel, TilmanChandler, Claire J.Isella, AndreaPérez, Laura M.Harris, R.J.Ricci, LucaWilner, David J.Carpenter, John M.Calvet, N.Corder, S.A.Deller, A.T.Dullemond, C.P.Greaves, J.S.Henning, Th.Kwon, W.Lazio, J.Linz, H.Testi, L.2018-11-012018-11-012018Tripathi, Anjali, Andrews, Sean M., Birnstiel, Tilman, et al.. "The Millimeter Continuum Size–Frequency Relationship in the UZ Tau E Disk." <i>The Astrophysical Journal,</i> 861, (2018) IOP: https://doi.org/10.3847/1538-4357/aac5d6.https://hdl.handle.net/1911/103269We present high spatial resolution observations of the continuum emission from the young multiple star system UZ Tau at frequencies from 6 to 340 GHz. To quantify the spatial variation of dust emission in the UZ Tau E circumbinary disk, the observed interferometric visibilities are modeled with a simple parametric prescription for the radial surface brightnesses at each frequency. We find evidence that the spectrum steepens with radius in the disk, manifested as a positive correlation between the observing frequency and the radius that encircles a fixed fraction of the emission (R eff ∝ ν 0.34±0.08). The origins of this size–frequency relation are explored in the context of a theoretical framework for the growth and migration of disk solids. While that framework can reproduce a similar size–frequency relation, it predicts a steeper spectrum than that observed. Moreover, it comes closest to matching the data only on timescales much shorter (≤1 Myr) than the putative UZ Tau age (~2–3 Myr). These discrepancies are direct consequences of the rapid radial drift rates predicted by models of dust evolution in a smooth gas disk. One way to mitigate that efficiency problem is to invoke small-scale gas pressure modulations that locally concentrate drifting solids. If such particle traps reach high-continuum optical depths at 30–340 GHz with a ~30%–60% filling fraction in the inner disk (r lesssim 20 au), they can also explain the observed spatial gradient in the UZ Tau E disk spectrum.engArticle is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use.Journal articleTripathi_2018https://doi.org/10.3847/1538-4357/aac5d6