We report an analysis of the dust disk around DM~Tau, newly observed with the Atacama Large Millimeter/submillimeter Array (ALMA) at 1.3 mm. The ALMA observations with high sensitivity (8.4~μJy/beam) and high angular resolution (35~mas, 5.1~au) detect two asymmetries on the ring at r∼20~au. They could be two vortices in early evolution, the destruction of a large scale vortex, or double continuum emission peaks with different dust sizes. We also found millimeter emissions with ∼50~μJy (a lower limit dust mass of 0.3~MMoon) inside the 3-au ring. To characterize these emissions, we modeled the spectral energy distribution (SED) of DM~Tau using a Monte Carlo radiative transfer code. We found that an additional ring at r= 1~au could explain both the DM~Tau SED and the central point source. The disk midplane temperature at the 1-au ring calculated in our modeling is less than the typical water sublimation temperature of 150~K, prompting the possibility of forming small icy planets there.
@article{arxiv.2102.05905,
title = {ALMA Observations of the Asymmetric Dust Disk around DM Tau},
author = {Jun Hashimoto and Takayuki Muto and Ruobing Dong and Hauyu Baobab Liu and Nienke van der Marel and Logan Francis and Yasuhiro Hasegawa and Takashi Tsukagoshi},
journal= {arXiv preprint arXiv:2102.05905},
year = {2021}
}