Centimeter-sized Grains in the Compact Dust Ring around Very Low Mass Star CIDA 1

TL;DR

This study used JVLA observations to analyze the dust ring around the low-mass star CIDA 1, revealing centimeter-sized grains that indicate advanced grain growth and potential for planet formation.

Contribution

First direct measurement of centimeter-sized dust grains in the ring around a very low mass star, advancing understanding of early planet formation processes.

Findings

Detected partial-ring structures at centimeter wavelengths.

Estimated maximum grain size of approximately 2.5 cm.

Indicated significant grain growth facilitating planet formation.

Abstract

We examined the grain size in the dust ring encircling the 0.19~$M_\sun$ T Tauri star CIDA 1 using the Karl G. Jansky Very Large Array (JVLA) at multiple centimeter wavelengths, with a spatial resolution of 0$\farcs$2--0$\farcs$9. We detected distinct partial-ring structures at these wavelengths around CIDA~1. Based on spatial distributions and spectral indexes, we determined that these centimeter emissions originated from dust, rather than free-free or synchrotron emissions. To estimate the maximum grain size ($a_{\rm max}$) within the ring, we compared the observed spectral energy distribution (SED) with SEDs calculated for different $a_{\rm max}$ values using radiative transfer calculations. Our findings indicate an $a_{\rm max}$ value of approximately 2.5~cm in the ring, assuming the dust opacity can be approximated by the DSHARP models. These results suggest that grain growth took place within the CIDA~1 ring, potentially facilitating more efficient planet formation through pebble accretion scenarios involving centimeter-sized pebbles.