Systematic determination of dust properties for a sample of 133 spatially resolved debris discs

ABSTRACT Determination of the composition and size distribution of dust grains in debris discs is strongly dependent on constraining the underlying spatial distribution of that dust through multiwavelength, spatially resolved imaging spanning near-infrared to millimetre wavelengths. To date, spatially resolved imaging exists for well over a hundred debris disc systems. Simple analytical radiative transfer models of debris dust emission can reveal trends in disc properties as a function of their host stars’ luminosities. Here, we present such an analysis for 133 debris discs, calculating the dust grain minimum sizes ($s_{\rm min}$), dust masses ($M_{\rm dust}$), and exponents of the size distribution (q) in conjunction with their architectures determined at far-infrared or millimetre wavelengths. The distribution of q at far-infrared to millimetre wavelengths is characterized, finding a value of $3.49^{+0.38}_{-0.33}$. We further newly identify a trend between q and $R_{\rm disc}$, which may be indicative of velocity dependent fragmentation, or grain growth at large radii. We find the disc masses inferred from this analysis are consistent with those of protoplanetary discs. Finally, we identify samples of debris discs suitable for further characterization at millimetre and centimetre wavelengths, expanding the number of spatially resolved systems upon which future studies of these statistics can be based.