New dwarf galaxy candidates in the sphere of influence of the Local Volume spiral galaxy NGC2683

Abstract

We present initial results of a survey of host L∗ galaxies environments in the Local Volume (D\< 10\, Mpc) searching for satellite dwarf galaxy candidates using the wide-field Hyper Suprime-Cam imager on the 8 m Subaru Telescope. This paper presents complete results on NGC2683 (M B T,0=-19.62, D=9.36, Mpc, v⊙ =411, km s-1), an isolated Sc spiral galaxy in the Leo Spur. At the distance of NGC2683, we image the complete volume out to projected radii of 380 kpc using a hexagonal arrangement of 7 pointings. Direct inspection of the images is complete down to Mg ∼-11 and has revealed four new satellite galaxy candidates, two of which have been independently discovered by other researchers. Assuming the distance of NGC2683, these candidates span luminosities -12 < Mg < -9 and effective radii 150 pc <re < 1100 pc and are found to be morphologically reminiscent of satellite galaxies in the Local Group. These four new candidates add to the eight already known. A principle component analysis of the 2D projected distribution of the 12 satellite galaxies of NGC2683 reveals a flattened projected disc of satellites, with axis ratio b/a = 0.23. This flattening in the 2D projected system of satellites is a 1 per cent outlier of simulated isotropic satellite systems but is mostly consistent with satellite distributions of comparable galaxy environments in the IllustrisTNG simulation. This indicates the possible presence of a satellite plane, which will need to be investigated with follow-up observations.