Dharmawardena, TE, Kemper, F, Srinivasan, S, Scicluna, P, Marshall, JP, Wouterloot, JGA, Greaves, J, Goldman, SR, van Loon, JT, Matsuura, M, McDonald, I, He, J, Zijlstra, AA, Toalá, JA, Wallström, SHJ, Kim, H, Trejo, A, Ventura, P, Lagadec, E, Boyer, ML, Liu, T, Rau, G, Izumiura, H, Cami, J, Holland, W, Jones, O and Shinnaga, H (2019) The nearby evolved stars survey – I. JCMT/SCUBA-2 submillimetre detection of the detached shell of U Antliae. Monthly Notices of the Royal Astronomical Society, 489 (3). 3218 -3231.

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We present the highest resolution single-dish submillimetre observations of the detached shell source U Antliae to date. The observations were obtained at $450$ and $850\,μ\rm m$ with SCUBA-2 instrument on the James Clerk Maxwell Telescope as part of the Nearby Evolved Stars Survey. The emission at $850\,μ\rm m$ peaks at 40 arcsec with hints of a second peak seen at ∼20 arcsec. The emission can be traced out to a radius of 56 arcsec at a 3σ level. The outer peak observed at $850\,μ\rm m$ aligns well with the peak observed at Herschel/PACS wavelengths. With the help of spectral energy distribution fitting and radiative transfer calculations of multiple-shell models for the circumstellar envelope, we explore the various shell structures and the variation of grain sizes along the in the circumstellar envelope. We determine a total shell dust mass of (2.0 ± 0.3) × 10−5 M⊙ and established that the thermal pulse that gave rise to the detached shell occurred 3500 ± 500 yr ago.