Maser mapping and dust properties of red supergiant winds

A.M.S. Richards, R.J. Cohen, J.A. Yates

Research output: Contribution to journalArticlepeer-review


Maser emission from the circumstellar envelopes of four late-type red supergiants has been mapped with milli-arcsecond resolution using MERLIN1. The wind is driven by radiation pressure on dust and the structure and kinematics of the masing regions reflect the dust properties. The unbeamed radius of water maser blobs, ~ 1012 m, has been measured for the first time. The velocity gradient is used to derive the dust absorption coefficient which increases with radius from ≤ 0.1 to ≤ 1.0 m2 kg−1. Comparison with laboratory studies suggests that small crystalline grains are formed near the star and are annealed into astronomical silicates at larger distances.
Original languageUndefined
Pages (from-to)55-62
Number of pages8
JournalAstrophysics and Space Science
Issue number1-2
Publication statusPublished - 1997


  • Radiation pressure
  • Maser emission
  • Circumstellar envelope
  • Clump size
  • Dust property

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