Tootfinder

SCOTCH III: Complete search for Hypercompact HII regions in the fourth quadrant
A. L. Patel (Kent), J. S. Urquhart (Kent), A. Y. Yang (NAOC, Key Laboratory of Radio Astronomy and Technology, Chinese Academy of Sciences), L. K. Morgan (GBT), K. M. Menten (LJMU), M. A. Thompson (MPIfR), T. Moore (Leeds), I. Grozdanova (Kent), S. Khan (LJMU), T. Csengeri (Univ. Bordeaux)

SCOTCH III: Complete search for Hypercompact HII regions in the fourth quadrant
We present high-frequency (18-24 GHz) radio continuum observations towards 335 methanol masers, excellent signposts for young, embedded high-mass protostars. These complete the search for hypercompact HII (HCHII) regions towards young high-mass star-forming clumps within the fourth quadrant of the Galactic plane. HCHII regions are the earliest observable signatures of radio continuum emission from high-mass stars ionizing their surroundings, though their rarity and short lifetimes make them cha…