Young Stellar Objects Embedded in Ultracompact HII Regions

• Grant number: 09/07385-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: June 01, 2009
• End date: December 31, 2009
• Field of knowledge: Physical Sciences and Mathematics - Astronomy - Stellar Astrophysics
• Principal Investigator: Cássio Leandro Dal Ri Barbosa
• Grantee: Milton Vinícius Diogo de Sousa
• Host Institution: Instituto de Pesquisa e Desenvolvimento (IP&D). Universidade do Vale do Paraíba (UNIVAP). São José dos Campos , SP, Brazil
• Associated research grant: 06/02467-0 - The formation of high mass stars, AP.JP

Abstract

Massive stars have an important role in the evolution of galaxies. They are the source of heavy elements, momentum, mass and energy, injected in the interstellar medium. The ultraviolet radiation from these hot stars heats the dust in pre-stellar molecular clouds e give rise ultracompact HII regions. However, important questions, such as the lifetime in HII regions, the statistics of star embedded in molecular clouds amd their formation rate in the Milky Way still remain opened. Because they are embedded in their natal clouds, massive stars remain invisible at optical wavelengths until their process of formation is finished e the star is already at the main sequence. The high opacity in massive star forming regions at visible wavelengths precludes the identification of candidates for the ionizing source of a ultracompact HII region. This project will take advantage of observational techniques at the near and mid infrared, benefiting from the lower opacity at theses wavelengths, to identify and characterize the infrared counterparts of ultracompact HII regions.