New Insights into the Early Stages of Massive Star Formation

Cyganowski Claudia J, Madison WI

Investigators

Abstract

Dr. Claudia Cyganowski is awarded an NSF Astronomy and Astrophysics Postdoctoral Fellowship to carry out a program of research and education at the Harvard-Smithsonian Center for Astrophysics, the National Radio Astronomy Observatory, and the University of Virginia. Massive star formation remains a poorly understood phenomenon, largely due to the difficulty of identifying and studying massive young stellar objects (MYSOs) in the crucial early stage of active accretion. Dr. Cyganowski's research will probe the importance of protostellar feedback in the formation of massive star clusters by observing a unique new sample of MYSOs presently in their active accretion and outflow phase. Identified based on their extended 4.5-micron emission in Spitzer Space Telescope images, these sources are known as Extended Green Objects (EGOs) from the common coding of the 4.5-micron band as green in three-color Spitzer images. Massive stars generally form in clusters, in distant (>1 kpc) and deeply embedded massive star-forming regions. The high angular resolution and sensitivity of the Expanded Very Large Array (EVLA) and the Atacama Large Millimeter/submillimeter Array (ALMA) at unextincted cm-(sub)mm wavelengths will provide revolutionary new capabilities for MYSO studies. Dr. Cyganowski will use sensitive, high angular resolution cm-sub(mm) line and continuum observations of EGOs to: (1) characterize the masses and clustering properties of compact cores associated with 4.5-micron outflows; (2) constrain the relative importance of different feedback mechanisms (e.g. outflows, heating, ionization); and (3) place EGOs in an evolutionary sequence of massive protostars, relative to each other and to MYSOs from other samples. In sum, the research will use new observational capabilities at cm-(sub)mm wavelengths to address key questions of how protostellar feedback during the formation process affects the masses, number, and clustering properties of the resulting stars, and to assemble a robust observationally-based evolutionary sequence for MYSOs. Dr. Cyganowski will also broaden science education in rural elementary schools by means of the outreach program "Dark Skies, Bright Kids" (DSBK). DSBK combines an after-school astronomy club for students with onsite night-sky viewing for both students and their families with portable telescopes. Her educational and outreach activities will focus on expanding DSBK to reach students from underrepresented minority groups, through both elementary schools and other organizations, including local Boys and Girls Clubs.