Spitzer Space Telescope - Guaranteed Time Observer Proposal #50026 MIPS and IRAC Imaging of High Mass Protostellar Cores Principal Investigator: Giovanni Fazio Institution: Harvard-Smithsonian Astrophysical Observatory Technical Contact: Howard Smith, Harvard-Smithsonian Center for Astrophysics Co-Investigators: TK Sridharan, CfA Tushara Pillai, CfA Nimesh Patel, CfA Qizhou Zhang, CfA Joe Hora, CfA Eric Keto, CfA Sergio Molinari, ISFI-Roma Fabiani Faustini, IFSI-Roma Barbara Whitney, Space Science Institute Murray Campbell, Colby College Science Category: star formation Observing Modes: IracMap MipsPhot Hours Approved: 11 Abstract: We propose an infrared study of a thorough set of 140 embedded high mass protostellar cores (HMPOs) that span a range of early types. Our sample is selected from well-studied objects in our previous cm/mm/IR wavelength programs. Most of our embedded core sources are undetected at [K], but are seen by IRAC Band 4 and MSX; all are associated with IRAS luminous sources, and most have some associated molecular outflow. We have limited this sample to those cores probably closer than 5kpc. We propose Spitzer MIPS70 pointed super resolution observations of the 55 sources in our sample that have had no previous MIPS 70um observations; we propose MIPS24 on 29 of these that are unlikely to saturate; and we propose IRAC imaging on 30 with no previous IRAC observations and whose IRAS colors are indicative of stellar neighbors that we want to spatially resolve. We will use these data, to study systematically the character of these high mass protostellar cores. Our team has recently published two new papers on the SEDs of individual objects in our full sample that had been previously observed. Our program includes extensive SED modelling, and the team includes experts in modeling.