• Bernard, J.
• Blum, R.
• Indebetouw, R.
• Meade, M.
• Whitney, B.
• Vijh, U.
• Misselt, K.
• Block, M.
• For, B.
• Engelbracht, C.
• Team, S.
• Meixner, Margaret
• Leitherer, C.
• Hora, J.
• Babler, B.
• Gordon, K.
• Tielens, A. G.

Abstract

We are performing a uniform and unbiased imaging survey of the Large Magellanic Cloud (LMC,77), using the IRAC (3.6, 4.5, 5.8 and 8 m) and MIPS (24, 70, and 160 m) instruments on board the Spitzer Space Telescope (Spitzer) in order to survey the agents of a galaxy’s evolution (SAGE), through the interaction between the interstellar medium (ISM) and stars in the LMC. This presentation provides an overview of the SAGE legacy project including observing strategy, data processing and initial results. Three key science goals determined the coverage and depth of the survey. The detection of diffuse ISM with column densities 〉1.2x10^21 H cm-2 permits detailed studies of dust processes in the ISM. SAGE’s point source sensitivity enables a complete census of newly formed stars with masses 〉3 solar masses that will determine the current star formation rate in the LMC. SAGE’s detection of evolved stars with mass loss rates 〉1x10^-8 M/yr will quantify the rate at which evolved stars inject mass into the ISM of the LMC. The observing strategy includes two epochs in 2005, separated by three months, that both mitigate instrumental artifacts and constrain source variability. The SAGE data are non-proprietary and point source lists will be released to the community in support of Spitzer proposal cycles 4 and 5. The SAGE epoch 1 point source catalog has4x10^6 sources and a measured point source sensitivity for the epoch 1 data is consistent with expectations for the survey. We will briefly review the characteristics of this catalog that has been released to the community.The SAGE Project is supported by NASA/Spitzer grant 1275598 and NASA NAG5-12595.

Topics

• impedance spectroscopy