Assigned ID: 901 ----- Attempting Submission 1 (Sat Feb 27 00:24:27 GMT 2010) ----- HST Phase I Proposal 901 (hubbleAR-phase1-kaleida.apt) successfully submitted. ----- Attempting Submission 2 (Sat Feb 27 00:47:05 GMT 2010) ----- HST Phase I Proposal 901 (hubbleAR-phase1-kaleida.apt) successfully submitted. ----- Attempting Submission 3 (Sat Feb 27 00:56:33 GMT 2010) ----- HST Phase I Proposal 901 (hubbleAR-phase1-kaleida.apt) successfully submitted. ----- Attempting Submission 4 (Sat Feb 27 00:58:43 GMT 2010) ----- We propose to catalog the stellar associations and clusters in a set of ~50 nearby galaxies. Our primary goals are to assess the fraction of stars that are born in the field versus in clusters, and to determine the timescales for the disruption of the star clusters asa function of size, density, and mass. We will make extensive use of the source lists available through the Hubble Legacy Archive (HLA) to make this a practical reality. The galaxies in our sample have observations in the UBVI and H-alpha bands, using a combination of the ACS and WFPC2 detectors. This will allow for selection of stellar associations in various bands, subsequent age-dating of each association or cluster using Spectal Energy Distribution (SED) fitting, and the determination of red/blue stellar fraction in the associations. Once the stellar clusters and associations have been identified and age-dated, we can deduce disruption times from the age distribution (i.e., the dN/dt diagram) as a function of a variety of properties, including the morphological type of the galaxy, the position of the cluster/association within the galaxy, and the existence of global versus flocculent spiral structure. Some of our primary questions include: Are there prefered size scales for stellar clustering or does clustering of stars occur continuously on all size scales? What is the disruption time for the different size scales? Are these disruption times uniform in the nearby universe, or are they dependent on local galactic environment? In the process of answering these questions, we will produce compreshensive catalogs of stellar groupings on all scales, to complement and enhance the catalogs already available through the HLA.

UNRESOLVED STELLAR POPULATIONS AND GALAXY STRUCTURE 12 96440 Budget for 12 months false 0.0 0.0 false false false false false false SUPPORTED