PI: John Feldmeier, Youngstown State University, firstname.lastname@example.org
Address: Department of Physics and Astronomy, One University Plaza, Youngstown, OH 44555, USA
CoI: Robin Ciardullo, Penn State University
CoI: George Jacoby, NOAO
CoI: Patrick Durrell, Youngstown State University
Title: Searching for Planetary Nebulae in Ursa Major: Studies of the Tully- Fisher relation and Intracluster Light
Abstract: We propose an [O III] (lambda) 5007 MOSAIC survey for planetary nebulae in four fields located within the Ursa Major galaxy cluster. These data will be used for two different programs: \textbf1) We will use the [O III] planetary nebula luminosity function to derive the distances to at least four of Ursa Major's spiral galaxies. Despite its importance to the Tully-Fisher (TF) distance indicator, there is still no stellar-based distance to the group, and no information on the system's line-of-sight depth. Our observations will produce an independent measure of the intrinsic scatter of the TF relation, and thereby help constrain models of galaxy formation and evolution.\hfil\linebreak \textbf2) We will use our images of Ursa Major's intracluster space to measure (or place a limit) on the system's intracluster stars. Theory and observations provide mixed results on the amount of intracluster starlight in galaxy groups. Our previous surveys suggest that the fraction of intracluster stars drops suddenly (by a factor of ~ 10) as one moves from the richer clusters to the smaller groups. If real, this ``intracluster star cliff'' implies that there is something special about the cluster environment that promotes intracluster star production. Ursa Major lies midway in richness and dwarf galaxy properties between the two cluster regimes studied to date. It is therefore a key environment for constraining the existence and steepness of the ``cliff.'' This project was previously awarded time, but due to atrocious weather, we only obtained useful data on one night. We are therefore proposing for time to complete this project.
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