This paper presents optical and Hα imaging for a large sample of LSB galaxies selected from the PSS-II catalogs (Schombert et al. 1992). As noted in previous work, LSB galaxies span a range of luminosities (−10 > M V > −20) and sizes (0.3 kpc < R V 25 < 10 kpc), although they are consistent in their irregular morphology. Their Hα luminosities (L(Hα) range from 10 36 to 10 41 ergs s −1 (corresponding to a range in star formation, using canonical prescriptions, from 10 −5 to 1 M yr −1 ). Although their optical colors are at the extreme blue edge for galaxies, they are similar to the colors of dwarf galaxies (van Zee 2001) and gas-rich irregulars (Hunter & Elmegreen 2006). However, their star formation rates per unit stellar mass are a factor of ten less than other galaxies of the same baryonic mass, indicating that they are not simply quiescent versions of more active star forming galaxies. This paper presents the data, reduction techniques and new philosophy of data storage and presentation. Later papers in this series will explore the stellar population and star formation history of LSB galaxies using this dataset. arXiv:1109.2360v1 [astro-ph.CO] 11 Sep 2011 -2 -4449 (Huchra et al. 1983). The advent of newer all-sky surveys in the 1980's/90's demonstrated the importance of low surface brightness (LSB) galaxies to the galaxy population, and opened up a wider range of irregular late-type galaxies for study. Although initial suggestions were that LSB galaxies dominate the total galaxy population of the Universe over their higher surface brightness (HSB) cousins, it was later found to be untrue (Rosenbaum & Bomans 2004, Hayward, Irwin & Bergman 2005. Nonetheless, LSB galaxies offer a new avenue for the study of galaxy evolution, having low stellar densities and recent star formation rates. Their study, as a class of galaxies, has merit for stellar population work.Star formation in galaxies falls into three crude categories: 1) hyper-efficient, typically associated with tidal or merger events (Whitmore et al. 2005), 2) normal, associated spiral galaxies under density wave or stochastic processes (Young et al. 1996) and 3) bursts followed by long quiescent periods, typically associated with dwarf galaxies (Schombert et al. 2001). LSB galaxies, almost by definition, are found in the third category and are assumed to have had below average star formation rates for their entire lifetimes to explain their star-forming blue colors, yet low stellar densities.This project is focused on obtaining optical and Hα imaging of a sample of LSB galaxies with known HI properties. For knowledge of the blue optical colors, Hα emission and HI gas mass provides constraints on the dominant stellar population for the last few Gyrs, the current star formation rate and the potential total star formation rate (i.e., the amount of material available to produce stars). Integrated values speak to the global history of star formation, but, in addition, spatial color and Hα information can distinguish between episodic bursts of star formation ve...

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There is mounting evidence that mechanical radio source feedback is important in galaxy evolution and in order to quantify this feedback, detailed models of radio source evolution are required. We present an extension to current analytic models that encompasses young radio sources with physical sizes on sub-kiloparsec scales. This work builds on an existing young source dynamical model to include radiative losses in a flat environment, and as such, is the best physically-motivated Compact Symmetric Object model to date. Results predict that young radio sources experience significant radiative loss on length scales and spectral scales consistent with observed Compact Steep-Spectrum sources. We include full expressions for the transition to self-similar expansion and present this complete model of radio source evolution from first cocoon formation to end of source lifetime around 10 8 years within the context of a simplified King profile external atmosphere.

Abstract. There is mounting evidence that mechanical kinetic-mode AGN feedback is important in galaxy evolution, and in order to quantify this feedback, detailed models of radio source evolution are required. Self-similar analytic models exist for large powerful radio sources but the evolution of young precursor radio sources is not yet fully understood. In this talk we present a versatile dynamical and radiative model for young source evolution on sub-kiloparsec scales, which extends existing self-similar models into a more complete radio source evolutionary model. This semi-analytic model is successful in reproducing the strong spectral aging observed in compact symmetric objects.