The effects of starburst activity on low surface brightness disk galaxies

Although numerous simulations have been done to understand the effects of i ntense bursts of star formation on high surface brightness galaxies, few at tempts have been made to understand how localized starbursts would affect b oth the color and surface brightness of low surface brightness (LSB) galaxi es. To remedy this, we have run 53 simulations involving bursts of star for mation activity on LSB galaxies, varying both the underlying galaxy propert ies and the parameters describing the starbursts. We discovered that althou gh changing the total color of a galaxy was fairly straightforward, it was virtually impossible to alter a galaxy's central surface brightness and the reby remove it from the LSB galaxy classification without placing a high la nd fairly artificial) threshold for the underlying gas density. The primary effect of large amounts of induced star formation was to produce a central ized core (bulge) component, which is generally not observed in LSB galaxie s. The noisy morphological appearance of LSB galaxies, as well as their noi sy surface brightness profiles, can be reproduced by considering small burs ts of star formation that are localized within the disk. The trigger mechan ism for such bursts is likely distant/weak tidal encounters. The stability of disk central surface brightness to these periods of star formation argue s that the large space density of LSB galaxies at z=0 should hold to substa ntially higher redshifts.