Characterizing Bars in Low Surface Brightness Galaxies

• Main Author: Peters, Wesley C.
• Format: Text
• Language: unknown
• Published: ScholarWorks @ Georgia State University 2019
• Subjects: galaxies:structure; galaxies:photometry; Arctic
• Online Access: https://scholarworks.gsu.edu/phy_astr_diss/115; https://doi.org/10.57709/14855693; https://scholarworks.gsu.edu/context/phy_astr_diss/article/1117/viewcontent/peters_wesley_c_201905_phd.pdf

Bars in low surface brightness galaxies (LSBs) are relatively understudied despite being important tools for our understanding of galaxy formation and evolution. Drawing from various LSB surveys, we obtained B- and I-band images from the ARCTIC imager on the 3.5m telescope at Apache Point Observatory of 15 barred LSBs in order to measure the three bar properties: length (Rbar), strength (Sb), and corotation radius (RCR). For 11 of these galaxies, we present new B- and I-band surface brightness profiles, magnitudes, and colors and find that barred LSBs are slightly brighter than the general LSB population, but have similar blue colors. In order to characterize the pattern speed of the bars in LSBs, we use phase crossings of the B- and I-band images to measure the corotation radius and a new bar length measure using azimuthal light profiles to calculate the relative bar pattern speed R ≡ RCR/Rbar. We also assembled a sample of 26 barred high surface brightness galaxies (HSBs) to explore how bar properties correlate with various galaxy properties. We find that Rbar and Sb correlate with galaxy morphology, stellar mass, surface brightness, and gas fraction, but that R does not correlate with any galaxy properties. While previous works have shown bars are fast across morphology and redshift, we have extended this to surface brightness and present the currently largest sample of R measurements for barred LSBs. As LSBs are expected to form in high spin dark matter halos, we estimated the underlying halo spin λ and indeed found high spins of λ > 0.03 for the majority of our barred LSBs. This work sheds light on a relatively understudied galaxy population, and future work will help to put our results into context with our current understanding of galaxy formation and evolution.