The Intrinsic Shapes of Low Surface Brightness Galaxies (LSBGs): A Discriminant of LSBG Galaxy Formation Mechanisms

Journal Article · Fri Oct 15 00:00:00 EDT 2021 · The Astrophysical Journal

DOI:https://doi.org/10.3847/1538-4357/ac15f0· OSTI ID:1983180

Kado-Fong, Erin ^[1]; Petrescu, Mihai ^[2]; Mohammad, Majid ^[3]; Greco, Johnny ^[2]; Greene, Jenny E. ^[1]; Adams, Elizabeth A. K. ^[4]; Huang, Song ^[1]; Leisman, Lukas ^[5]; Munshi, Ferah ^[6]; Tanoglidis, Dimitrios ^[7]; Van Nest, Jordan ^[6]

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1. Princeton University, NJ (United States)
2. The Ohio State University, Columbus, OH (United States)
3. Colorado School of Mines, Golden, CO (United States)
4. ASTRON, the Netherlands Institute for Radio Astronomy (Netherlands); Kapteyn Astronomical Institute, Groningen (Netherlands)
5. Valparaiso University, IN (United States)
6. University of Oklahoma, Norman, OK (United States)
7. University of Chicago, IL (United States)

We use the low surface brightness galaxy (LSBG) samples created from the Hyper Suprime-Cam Subaru Strategic Program (781 galaxies), the Dark Energy Survey (20977 galaxies), and the Legacy Survey (selected via H ι detection in the Arecibo Legacy Fast ALFA Survey, 188 galaxies) to infer the intrinsic shape distribution of the LSBG population. To take into account the effect of the surface brightness cuts employed when constructing LSBG samples, we simultaneously model both the projected ellipticity and the apparent surface brightness in our shape inference. We find that the LSBG samples are well characterized by oblate spheroids, with no significant difference between red and blue LSBGs. This inferred shape distribution is in good agreement with similar inferences made for ultra-diffuse cluster galaxy samples, indicating that environment does not play a key role in determining the intrinsic shape of LSBGs. In this study, we also find some evidence that LSBGs are more thickened than similarly massive high surface brightness dwarfs. We compare our results to intrinsic shape measures from contemporary cosmological simulations, and find that the observed LSBG intrinsic shapes place considerable constraints on the formation path of such galaxies. In particular, LSBG production via the migration of star formation to large radii produces intrinsic shapes in good agreement with our observational findings.

• Research Organization: Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). National Energy Research Scientific Computing Center (NERSC); SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)
• Sponsoring Organization: National Science Foundation (NSF); USDOE Office of Science (SC), Basic Energy Sciences (BES). Scientific User Facilities (SUF); USDOE Office of Science (SC), High Energy Physics (HEP)
• Grant/Contract Number: AC02-05CH11231
• OSTI ID: 1983180
• Journal Information: The Astrophysical Journal, Journal Name: The Astrophysical Journal Journal Issue: 2 Vol. 920; ISSN 0004-637X
• Publisher: IOP Publishing
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
astronomical methods
dwarf galaxies
galaxy structure
low surface brightness galaxies
observational astronomy