The Extended Optical Disk of M101
Chris Mihos, Paul Harding, Chelsea Spengler, Craig Rudick, and John, Feldmeier

TL;DR
Deep optical imaging of M101's outskirts reveals extended, asymmetric stellar structures and clues about past interactions, star formation, and disk evolution over long timescales.
Contribution
This study provides the deepest optical imaging of M101's outer disk, revealing extended structures and insights into its interaction history and star formation in the outskirts.
Findings
Extended stellar structures detected out to 50 kpc.
Asymmetric plume with blue colors indicating recent star formation.
No evidence of recent major tidal tails.
Abstract
We have used deep, wide-field optical imaging to study the faint outskirts of the luminous spiral galaxy M101 (NGC 5457), as well as its surrounding environment. Over six square degrees, our imaging has a limiting surface brightness of mu_B ~ 29.5 mag/arcsec^2, and has revealed the stellar structure of M101's disk out to nearly 25 arcminutes (50 kpc), three times our measured R25 isophotal size of the optical disk. At these radii, the well-known asymmetry of the inner disk slews 180 degrees, resulting in an asymmetric plume of light at large radius which follows the very extended HI disk to the northeast of M101. This plume has very blue colors (B-V ~ 0.2), suggesting it is the somewhat more evolved (few hundred Myr to ~ 1 Gyr) counterpart of the young far ultraviolet emitting population traced by GALEX imaging. We also detect another, redder spur of extended light to the east of the…
Peer Reviews
No public reviews on file for this paper yet. If you reviewed it on a platform where reviews are public (OpenReview, ICLR, NeurIPS, ICML), you can paste yours below so the community can read it here.
Videos
No videos yet. Explain this paper in a talk, walkthrough, or lecture? Add one.
