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HI in the M31/M33 Environment
Free, Nicole Lynn

2010, Master of Science (MS), Ohio University, Physics and Astronomy (Arts and Sciences).

With recent debate about a reported neutral hydrogen, HI, streamer between M33 and M31, we set out to determine the existence of the HI streamer. Using the National Radio Astronomy Observatory’s 100 m Green Bank Telescope, with 9.1´ angular resolution, we mapped the HI in the region from Wright’s Cloud and M33 through the location of the streamer features, as reported by Braun and Thilker (2004). To verify the findings of Braun and Thilker, we also performed pointed observations at two of the three local maxima within their maps.

From our observations, we were able to confirm the existence of the three local maxima points. The three features have column densities ranging from 2.3 x 1017 cm-2 to 5.4 x 1018 cm-2, with most being of the order of magnitude of the latter. The masses of the features range from 6.6 x 104 to 2.2 x 105 solar masses (M). All of the features appear to have more structure and be more compact than previously thought. After examining the Wright’s Cloud region to determine if there was any comparable Galactic HI in the region, it was found that these features are inconsistent with the Galactic High Velocity Clouds in the area of observation. Though the origin of the streamer features cannot concretely be set, with the Pan-Andromeda Archeological Survey's (PAndAS) findings of optical evidence of recent interaction between M33 and M31, the origin of the features from such an interaction remains probable.

Kenneth Hicks (Committee Chair)
Joseph Shields (Advisor)
Felix Lockman (Advisor)
Nancy Sandler (Committee Member)
70 p.

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Free, Nicole. "HI in the M31/M33 Environment." Electronic Thesis or Dissertation. Ohio University, 2010. OhioLINK Electronic Theses and Dissertations Center. 28 May 2018.

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Free, Nicole "HI in the M31/M33 Environment." Electronic Thesis or Dissertation. Ohio University, 2010.


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