Blonk, Adriana Julia (2024) Resolved HI imaging of potential dark galaxy candidate AGC268071. Bachelor's Thesis, Astronomy.
|
Text
BachelorThesisAJBlonk-1.pdf Download (3MB) | Preview |
|
![[img]](https://fse.studenttheses.ub.rug.nl/style/images/fileicons/text.png) |
Text
toestemming.pdf Restricted to Registered users only Download (183kB) |
Abstract
The study presents insight into the nature of UCHVC AGC 268071, through resolved imaging at original 45” data and 105” resolution data smoothed in the image plane. The source was detected by ALFALFA and has a possible stellar counterpart at 1.5 kpc seperation from the ALFALFA HI detection. The possible nature scenarios discussed are: a gas bearing dark matter mini halo or a gas cloud in the Galactic halo. The interferometric data are flagged, calibrated and cleaned within masked regions. The HI morphology of AGC 268071 appears compact at both resolutions. The source displays a relatively small velocity gradient across its surface. The found velocity dispersion corresponds to a large fraction of CNM gas. The extracted HI line spectra in this research has a lower peak value and width than the ALFALFA spectrum, likely due to Galactic background emission influencing the ALFALFA data or missing source emission in the VLA cleaned datacube due to the low SNR of the data. Assuming a galactic nature of AGC 268071, the HI mass found is 1.87-2.72 x 10^4 M⊙ for 45” data and 1.31-1.89 x 10^4 M⊙ for 105” data. This result means AGC 268071 could be the lowest known HI mass galaxy in the Local Group, but should be considered a lower limit. Based on the compact HI morphology and small velocity gradient AGC 268071 is likely of galactic nature, but the gas cloud in Galactic halo scenario cannot be fully ruled out due to the low measured velocity dispersion.
| Item Type: | Thesis (Bachelor's Thesis) |
|---|---|
| Supervisor name: | Adams, E.A.K. and Oosterloo, T.A. |
| Degree programme: | Astronomy |
| Thesis type: | Bachelor's Thesis |
| Language: | English |
| Date Deposited: | 05 Mar 2025 07:59 |
| Last Modified: | 05 Mar 2025 07:59 |
| URI: | https://fse.studenttheses.ub.rug.nl/id/eprint/34818 |
Actions (login required)
 |
View Item |