Spatially Resolved Recent Star Formation History in NGC 6946
Creators
-
1.
University of Washington
-
2.
California Institute of Technology
- 3. Flatiron Institute
-
4.
Raytheon (United States)
-
5.
University of Arizona
-
6.
Arizona State University
-
7.
Rutgers, The State University of New Jersey
Abstract
The nearby face-on star-forming spiral galaxy NGC 6946 is known as the Fireworks Galaxy due to its hosting an unusually large number of supernovae. We analyze its resolved near-ultraviolet stellar photometry measured from images taken with the Hubble Space Telescope's Wide Field Camera 3 with the F275W and F336W filters. We model the color–magnitude diagrams of the UV photometry to derive the spatially resolved star formation history of NGC 6946 over the last 25 Myr. From this analysis, we produce maps of the spatial distribution of the young stellar population and measure the total recent star formation rate (SFR) of nearly the entire young stellar disk. We find the global SFR(age ≤25 Myr) = 13.17_(−0.79)^(+0.91)M⊙yr⁻¹ . Over this period, the SFR is initially very high (23.39_(−2.11)^(+2.43)M⊙yr⁻¹ 16–25 Myr ago), then monotonically decreases to 5.31_(−0.17)^(+0.19)M⊙yr⁻¹ in the last 10 Myr. This decrease in global SFR over the last 25 Myr is consistent with measurements made with other SFR indicators. We discuss in detail two of the most active regions of the galaxy, which we find are responsible for 3% and 5% of the total star formation over the past 6.3 Myr.
Copyright and License
© 2023. The Author(s). Published by the American Astronomical Society.
Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
Acknowledgement
We thank the reviewer for helpful comments that improved the paper. This research is based on observations made with the NASA/ESA HST obtained from the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with the program GO-15877.
Facilities
HST(WFC3/UVIS) - Hubble Space Telescope satellite.
Software References
astropy (Astropy Collaboration et al. 2013, 2018, 2022), DOLPHOT (Dolphin 2000, 2016), GeoPandas (Jordahl et al. 2020), MATCH (Dolphin 2002, 2012, 2013), Matplotlib (Hunter 2007), NumPy (Harris et al. 2020), Pandas (Wes McKinney 2010; pandas development team 2020).
Files
Tran_2023_ApJ_954_211.pdf
Files
(2.0 MB)
| Name | Size | Download all |
|---|---|---|
|
md5:b335540f72cbe28af39b06fa35657e83
|
2.0 MB | Preview Download |
Additional details
Related works
- Is new version of
- Discussion Paper: arXiv:2307.04853 (arXiv)
Funding
- National Aeronautics and Space Administration
- NAS 5-26555
- Space Telescope Science Institute
- GO-15877
Dates
- Accepted
-
2023-06-29
- Available
-
2023-09-08Published