An Investigation of Disk Thickness in M51 from Hα, Paα, and Mid-infrared Power Spectra
Abstrak
Power spectra (PS) of high-resolution images of M51 (NGC 5194) taken with the Hubble Space Telescope and the James Webb Space Telescope (JWST) have been examined for evidence of disk thickness in the form of a change in slope between large scales, which map two-dimensional correlated structures, and small scales, which map three-dimensional correlated structures. Such a slope change is observed here in H α , and possibly Pa α , using average PS of azimuthal intensity scans that avoid bright peaks. The physical scale of the slope change occurs at ∼120 pc and ∼170 pc for these two transitions, respectively. A radial dependence in the shape of the H α PS also suggests that the length scale drops from ∼180 pc at 5 kpc, to ∼90 pc at 2 kpc, to ∼25 pc in the central ∼kpc. We interpret these lengths as comparable to the thicknesses of the star-forming disk traced by H ii regions. The corresponding emission measure is ∼100 times larger than what is expected from the diffuse ionized gas. The PS of JWST Mid-IR Instrument images in eight passbands have more gradual changes in slope, making it difficult to determine a specific value of the thickness for this emission.
Topik & Kata Kunci
Penulis (30)
Bruce G. Elmegreen
Daniela Calzetti
Angela Adamo
Karin Sandstrom
Daniel Dale
Varun Bajaj
Martha L. Boyer
Ana Duarte-Cabral
Ryan Chown
Matteo Correnti
Julianne J. Dalcanton
Bruce T. Draine
Brandt Gaches
John S. Gallagher III
Kathryn Grasha
Benjamin Gregg
Leslie K. Hunt
Kelsey E. Johnson
Robert Kennicutt Jr.
Ralf S. Klessen
Adam K. Leroy
Sean Linden
Anna F. McLeod
Matteo Messa
Göran Östlin
Mansi Padave
Julia Roman-Duval
J. D. Smith
Fabian Walter
Tony D. Weinbeck
Akses Cepat
- Tahun Terbit
- 2025
- Sumber Database
- DOAJ
- DOI
- 10.3847/1538-4357/adcee6
- Akses
- Open Access ✓