THE TURBULENCE VELOCITY POWER SPECTRUM OF NEUTRAL HYDROGEN IN THE SMALL MAGELLANIC CLOUD

Journal Article · Tue Sep 01 04:00:00 EDT 2015 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/810/1/33· OSTI ID:22525515

Chepurnov, A.; Lazarian, A.; Stanimirovic, S. ^[1]; Burkhart, B. ^[2]

---

1. Astronomy Department, University of Wisconsin, Madison, 475 N. Charter St., WI 53711 (United States)
2. Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 0213 (United States)

We present the results of the Velocity Coordinate Spectrum (VCS) technique to calculate the velocity power spectrum of turbulence in the Small Magellanic Cloud (SMC) in 21 cm emission. We present an updated version of the VCS technique that takes into account regular motions, which is an important factor in our SMC VCS analysis. We have obtained a velocity spectral index of −3.85, a cold phase sonic Mach number of 5.6, and an injection scale of 2.3 kpc. The spectral index is steeper than the Kolmogorov index, which is expected for shock-dominated turbulence. The injection scale of 2.3 kpc suggests that HI supershells or tidal interactions with the Large Magellanic Cloud are the dominant drivers of turbulence in this dwarf galaxy. This implies that turbulence may be driven by multiple mechanisms in galaxies and that galaxy–galaxy interactions may play an important role in addition to supernova feedback.

• OSTI ID: 22525515
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 1 Vol. 810; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
COORDINATES
EMISSION SPECTRA
FEEDBACK
HYDROGEN
INDEXES
MACH NUMBER
MAGELLANIC CLOUDS
MAGNETOHYDRODYNAMICS
TURBULENCE