Highly turbulent gas on GMC scales in NGC 3256, the nearest luminous infrared galaxy
Artikel i vetenskaplig tidskrift, 2021

We present the highest resolution CO (2-1) observations obtained to date (0.25 arcsec) of NGC 3256 and use them to determine the detailed properties of the molecular interstellar medium in the central 6 kpc of this merger. Distributions of physical quantities are reported from pixel-by-pixel measurements at 55 and 120 pc scales and compared to disc galaxies observed by PHANGS-ALMA (Physics at High Angular resolution in Nearby GalaxieS with Atacama Large Millimeter/Submillimeter Array). Mass surface densities range from 8 to 5500 M-circle dot pc(-2) and velocity dispersions from 10 to 200 km s(-1). Peak brightness temperatures as large as 37 K are measured, indicating the gas in NGC 3256 may be hotter than all regions in nearby disc galaxies measured by PHANGS-ALMA. Brightness temperatures even surpass those in the overlap region of NGC 4038/9 at the same scales. The majority of the gas appears unbound with median virial parameters of 7-19, although external pressure may bind some of the gas. High internal turbulent pressures of 10(5)-10(10) K cm(-3) are found. Given the lack of significant trends in surface density, brightness temperature, and velocity dispersion with physical scale we argue the molecular gas is made up of a smooth medium down to 55 pc scales, unlike the more structured medium found in the PHANGS-ALMA disc galaxies.

galaxies: ISM

ISM: clouds

galaxies: interactions

ISM: kinematics and dynamics

galaxies: jets

ISM: jets and outflows

Författare

Nathan Brunetti

McMaster University

Christine D. Wilson

McMaster University

Kazimierz Sliwa

Max-Planck-Gesellschaft

Eva Schinnerer

Max-Planck-Gesellschaft

Susanne Aalto

Chalmers, Rymd-, geo- och miljövetenskap, Astronomi och plasmafysik

Alison B. Peck

Northern Operat Ctr, Gemini Observ, 67-0 N AOhoku Pl

Monthly Notices of the Royal Astronomical Society

0035-8711 (ISSN) 1365-2966 (eISSN)

Vol. 500 4 4730-4748

Ämneskategorier

Energiteknik

Meteorologi och atmosfärforskning

Astronomi, astrofysik och kosmologi

DOI

10.1093/mnras/staa3425

Mer information

Senast uppdaterat

2021-02-11