Temperature and Metallicity Gradients in the Hot Gas Outflows of M82
| Autor: | Dustin D. Nguyen, Smita Mathur, Laura A. Lopez, Grace M. Olivier, Todd A. Thompson |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
010504 meteorology & atmospheric sciences
Metallicity Astrophysics::High Energy Astrophysical Phenomena Flux FOS: Physical sciences Starburst galaxies Astrophysics Astrophysics::Cosmology and Extragalactic Astrophysics MASS 01 natural sciences Spectral line X-RAY-EMISSION ABUNDANCES DISK Phase (matter) 0103 physical sciences STAR-CLUSTERS Adiabatic process 010303 astronomy & astrophysics Astrophysics::Galaxy Astrophysics 0105 earth and related environmental sciences Physics High Energy Astrophysical Phenomena (astro-ph.HE) SPECTROSCOPY Number density STARBURST CORE Astronomy and Astrophysics Plasma DRIVEN WIND Astrophysics - Astrophysics of Galaxies Galaxy Galactic winds 13. Climate action Space and Planetary Science Astrophysics of Galaxies (astro-ph.GA) Astrophysics - High Energy Astrophysical Phenomena SUPERWIND |
| Zdroj: | Lopez, L A, Mathur, S, Nguyen, D D, Thompson, T A & Olivier, G M 2020, ' Temperature and Metallicity Gradients in the Hot Gas Outflows of M82 ', Astrophysical Journal, vol. 904, no. 2, 152 . https://doi.org/10.3847/1538-4357/abc010 |
| DOI: | 10.48550/arxiv.2006.08623 |
| Popis: | We utilize deep Chandra X-ray Observatory imaging and spectra of M82, the prototype of a starbursting galaxy with a multiphase wind, to map the hot plasma properties along the minor axis of the galaxy. We extract spectra from 11 regions up to 2.5 kpc from the starbursting midplane and model the data as a multi-temperature, optically thin thermal plasma with contributions from a non-thermal (power-law) component and from charge exchange (CX). We examine the gradients in best-fit parameters, including the intrinsic column density, plasma temperature, metal abundances, and number density of the hot gas as a function of distance from the M82 nucleus. We find that the temperatures and number densities of the warm-hot and hot plasma peak at the starbursting ridge and decreases along the minor axis. The temperature and density profiles are inconsistent with spherical adiabatic expansion of a super-heated wind and suggest mass loading and mixing of the hot phase with colder material. Non-thermal emission is detected in all of the regions considered, and CX comprises 8-25% of the total absorption-corrected, broad-band (0.5-7 keV) X-ray flux. We show that the abundances of O, Ne, Mg, and Fe are roughly constant across the regions considered, while Si and S peak within 500 pc of the central starburst. These findings support a direct connection between the M82 superwind and the warm-hot, metal-rich circumgalactic medium (CGM). Comment: 15 pages, 8 figures, ApJ in press |
| Databáze: | OpenAIRE |
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