Jet‐ and Wind‐driven Ionized Outflows in the Superbubble and Star‐forming Disk of NGC 3079 (original) (raw)
Related papers
A 60 kpc Galactic Wind Cone in NGC 3079
The Astrophysical Journal
Galactic winds are associated with intense star formation and AGNs. Depending on their formation mechanism and velocity they may remove a significant fraction of gas from their host galaxies, thus suppressing star formation, enriching the intergalactic medium, and shaping the circumgalactic gas. However, the long-term evolution of these winds remains mostly unknown. We report the detection of a wind from NGC 3079 to at least 60 kpc from the galaxy. We detect the wind in FUV line emission to 60 kpc (as inferred from the broad FUV filter in GALEX) and in X-rays to at least 30 kpc. The morphology, luminosities, temperatures, and densities indicate that the emission comes from shocked material, and the O/Fe ratio implies that the X-ray emitting gas is enriched by Type II supernovae. If so, the speed inferred from simple shock models is about 500 km s −1 , which is sufficient to escape the galaxy. However, the inferred kinetic energy in the wind from visible components is substantially smaller than canonical hot superwind models.
The Collimated Wind in NGC 253
The Astrophysical Journal, 2003
Near-infrared Fabry-Perot imaging has revealed H 2 emission extended to about 130 pc from the disk of NGC 253. It is closely related to the hot plasma observed in soft X-rays: filamentary H 2 features are found at the edges of the hot plasma. These are the places of direct interaction between a superwind and its surrounding molecular gas. We suggest that the filamentary features actually trace a more or less conical shell-like structure, whose tangential line of sight to us is intensely observed. The H 2 emission shell is most likely from the molecular gas blown out or swept to the side by the hot plasma outflow. Dust is associated with this molecular gas structure. The outflow is tilted with respect to the disk, possibly suggesting the inhomogeneous nature of the interstellar medium in which the starburst takes place.
The Optical Structure of the Starburst Galaxy M82. I. Dynamics of the Disk and Inner-Wind
The Astrophysical Journal, 2009
We present Gemini-North GMOS-IFU observations of the central starburst clumps and inner wind of M82, together with WIYN DensePak IFU observations of the inner 2 × 0.9 kpc of the disk. These cover the emission lines of Hα, [N ii], [S ii], and [S iii] at a spectral resolution of 45-80 km s −1 . The high signal-to-noise of the data is sufficient to accurately decompose the emission line profiles into multiple narrow components (FWHM ∼ 30-130 km s −1 ) superimposed on a broad (FWHM ∼ 150-350 km s −1 ) feature. This paper is the first of a series examining the optical structure of M82's disk and inner wind; here we focus on the ionized gaseous and stellar dynamics and present maps of the relevant emission line properties.
The Optical Structure of the Starburst Galaxy M82. II. Nebular Properties of the Disk and Inner Wind
The Astrophysical Journal, 2009
In this second paper of the series, we present the results from optical Gemini-North GMOS-IFU and WIYN DensePak IFU spectroscopic observations of the starburst and inner wind zones of M82, with a focus on the state of the T ∼ 10 4 K ionized interstellar medium. Our electron density maps show peaks of a few 1000 cm −3 (implying very high thermal pressures), local small spatial-scale variations, and a fall-off in the minor axis direction. We discuss the implications of these results with regards to the conditions/locations that may favour the escape of individual cluster winds that ultimately power the large-scale superwind.
Star formation driven galactic winds in UGC 10043
Monthly Notices of the Royal Astronomical Society, 2016
We study the galactic wind in the edge-on spiral galaxy UGC 10043 with the combination of the CALIFA integral field spectroscopy data, scanning Fabry-Perot interferometry (FPI) and multiband photometry. We detect ionized gas in the extraplanar regions reaching a relatively high distance, up to ∼4 kpc above the galactic disc. The ionized gas line ratios ([N II]/Hα, [S II]/Hα and [O I]/Hα) present an enhancement along the semiminor axis, in contrast with the values found at the disc, where they are compatible with ionization due to H II-regions. These differences, together with the biconic symmetry of the extra-planar ionized structure, make UGC 10043 a clear candidate for a galaxy with gas outflows ionizated by shocks. From the comparison of shock models with the observed line ratios, and the kinematics observed from the FPI data, we constrain the physical properties of the observed outflow. The data are compatible with a velocity increase of the gas along the extraplanar distances up to <400 km s −1 and the pre-shock density decreasing in the same direction. We also observe a discrepancy in the SFR estimated based on Hα (0.36 M yr −1) and that estimated with the CIGALE code, the latter being five times larger. Nevertheless, this SFR is still not enough to drive the observed galactic wind if we do not take into account the filling factor. We stress that the combination of the three techniques of observation with the models is a powerful tool to explore galactic winds in the Local Universe.
2016
We present an analysis of the Mg II λλ2796, 2803 and Fe II λλ2586, 2600 absorption line profiles in individual spectra of 105 galaxies at 0.3 < z < 1.4. The galaxies, drawn from redshift surveys of the GOODS fields and the Extended Groth Strip, fully sample the range in star formation rates (SFRs) occupied by the star-forming sequence with stellar masses log M * /M ⊙ 9.5 at 0.3 < z < 0.7. Using the Doppler shifts of the Mg II and Fe II absorption lines as tracers of cool gas kinematics, we detect large-scale winds in 66 ± 5% of the galaxies. High-resolution Hubble Space Telescope/Advanced Camera for Surveys imaging and our spectral analysis indicate that the outflow detection rate depends primarily on galaxy orientation: winds are detected in ∼ 89% of galaxies having inclinations (i) < 30 • (face-on), while the wind detection rate is only ∼ 45% in objects having i > 50 • (edge-on). Combined with the comparatively weak dependence of the wind detection rate on intrinsic galaxy properties (including SFR surface density), this suggests that biconical outflows are ubiquitous in normal, starforming galaxies at z ∼ 0.5, with over half of the sample having full wind cone opening angles of ∼ 100 •. We find that the wind velocity is correlated with host galaxy M * at 3.4σ significance, while the equivalent width (EW) of the flow is correlated with host galaxy SFR at 3.5σ significance, suggesting that hosts with higher SFR may launch more material into outflows and/or generate a larger velocity spread for the absorbing clouds. The large (> 1Å) Mg II outflow EWs typical of this sample are rare in the context of Mg II absorption studies along QSO sightlines probing the extended halos of foreground galaxies, implying that this wind material is not often detected at impact parameters > 10 kpc. Assuming that the gas is launched into dark matter halos with simple, isothermal density profiles, the wind velocities measured for the bulk of the cool material (∼ 200 − 400 km s −1) are sufficient to enable escape from the halo potentials only for the lowest-M * systems in the sample. However, the highest-velocity gas in the outflows typically carries sufficient energy to reach distances of 50 kpc, and may therefore be a viable source of cool material for the massive circumgalactic medium observed around bright galaxies at z ∼ 0.
The Astrophysical Journal, 2002
Using Chandra and HST we show that X-ray and Hα filaments that form the 1.3-kpc diameter superbubble of NGC 3079 have strikingly similar patterns at ∼0. ′′ 8 resolution. This tight optical line/X-ray match seems to arise from cool disk gas that has been driven by the wind, with X-rays being emitted from upstream, stand-off bowshocks or by conductive cooling at the cloud/wind interfaces. We find that the soft X-ray plasma has thermal and kinetic energies E TH ∼ 2 × 10 56 η 0.5
Preprint typeset using LATEX style emulateapj v. 11/10/09 DUST-DRIVEN WIND FROM DISK GALAXIES
2013
We study gaseous outflows from disk galaxies driven by radiation pressure on dust grains. We include the effect of bulge and dark matter halo and show that the existence of such an outflow implies a maximum value of disk mass-to-light ratio. We show that the terminal wind speed is proportional to the disk rotation speed in the limit of a cold gaseous outflow, and that in general there is a contribution from the gas sound speed. Using the mean opacity of dust grains and the evolution of the luminosity of a simple stellar population, we then show that the ratio of the wind terminal speed (v ∞) to the galaxy rotation speed (v c) ranges between 2-3 for a period of ∼ 10 Myr after a burst of star formation, after which it rapidly decays. This result is independent of any free parameter and depends only on the luminosity of the stellar population and on the relation between disk and dark matter halo parameters. We briefly discuss the possible implications of our results.
The gas component plays a major role in the dynamics of spiral galaxies, because of its dissipative character, and its ability to exchange angular momentum with stars in the disk. Due to its small velocity dispersion, it triggers gravitational instabilities, and the corresponding non-axisymmetric patterns produce gravity torques, which mediate these angular momentum exchanges. When a srong bar pattern develops with the same pattern speed all over the disk, only gas inside corotation can flow towards the center. But strong bars are not long lived in presence of gas, and multiple-speed spiral patterns can develop between bar phases, and help the galaxy to accrete external gas flowing from cosmic filaments. The gas is then intermittently driven to the galaxy center, to form nuclear starbursts and fuel an active nucleus. The various time-scales of these gaseous flows are described.
Dust-driven Wind from Disk Galaxies
Astrophysical Journal, 2011
We study gaseous outflows from disc galaxies driven by radiation pressure on dust grains. We include the effect of bulge and dark matter halo and show that the existence of such an outflow implies a maximum value of disc mass-to-light ratio. We show that the terminal wind speed is proportional to the disc rotation speed in the limit of a cold gaseous outflow, and that in general there is a contribution from the gas sound speed. Using the mean opacity of dust grains and the evolution of the luminosity of a simple stellar population, we then show that the ratio of the wind terminal speed ($v_\infty$) to the galaxy rotation speed ($v_c$) ranges between 2hbox−−32 \hbox{--} 32hbox−−3 for a period of sim10\sim 10sim10 Myr after a burst of star formation, after which it rapidly decays. This result is independent of any free parameter and depends only on the luminosity of the stellar population and on the relation between disc and dark matter halo parameters. We briefly discuss the possible implications of our results.