6 research outputs found
Unveiling the complex circumgalactic medium: a comparative study of merging and non-interacting galaxy groups
DUVET Survey: Mapping Outflows in the Metal-Poor Starburst Mrk 1486
We present a method to characterize star-formation driven outflows from
edge-on galaxies and apply this method to the metal-poor starburst galaxy, Mrk
1486. Our method uses the distribution of emission line flux (from H and
[OIII] 5007) to identify the location of the outflow and measure the extent
above the disk, the opening angle, and the transverse kinematics. We show that
this simple technique recovers a similar distribution of the outflow without
requiring complex modelling of line-splitting or multi-Gaussian components, and
is therefore applicable to lower spectral resolution data. In Mrk 1486 we
observe an asymmetric outflow in both the location of the peak flux and total
flux from each lobe. We estimate an opening angle of depending
on the method and assumptions adopted. Within the minor axis outflows, we
estimate a total mass outflow rate of M yr, which
corresponds to a mass loading factor of . We observe a non-negligible
amount of flux from ionized gas outflowing along the edge of the disk
(perpendicular to the biconical components), with a mass outflow rate
M yr. Our results are intended to demonstrate a method that
can be applied to high-throughput, low spectral resolution observations, such
as narrow band filters or low spectral resolution IFS that may be more able to
recover the faint emission from outflows.Comment: 12 Pages, 6 Figure
DUVET: Spatially Resolved Observations of Star Formation Regulation via Galactic Outflows in a Starbursting Disk Galaxy
We compare 500~pc scale, resolved observations of ionised and molecular gas
for the starbursting disk galaxy IRAS08339+6517, using measurements
from KCWI and NOEMA. We explore the relationship of the star formation driven
ionised gas outflows with colocated galaxy properties. We find a roughly linear
relationship between the outflow mass flux () and star
formation rate surface density (), , and a strong correlation between
and the gas depletion time, such that
. Moreover, we find these
outflows are so-called ``breakout" outflows, according to the relationship
between the gas fraction and disk kinematics. Assuming that ionised outflow
mass scales with total outflow mass, our observations suggest that the regions
of highest in IRAS08 are removing more gas via the outflow
than through the conversion of gas into stars. Our results are consistent with
a picture in which the outflow limits the ability for a region of a disk to
maintain short depletion times. Our results underline the need for resolved
observations of outflows in more galaxies.Comment: 16 pages, 7 figures, Submitted to Ap
Constraining variations in the stellar initial mass function with the Fornax3D Survey
Empirical thesis.Bibliography: pages 61-69.1. Introduction -- 2. The data -- 3. Constraining the IMF -- 4. Conclusion -- Appendix -- References.The stellar initial mass function (IMF) describes the distribution of stellar masses when a population of stars first forms. It is a particularly crucial property connecting many different phenomena within a galaxy. Defining the IMF of a galaxy is therefore critical for helping us to understand how galaxies evolve over cosmic time. However, defining the IMF has been the subject of vigorous debate over the past few decades. Recent evidence from early-type galaxies which appear to become more dwarf star rich as galactic mass increases supports a variable rather than universal IMF. With improvements in technology, the question of whether the IMF varies spatially within galaxies has also begun to be investigated, with no clear result as yet. This thesis presents preliminary results from the Fornax3Dsurvey using the MUSE integral field spectrograph. Two techniques for finding the IMF are compared here for the lenticular galaxy FCC167: full spectral fitting, and a more constrained approach focusing on a few key features. While the two methods agree reasonably well on radial variations for the age and abundance parameters in common, the derived IMF shape and its variation within the galaxy differ.Mode of access: World wide web1 online resource (viii, 69 pages) colour illustration