Intense, compact, star-forming galaxies are rare in the local Universe butubiquitous at high redshift. We interpret the 0.1-22 um spectral energydistributions (SED) of a sample of 180 galaxies at 0.05<z<0.25 selected forextremely high surface densities of inferred star formation in the ultraviolet.By comparison with well-established stellar population synthesis models we findthat our sample comprises young (~ 60 - 400 Myrs), moderate mass (~ $6\times10^9$ Msun) star-forming galaxies with little dust extinction (mean stellarcontinuum extinction $E_\mathrm{cont}$(B-V) ~ 0.1) and find star formationrates of a few tens of Solar masses per year. We use our inferred masses todetermine a mean specific star formation rate for this sample of ~ $10^{-9}$yr$^{-1}$, and compare this to the specific star formation rates in distantLyman break galaxies (LBGs), and in other low redshift populations. We concludethat our sample's characteristics overlap significantly with those of the z~5LBG population, making ours the first local analogue population well tuned tomatch those high redshift galaxies. We consider implications for the origin andevolution of early galaxies.

NGC 1808 is a nearby barred starburst galaxy with an outflow from the nuclearregion. To study the inflow and outflow processes related to star formation anddynamical evolution of the galaxy, we have carried out \(^{12}\)CO (\(J=1-0\))mapping observations of the central \(r\sim4\) kpc of NGC 1808 using theAtacama Large Millimeter/submillimeter Array (ALMA). Four distinct componentsof molecular gas are revealed at high spatial resolution of 2\arcsec(\(\sim100\) pc): (1) a compact (\(r<200\) pc) circumnuclear disk (CND), (2)\(r\sim500\) pc ring, (3) gas-rich galactic bar, and (4) spiral arms. Basicgeometric and kinematic parameters are derived for the central 1-kpc regionusing tilted-ring modeling. The derived rotation curve reveals multiple masscomponents that include (1) a stellar bulge, (2) nuclear bar and molecular CND,and (3) unresolved massive (\(\sim10^7~M_\sun\)) core. Two systemic velocities,998 km s\(^{-1}\) for the CND and 964 km s\(^{-1}\) for the 500-pc ring, arerevealed, indicating a kinematic offset. The pattern speed of the primary bar,derived by using a cloud-orbit model, is \(56\pm11\) km s\(^{-1}\)kpc\(^{-1}\). Non-circular motions are detected associated with a nuclearspiral pattern and outflow in the central 1-kpc region. The ratio of the massoutflow rate to the star formation rate is \(\dot{M}_\mathrm{out}/SFR\sim0.2\)in the case of optically thin CO (1-0) emission in the outflow, suggesting lowefficiency of star formation quenching.

We present the first detailed integral field spectroscopy study of ninecentral void galaxies with M*>10^10 Msun using the Wide Field Spectrograph(WiFeS) to determine how a range of assembly histories manifest themselves inthe current day Universe. While the majority of these galaxies are evolvingsecularly, we find a range of morphologies, merger histories and stellarpopulation distributions, though similarly low Halpha-derived star formationrates (<1 Msun/yr). Two of our nine galaxies host AGNs, and two have kinematicdisruptions to their gas that are not seen in their stellar component. Mostmassive void galaxies are red and discy, which we attribute to a lack of majormergers. Some have disturbed morphologies and may be in the process of evolvingto early-type thanks to ongoing minor mergers at present times, likely fed bytendrils leading off filaments. The diversity in our small galaxy sample,despite being of similar mass and environment means that these galaxies arestill assembling at present day, with minor mergers playing an important rolein their evolution. We compare our sample to a mass and magnitude-matched sample of fieldgalaxies, using data from the Sydney-AAO Multi-object Integral fieldspectrograph (SAMI) galaxy survey. We find that despite environmentaldifferences, galaxies of mass M*>10^10 Msun have similarly low star formationrates (<3 Msun/yr). The lack of distinction between the star formation rates ofthe void and field environments points to quenching of massive galaxies being alargely mass-related effect.