The tight correlation between total galaxy stellar mass and star formation rate (SFR) has become known as the star forming main sequence. Using ∼ 487,000 spaxels from galaxies observed as part of the Sloan Digital Sky Survey Mapping Galaxies at Apache Point Observatory (MaNGA) survey, we confirm previous results that a correlation also exists between the surface densities of star formation (Σ SFR ) and stellar mass (Σ ) on kpc scales, representing a 'resolved' main sequence. Using a new metric (∆Σ SFR ), which measures the relative enhancement or deficit of star formation on a spaxel-by-spaxel basis relative to the resolved main sequence, we investigate the SFR profiles of 864 galaxies as a function of their position relative to the global star forming main sequence (∆SFR). For galaxies above the global main sequence (positive ∆SFR) ∆Σ SFR is elevated throughout the galaxy, but the greatest enhancement in star formation occurs at small radii (< 3 kpc, or 0.5 R e ). Moreover, galaxies that are at least a factor of three above the main sequence show diluted gas phase metallicities out to 2 R e , indicative of metal-poor gas inflows accompanying the starbursts. For quiescent/passive galaxies that lie at least a factor of 10 below the star forming main sequence there is an analogous deficit of star formation throughout the galaxy with the lowest values of ∆Σ SFR in the central 3 kpc. Our results are in qualitative agreement with the 'compaction' scenario in which a central starburst leads to mass growth in the bulge and may ultimately precede galactic quenching from the inside-out.

Large galaxy surveys have demonstrated that galaxy-galaxy mergers can dramatically change the morphologies, star formation rates (SFRs) and metallicities of their constituents. However, most statistical studies have been limited to the measurement of global quantities, through large fibres or integrated colours. In this work, we present the first statistically significant study of spatially resolved star formation and metallicity profiles using integral field spectroscopy, using a sample of ∼20,000 spaxels in 36 visually selected post-merger galaxies from the Mapping Nearby Galaxies with Apache Point Observatory (MaNGA) survey. By measuring offsets from SFR and metallicity scaling relations on a spaxel-by-spaxel basis, we are able to quantify where in the galaxy these properties are most affected by the interaction. We find that the SFR enhancements are generally centrally peaked, by a factor of 2.5 on average, in agreement with predictions from simulations. However, there is considerable variation in the SFR behaviour in the galactic outskirts, where both enhancement and suppression are seen. The median SFR remains enhanced by 0.1 dex out to at least 1.9 Re. The metallicity is also affected out to these large radii, typically showing a suppression of ∼ −0.04 dex.

Using gold nanoparticles coated on ITO as a polarization-sensitive photodetector, we intend to locate the source of hot electron emission in rectenna. This plasmonic photodetector is polarisation sensitive and has the potential to achieve high efficiency across a wide range of frequencies.