My Research

2175Å UV bump illustration

The 2175Å UV Bump at High Redshift

In this paper, we identified a bright galaxy at z=7.1, with a strong 2175Å UV bump feature in its rest-UV spectrum, through observations taken as part of the NIRSpec Wide GTO survey.

The presence of the UV bump feature at such early times indicates rapid evolution of dust properties within the first billion years of cosmic time. To investigate the origin of the dust responsible for the UV bump, we carried out resolved SED fitting, suggesting that existing (large) dust grains are likely being rapidly reprocessed in the ISM, producing the small carbonaceous grains responsible for the UV bump feature. Find out more →

Example Sersic profile fits

The Size and Shape Evolution of Galaxies with the James Webb Space Telescope

In this paper, we present a morphological analysis of 1395 galaxies at 0.5 ≤ z ≲ 8 with stellar masses log (M*/M⊙) > 9., using public JWST NIRCam data within the CEERS field, overlapping with the CANDELS EGS observations. We utilise surface brightness fitting with GALFIT to fit single Sérsic models to the rest-frame optical profile of galaxies.

We find that galaxies become progressively smaller with increasing redshift, and that the majority of massive galaxies at high redshift are are described by low Sérsic indices. Find out more →

Successful Proposals

Constraining Dust Formation at Cosmic Dawn with Luminous UV Bump Galaxies

PI, JWST NIRSpec IFU
Observing time: 19 hours

The 2175Å UV bump as a signpost of NIRCam dark star formation

PI, NOEMA interferometer
Observing time: 25 hours

Unveiling dust build up in a 'UV bump' galaxy at z=7.1 with JWST+NOEMA

Co-PI, NOEMA interferometer
Observing time: 16 hours