Supervisory team: David Pinfield, Bartek Gauza, Hugh Jones
Proper motion is the angular velocity at which astronomical objects move across the sky, and can be used to select local or fast-moving objects of interest. However, such objects can also have extreme colours and be much fainter in one wave-band compared to another. So in the fainter wave-band an object may only be detectable in very deep "image stacks" (constructed by adding together many individual images observed over several years). In such “image stacks” high proper motion objects may appear as extended sources at offset positions (due to their movement between individual images in the stack), and a very high proper motion object may even manifest as an apparent "trail" of objects in an image stack.
In this project you will combine deep optical and near infrared/infrared survey data from ground/space-based surveys to search for high proper motion brown dwarfs. Brown dwarfs have extremely colours (e.g optical-NIR or NIR-IR) and can have high proper motion if they are nearby or are members of the thick-disk/halo kinematic populations. You will develop a method to search for brown dwarfs that are point-like objects in one survey but are extended (or forming a trail) in deep-stack survey/s. And you will then explore the nature of these objects using colour/magnitude and proper motions to assess spectra type, distance and age (from e.g. kinematic group membership, companionship, and moving group membership).