Astrophysical Research

Home Page My Research Works & Pulbications Data Python Utils Many Stuff $\kappa$urvature

My Research (need to add some things)


Galaxy Morphology (need to add a lot of things)

Hubble-De Vaucouleurs Diagram. Source: Wikipedia. Credits: Antonio Ciccolella / M. De Leo


Galaxy morphology is one of the keys to unveil how galaxies formed and evolved across different cosmic times and environments in the Universe. Therefore, the understanding of the underling structure of galaxies in a precise way is a crucial information that can be used for such studies and galaxy morphological classification.

In a recent paper (Lucatelli and Ferrari, $2019$) we have introduced the curvature of the brightness profile $\widetilde{\varkappa}(R)$ for galaxy structural analysis. In this research we use the curvature as a new non-parametric approach to identify different structural components in a galaxy, such as bulges, bars, rings, disks and spiral arms, as well distinguish ellipticals from spirals and lenticular galaxies.

In sequence of that work (the current research) we show that the curvature can be suitable and automated for the identification of galaxy subcomponents. This method can constrain the scale length of each component thus assist or validate some standard techniques of structural analysis, such as the profile fitting of multiple parametric functions (e.g. Sérsic). Furthermore, after all image processing procedures (filtering, cleaning, etc), the curvature demonstrated to be little affected by image resolution and signal-to-noise ratio, therefore it may be used for galaxies in a high redshift regime.

Our conclusions are that local peaks in the curvature profile indicates the transition regions of different components and the shape of curvature in that regions is intrinsically related to specific structural components. Thus the overall shape of the curvature over all galaxy radius give us a hint of its morphology.