| Abstract : | In the paradigm of hierarchical structure formation, the galaxies are thought to form and evolve inside a potential well environment (halos) of 'collisionless' and 'only gravitationally interacting' form of matter. These dark halos have formed at the peaks of initial density fluctuations due to gravitational instability and as observations have revealed, are the sites of most of the galaxy formation and evolution.
Estimating the presence of these dark structures of halos by using available galaxy surveys itself is an important and challenging task. This information can then be used to find out the connection between the galaxy and halo properties.
Our current understanding of the structure formation and evolution is driven by simulations. At large scales the full hydrodynamic simulations are not feasible due to computational cost. However using 'the connection' (scaling relations) between galaxy properties like for example, 'star formation rate/ stellar mass' versus the 'halo mass', semi-analytical models of structure formation can constrain the effectiveness of physical processes as a function of redshift, thus bypassing the need of full simulation from scratch.
In our work,
to estimate the masses of dark matter halos which host - (the lens galaxies) the photometric galaxies from HSC survey's wide layer, we employ the technique of measurement of 'weak gravitational lensing' signals. Weak lensing being purely gravitational phenomena, directly and fully probes the total matter content responsible for lensing of the background source galaxies. Thus we are able to probe this matter content associated with lens galaxies responsible for lensing.
We show the halo-mass vs stellar mass relation as our concluding scaling relation from low to high redshift bins of lens galaxies further split into bins of stellar masses, and in doing so we represent the power of wide layer of HSC survey for statistical studies like weak lensing. |
