The Milky Way experienced several merger events which left their imprints on the stellar halo. In particular, it is known that a major merger happened during the Galaxy’s first Gyrs and, likely, perturbed its disc-shape structure. In order to fully understand the effects of such an event, we need to know the chemical and dynamical characteristics of the young Milky Way, i.e. before the major m...
I will present an overview of the JWST NIRCam wide-field slitless spectroscopy (WFSS). This observing mode is highly efficient in spectroscopically confirming galaxies in the Epoch of Reionization through rest-frame optical emission lines (e.g., [OIII] and Hα). With NIRCam WFSS, galaxies at z>6 can be easily detected and confirmed with ~10-min integration. The following studies will be highlig...
In this talk I will discuss the geometry, structure and morphological transformation of star-forming and quiescent galaxies from the peak of cosmic star formation to the present day. Resolved observations from multiple wavelengths and tracers enable us to reconstruct where stars form within galaxies and how stellar distributions are assembled, while simultaneously revealing insights into the e...
One commonly accepted idea for the origin of the large-scale structure in the Universe is that the minute quantum fluctuations were stretched to macroscopic scales as a consequence of nearly exponential expansion of spacetime during the “cosmic inflation”. Cosmic inflation predicts primordial density fluctuations that are consistent with the observed CMB temperature fluctuations. It also pred...
Dark matter — established via various cosmological and astronomical observations — is a significant constituent of our Universe and remains one of the most outstanding mysteries of modern physics. The mass range of potential dark matter candidates covers more than 30 orders of magnitude. In the past, researchers have primarily focused on searching for GeV-TeV dark matter (WIMP) via nuclear re...