HIDDeN

HIDDeN

HIDDeN - Exploring the Hidden Dusty Nuclei of Galaxies is a 5 years project funded by an Advanced Research Grant from the EU (Grant agreement ID: 789410). The objective is to find and study the most obscured galaxies in the local and distant universe to determine what is hidden behind the veil of dust and what role these extremely obscured objects play in the evolution of galaxies.

Luminous infrared galaxies (LIRGs) emit most of their bolometric luminosity in the far-infrared. They are mainly powered by extreme bursts of star formation and/or Active Galactic Nuclei (AGNs; accreting supermassive black holes (SMBHs)) in their centers. LIRGs are the closest examples of rapid evolution in galaxies and a detailed study of LIRGs is critical for our understanding of the cosmic evolution of galaxies and SMBHs. Centers of some LIRGs are deeply obscured and and difficult to reach at optical, infrared and even X-ray wavelengths. These hidden nuclei therefore represent a largely unexplored phase of the growth of central regions with their SMBHs. The largest growth spurts are suspected to occur when the SMBHs are deeply embedded. Obscured AGNs thus can provide new constraints on the AGN duty cycle, give the full range of environments and astrophysical processes that drive the growth of SMBHs, and help to complete the picture of connections between the host galaxy and SMBH. Many dust embedded AGNs are still to be discovered.

Our Work

In the HIDDeN project we use mm and submm observational methods to reach behind the curtain of dust in the most obscured centers of LIRGs, allowing us to undertake ground-breaking studies of heretofore hidden rapid evolutionary phases of nearby galaxy nuclei. HIDDeN takes advantage of emerging opportunities to address the nature of near-field, and redshift z=1-2, obscured AGNs/starbursts and their associated molecular inflows and outflows in the context of their evolution and the starburst-AGN connection. In addition to using state-of-the art mm/submm facilities such as ALMA, we also important radi-wavelength facilities such as VLBI, Merlin and the VLA. We also include shorter wavelength observations at optical facilities (inluding MUSE) and infrared (upcoming JWST) and X-ray facilities (e.g. NuSTAR). We combine these intruments to address four interconnected goals: A. Probing the Dusty Interiors of Compact Obscured Nuclei (CONs), B. The cold winds of change - Molecular Outflows from LIRGs and AGNs, C. The Co-Evolution of Starbursts and AGNs and D. Are there hidden CONs at z=1-2?

Further Information

The HIDDeN project is led by Professor Susanne Aalto, Chalmers University of Technology, Sweden. [Here we will add information of people in the HIDDeN project, links to publications and our main observing programmes. ]