Unveiling the Multi-wavelength connection from Correlations of astronomical and astrometric/geodetic data of AGN sources in the K-band Celestial Reference Frame (CRF) Catalogue.

Active galactic nuclei (AGN) constitute the largest population in the gamma-ray sky, and host the most extreme environments capable of accelerating particles that radiate in the entire electromagnetic spectrum, while also launching stable mega-parsec (Mpc) scale jets. However, understanding the nature and location of their fast variability emission zone remains a challenge, necessitating population studies to better grasp the characteristics of these intricate objects.

The K-band Celestial Reference Frame (CRF) catalogue project recently published 5078 high-resolution Very Long Baseline Interferometry (VLBI) images, capturing 731 AGNs across 27 epochs. Leveraging this unique and incredibly extensive dataset, our study integrated VLBI flux-density time-series and images, complemented by gamma-ray data from the space-based Fermi Large Area Telescope (Fermi-LAT, 20 MeV up to 1 TeV).  

We focused on investigating the multi-wavelength connections for 43 AGNs carefully selected from the K-band CRF catalogue. Our analysis delved into the intricate relationships among radio and gamma-ray, and positional time-series data from astronomical and astrometric/geodetic observations. Preliminary results suggest the existence of correlations between the positional offsets and gamma-ray data, as well as between radio and gamma-ray bands in select AGNs. Additionally, intriguing patterns of long-term variability among the chosen AGNs were also uncovered, shedding light on the dynamic interplay between radio and gamma-ray emissions.

These findings offer crucial insights into the underlying physical processes, contributing to a deeper understanding of the astrophysical mechanisms governing AGN behavior. Our work represents an important step forward in our ongoing pursuit to comprehend the complex nature of AGNs.