Multiwavelength correlation studies in the era of CTAO

Abstract

Correlations between various multiwavelength (MWL) bands are an intermittent feature in blazar light curves; that is, they are observed in some instances but not in others. With the CTAO we will obtain detailed very-high-energy (VHE) gamma-ray light curves for many sources also during their low states, enabling detailed MWL correlation studies. For two blazars, the HBL Mrk\,421 and the FSRQ PKS\,1510-089, the long-term X-ray and optical light curves are used to induce variations in input parameters of the lepto-hadronic one-zone code OneHaLe. We show light curves in the CTA energy range for three different energy thresholds. The results are: 1) the presence of relativistic protons has a significant effect on the correlation of the light curves as the emerging pair cascade prolongs flaring states at the highest energies; and 2) comparison of the theoretical light curves with existing VHE gamma-ray data shows that both leptonic and hadronic models can only partially reproduce the data.