An Anomalously Variable Subpopulation of ISP Blazars Irreducible to Standard Observational Biases in the 4LAC-DR3 Catalog (v3: Internal Substructure of C3)

Key Points

• The aim is to analyze a specific subpopulation of ISP blazars to identify distinct variability patterns.
• Secondary GMM analysis conducted within the subgroup C3 (n=22)
• Identification of four sub-groups: C3a, C3b, C3c, and C3d
• Characterization of variability for individual blazars.
• C3a contains 11 high-frequency blazars and shows distinct variability compared to C3c with FracVar values of 1.556 and 1.314 respectively.
• Four distinct sub-groups are identified based on variability patterns in the ISP blazars.
• C3a and C3c indicate two physically distinct variability regimes.