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ZTF Monitoring of $γ-$ray emitting Narrow Line Seyfert 1 Galaxies

Aman Kumar, Suvas Chandra Chaudhary, Raj Prince, Brian van Soelen, I. P. van der Westhuizen

Abstract

The $γ$-ray-emitting narrow-line Seyfert-I ($γ$-NLSy1) are among the most interesting systems for studying disk-jet coupling. The soft X-ray properties of these systems suggest the presence of a disc component, which peaks in the optical/UV regime, in addition to the active jet. In this work, we investigate the optical emission from $γ$-NLSy1 using long-term Zwicky Transient Facility (ZTF) observations and discussed in the context of blazars. We have reported the long-term flux and color variability in the g- and r-bands. The fractional variability ($F_{\rm var}$) goes as high as 72\%, with a mean value of 23\%, while the amplitude of variability ($ψ$) values range from 0.24 to 3.20, which is consistent with the long-term Swift-UVOT variability studies. The color-magnitude diagrams exhibit an RWB or BWB trend similar to that of blazars. The $t_{\rm var}$ suggests an emitting region size of $10^{15-17}$ cm, aligned with emissions coming from the inner accretion disk or base of the jet. The PSD analysis using both DRW and CARMA modeling exhibits a characteristic break timescale of a few days to hundreds of days, which is likely linked to fundamental physical timescales in the system, such as thermal or viscous timescales in the accretion disk or timescales for acceleration and energy dissipation in the jet. The existence of these timescales acts as another signature of the disc-jet connection. These time scales are correlated with black hole mass, and the relation is consistent with previous studies.

ZTF Monitoring of $γ-$ray emitting Narrow Line Seyfert 1 Galaxies

Abstract

The -ray-emitting narrow-line Seyfert-I (-NLSy1) are among the most interesting systems for studying disk-jet coupling. The soft X-ray properties of these systems suggest the presence of a disc component, which peaks in the optical/UV regime, in addition to the active jet. In this work, we investigate the optical emission from -NLSy1 using long-term Zwicky Transient Facility (ZTF) observations and discussed in the context of blazars. We have reported the long-term flux and color variability in the g- and r-bands. The fractional variability () goes as high as 72\%, with a mean value of 23\%, while the amplitude of variability () values range from 0.24 to 3.20, which is consistent with the long-term Swift-UVOT variability studies. The color-magnitude diagrams exhibit an RWB or BWB trend similar to that of blazars. The suggests an emitting region size of cm, aligned with emissions coming from the inner accretion disk or base of the jet. The PSD analysis using both DRW and CARMA modeling exhibits a characteristic break timescale of a few days to hundreds of days, which is likely linked to fundamental physical timescales in the system, such as thermal or viscous timescales in the accretion disk or timescales for acceleration and energy dissipation in the jet. The existence of these timescales acts as another signature of the disc-jet connection. These time scales are correlated with black hole mass, and the relation is consistent with previous studies.
Paper Structure (13 sections, 18 equations, 25 figures, 4 tables)

This paper contains 13 sections, 18 equations, 25 figures, 4 tables.

Table of Contents

  1. Introduction
  2. SAMPLE SELECTION and ZTF DATA COLLECTION
  3. Analysis Techniques and Results
  4. Flux Variability
  5. Color Variability
  6. Discrete Correlation Function
  7. Flux Distribution
  8. Flux-RMS Relationship
  9. CARMA Modeling
  10. Discussion and Interpretation
  11. Conclusions
  12. Individual Plots
  13. Lightcurves, Color Magnitude Diagrams, Flux histograms, PSD, Simulated LCs.

Figures (25)

  • Figure 1: ZTF lightcurve for $\gamma$-NLSY1 J142105+385522 in $g$ and $r$ band. Other lightcurves are shown in Appendix \ref{['sec:Ind_plots']}.
  • Figure 2: Colour Magnitude Plot of J142105+385522. Other colour-magnitude plots are shown in Appendix \ref{['sec:Ind_plots']}.
  • Figure 3: An example DCF for two sources is shown: Other DCFs are shown in Appendix \ref{['sec:Ind_plots']}.
  • Figure 4: Flux Distribution of object J142105+385522. Other distributions are shown in Appendix \ref{['sec:Ind_plots']}.
  • Figure 5: RMS vs Mean Magnitude relation for all the sources in R and G band.
  • ...and 20 more figures