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10-day binned light curve of ≈ 15.5 years of Fermi-LAT observation of gravitationally lensed FSRQ PKS 1830−211. The grey region represents the high-flux state, and the white region represents the low-flux state. The light curve is divided into flaring epochs identified using HOP groups, marked by grey patches. HOP groups separated by less than 50 days are combined into flaring states, labeled as F1 to F5 (indicated by horizontal lines). The secondary y-axis (right) shows the detection significance as √ TS. Periods with TS < 9 are represented by upper limits.
Source publication
Variable $\gamma$-ray flares upto minute timescales reflect extreme particle acceleration sites. However, for high-redshift blazars, the detection of such rapid variations remains limited by current telescope sensitivities. Gravitationally lensed blazars serve as powerful tools to probe $\gamma$-ray production zones in distant sources, with time de...
Contexts in source publication
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... the light curve into flaring and quiescent epochs, with consecutive connected BBs above the mean flux baseline referred to as a HOP group. The flare identification code developed by Wagner et al. (2021) differentiates between various HOP groups, leading to the identification of nine HOP groups, represented by grey patches for our source in Fig. 1. The maximum time delay between the source and its lensed counterpart is expected to be approximately 70 days, as suggested by Barnacka et al. (2015). Out of the nine HOP groups represented in Fig. 1, some are less than 70 days apart. These close intervals suggest probable pairs of the source and its echo flare, arising from lensing. ...
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... (2021) differentiates between various HOP groups, leading to the identification of nine HOP groups, represented by grey patches for our source in Fig. 1. The maximum time delay between the source and its lensed counterpart is expected to be approximately 70 days, as suggested by Barnacka et al. (2015). Out of the nine HOP groups represented in Fig. 1, some are less than 70 days apart. These close intervals suggest probable pairs of the source and its echo flare, arising from lensing. Therefore, we group HOP groups that are separated by less than 70 days, leading to five flaring states: F1 (MJD 55450 -55600), F2 (MJD 56063, 56173), F3 (MJD 58363 -58963), F4 (MJD 59063 -59153), and ...
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... days apart. These close intervals suggest probable pairs of the source and its echo flare, arising from lensing. Therefore, we group HOP groups that are separated by less than 70 days, leading to five flaring states: F1 (MJD 55450 -55600), F2 (MJD 56063, 56173), F3 (MJD 58363 -58963), F4 (MJD 59063 -59153), and F5 (MJD 59683 -59943) as shown in Fig. 1. The lag and magnification from these flaring groups are further ...
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... this work, we have used three techniques to estimate the lags in data using (1) autocorrelation Function, (2) double power spectrum, and (3) gaussian process regression. Fig. 1 represents the 5 flaring epochs that have been explored in further work. 1 Time period 2 í µí± í µí±í µí±í µí± 3 í µí± í µí±í µí±>9 /í µí± í µí±¡í µí±í µí±¡ 4 Δí µí± í µí±í µí±í µí± 5 Δí µí± í µí±í µí±í µí±¥ 6 í µí± í µí±í µí±í µí±í µí± 7 í µí± ± í µí± í µí±í µí±í µí± 8 í µí± í µí»½ 9 í µí°¹ í µí±£í µí±í µí± ...
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... HE light curve of PKS 1830-211 appears quite complex, with multiple flaring periods over the quiet states. Fig. 1 shows significant variability in the 10-day binned high-energy (200 MeV -300 GeV) flux over time. This variability is evident from the fluctuating flux levels, with some periods displaying higher fractional variability than others (see Table 1). The flaring periods exhibit dominant pink noise behavior with a PSD power-law index of ...
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... flux state of the source, identified as F3 in this work (Table 1). We use these flaring states to identify dominant emission zones, which should appear as twin pairs of flares separated by a specific time interval for a lensed blazar. The flaring epochs, which are above the mean flux levels, are identified using BBs, indicated by grey patches in Fig. 1. Multiple blocks spaced less than 70 days apart are merged together, resulting in flaring states labeled F1, F2, F3, F4, and ...
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... high-energy spectral properties of the source and the echo flare are consistent within 3í µí¼ (See Fig. 10). A change in the spectral properties would imply a difference in the influence of soft seed photons on í µí»¾−ray photon through í µí»¾ − í µí»¾ absorption on passing through a more luminous region of the lensing galaxy. A ∼ 2.8í µí¼ deviation was observed in the spectral index for flare F21. The identical beta parameters for the four ...
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... the light curve into flaring and quiescent epochs, with consecutive connected BBs above the mean flux baseline referred to as a HOP group. The flare identification code developed by Wagner et al. (2021) differentiates between various HOP groups, leading to the identification of nine HOP groups, represented by grey patches for our source in Fig. 1. The maximum time delay between the source and its lensed counterpart is expected to be approximately 70 days, as suggested by Barnacka et al. (2015). Out of the nine HOP groups represented in Fig. 1, some are less than 70 days apart. These close intervals suggest probable pairs of the source and its echo flare, arising from lensing. ...
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... (2021) differentiates between various HOP groups, leading to the identification of nine HOP groups, represented by grey patches for our source in Fig. 1. The maximum time delay between the source and its lensed counterpart is expected to be approximately 70 days, as suggested by Barnacka et al. (2015). Out of the nine HOP groups represented in Fig. 1, some are less than 70 days apart. These close intervals suggest probable pairs of the source and its echo flare, arising from lensing. Therefore, we group HOP groups that are separated by less than 70 days, leading to five flaring states: F1 (MJD 55450 -55600), F2 (MJD 56063, 56173), F3 (MJD 58363 -58963), F4 (MJD 59063 -59153), and ...
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... days apart. These close intervals suggest probable pairs of the source and its echo flare, arising from lensing. Therefore, we group HOP groups that are separated by less than 70 days, leading to five flaring states: F1 (MJD 55450 -55600), F2 (MJD 56063, 56173), F3 (MJD 58363 -58963), F4 (MJD 59063 -59153), and F5 (MJD 59683 -59943) as shown in Fig. 1. The lag and magnification from these flaring groups are further ...
Context 11
... this work, we have used three techniques to estimate the lags in data using (1) autocorrelation Function, (2) double power spectrum, and (3) gaussian process regression. Fig. 1 represents the 5 flaring epochs that have been explored in further work. 1 Time period 2 í µí± í µí±í µí±í µí± 3 í µí± í µí±í µí±>9 /í µí± í µí±¡í µí±í µí±¡ 4 Δí µí± í µí±í µí±í µí± 5 Δí µí± í µí±í µí±í µí±¥ 6 í µí± í µí±í µí±í µí±í µí± 7 í µí± ± í µí± í µí±í µí±í µí± 8 í µí± í µí»½ 9 í µí°¹ í µí±£í µí±í µí± ...
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... HE light curve of PKS 1830-211 appears quite complex, with multiple flaring periods over the quiet states. Fig. 1 shows significant variability in the 10-day binned high-energy (200 MeV -300 GeV) flux over time. This variability is evident from the fluctuating flux levels, with some periods displaying higher fractional variability than others (see Table 1). The flaring periods exhibit dominant pink noise behavior with a PSD power-law index of ...
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... flux state of the source, identified as F3 in this work (Table 1). We use these flaring states to identify dominant emission zones, which should appear as twin pairs of flares separated by a specific time interval for a lensed blazar. The flaring epochs, which are above the mean flux levels, are identified using BBs, indicated by grey patches in Fig. 1. Multiple blocks spaced less than 70 days apart are merged together, resulting in flaring states labeled F1, F2, F3, F4, and ...
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... high-energy spectral properties of the source and the echo flare are consistent within 3í µí¼ (See Fig. 10). A change in the spectral properties would imply a difference in the influence of soft seed photons on í µí»¾−ray photon through í µí»¾ − í µí»¾ absorption on passing through a more luminous region of the lensing galaxy. A ∼ 2.8í µí¼ deviation was observed in the spectral index for flare F21. The identical beta parameters for the four ...
