collaborators

6 papers

astro-ph.HE2026

A Possible Short-Timescale Optical Quasi-Periodic Oscillation in PKS\,080507 from High-Cadence TESS Observations

Sikandar Akbar, Zahir Shah, Naseer Iqbal +1

We present a timing analysis of the high-cadence optical light curve of the high-redshift flat-spectrum radio quasar PKS\,080507 obtained during \textit{TESS} Sector~34 (MJD~=~5…

astro-ph.HE2026

Broadband Variability Analysis of FSRQ PKS\,0402-362 with Indications of Quasi-Periodic Modulation

Zeeshan Nazir, Sikandar Akbar, Zahir Shah +2

We present a comprehensive temporal and spectral study of the flat-spectrum radio quasar PKS~0402362 using \textit{Fermi}-LAT/Swift-XRT/UVOT observations spanning from MJD 54686…

astro-ph.HE2025

Multiwavelength spectral and temporal analysis of VHE Blazar 1ES 1959+650: Tracing emission mechanisms across flux states

Peer Anjum, Athar A. Dar, Zahir Shah +2

The high-synchrotron-peaked BL Lac object 1ES\,1959+650 exhibited pronounced activity between MJD~60310 -- 60603, including a very high energy (VHE) detection reported by LHAASO. T…

astro-ph.HE2025

Comprehensive Variability Analysis of Blazars Using Fermi Light Curves Across Multiple Timescales

Zahir Shah, Athar A. Dar, Sikandar Akbar +8

In this study, we conducted a systematic analysis of long-term Fermi-LAT γ-ray data for a sample of blazars, including FSRQs, BL\,Lacs, and BCUs, to investigate their -ray var…

astro-ph.HE2025

Statistical Insights into Flux and Photon Index Distributions of VHE FSRQs from Fermi-LAT Observations

Zahoor Malik, Sikandar Akbar, Zahir Shah +8

This study examines the flux and photon index distributions of 11 Very High Energy (VHE) Flat Spectrum Radio Quasars (FSRQs) using over 16 years of Fermi-LAT -ray data. The dis…

astro-ph.HE2025

Signature of hadronic emission in gamma-ray spectrum of B2 1308+326

Athar A. Dar, Zahir shah, Sunder Sahayanathan +3

The Flat Spectrum Radio Quasar (FSRQ) B2\,1308+326 was in its highest -ray flaring state during 60260-60310\,MJD. During this period, the source was detected in very high energ…