publications

• From Empirical to Physical Model: Direct Fits of Optically Thin Inverse Compton Scattering to Prompt GRB Spectra, P.P. Bordoloi,  S. Mittal, and S. Iyyani, The Astrophysical Journal, 1003, 58 (2026)

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• ​Multivariate time series classification of Fermi-detected gamma-ray transients using convolutional-recurrent neural networks, A. A. John, G. K. Shete, S. Iyyani,  and S. Bej, Machine Learning: Science and Technology, 7, 025046 (2026)

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• Episode-wise spectro-polarimetry of GRB 220107A: Testing the hypothesis of evolving radiation mechanisms, R. Gupta, R. Sonawane, S.Iyyani,  et al. accepted in Astronomy & Astrophysics (2026)

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• Fastest or Significant: A Systematic Framework for Validating Global Minimum Variability Timescale Measurements of Gamma-ray Bursts, S Bala, P Veres, A Goldstein, R Sonawane, R Samanta, S Iyyani, The Astrophysical Journal, 999, 51 (2026). 

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• Extremely luminous optical afterglow of a distant and energetic gamma ray burst GRB230204B, R. Gupta, J. Racusin, …, S. Iyyani, et al. The Astrophysical Journal, 997, 246  (2026).

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• Identification and modelling of optically thin inverse Compton scattering in the prompt emission of GRB131014A, P. P. Bordoloi and S. Iyyani, The Astrophysical Journal, 994, 10 (2025)

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• Spectropolarimetry of GRB 180427A: Evidence for Distinct Emission Sites with Varying Polarization, R. Sonawane, S. Iyyani, S. Gupta, et al.  The Astrophysical Journal, 990,215 (2025).

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• Transients and time domain astrophysics, V. Bhalerao, K. Misra, A. Gadiyara, S. Iyyani, et al. , Journal of Astrophics and Astronomy, 46, 40 (2025)

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• Investigating polarization characteristics of GRB200503A and GRB201009A, D. Sarogi, S. Bala, J. Joshi, S. Iyyani, et al.  Journal of Astrophics and Astronomoy, 46, 38 (2025)

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• Unified theory of negative and positive spectral lags in the gamma ray burst prompt phase due to shear Comptonization from a structured jet, M. K.Vyas, A. Pe’er, and S. Iyyani, The Astrophysical Journal Letters, 975, L29 (2024).

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• A detailed time-resolved and energy-resolved spectra-polarimetric study of bright GRBs detected by AstroSat CZTI in its first year of operation, R. Gupta, S. B. Pandey, … S. Iyyani, et al., The Astrophysical Journal, 972, 166 (2024).

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• Exploring Gamma-Ray Burst Diversity: Clustering analysis of emission characteristics of Fermi and BATSE detected GRBs, N. Mehta and S. Iyyani, The Astrophysical Journal, 88, 69 (2024). 

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• Science with Daksha high energy transients mission, V. Bhalerao; D. Sawant; …; S. Iyyani et al., Experimental Astronomy, 23, 57 (2024).

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• Statistical Analysis of Long GRBs’ prompt emission and X-ray Flares: Multivariate Clustering and Correlations, J, Saji; S, Iyyani and K, Mazde, The Astrophysical Journal Supplementary Series, 269, 2 (2023).

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• Hard X-ray polarization catalog for a five-year sample of gamma-ray bursts using AstroSat CZT Imager, T Chattopadhyay, S Gupta, S Iyyani, et al., The Astrophysical Journal 936 (1), 12 (2022)

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• Recent advances in the study of the prompt emission of gamma-ray bursts, S Iyyani, Journal of Astrophysics and Astronomy 43 (2), 37 (2022)

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• Onset of Particle Acceleration during the Prompt Phase in Gamma-Ray Bursts as Revealed by Synchrotron Emission in GRB 160821A, F Ryde, S Iyyani, B Ahlgren, et al., The Astrophysical Journal Letters 932 (2), L15 (2022)

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• Probing into emission mechanisms of GRB 190530A using time-resolved spectra and polarization studies: synchrotron origin?, R Gupta, S Gupta, T Chattopadhyay, ..., S Iyyani, et al., Monthly Notices of the Royal Astronomical Society 511 (2), 1694-1713 (2022)

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• Sub-MeV spectroscopy with AstroSat-CZT imager for gamma ray bursts, T Chattopadhyay, S Gupta, V Sharma, S Iyyani, et al., Journal of Astrophysics and Astronomy 42 (2), 82 (2021)

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• Discovery and confirmation of the shortest gamma-ray burst from a collapsar, T Ahumada, LP Singer, S Anand, ..., S Iyyani, et al., Nature Astronomy 5 (9), 917-927 (2021)

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• Study of the Prompt Emission of Short Gamma-Ray Bursts Using a Multicolor Blackbody: A Clue to the Viewing Angle, S Iyyani and V Sharma, The Astrophysical Journal Supplement Series 255 (2), 25 (2021)

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• A machine learning approach for GRB detection in AstroSat CZTI data, S Abraham, N Mukund, A Vibhute, V Sharma, S Iyyani, et al., Monthly Notices of the Royal Astronomical Society 504 (2), 3084-3091 (2021)

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• Identifying Black Hole Central Engines in Gamma-Ray Bursts, V Sharma, S Iyyani, D Bhattacharya, The Astrophysical Journal Letters 908 (1), L2 (2021)

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• Spectropolarimetric analysis of prompt emission of GRB 160325A: jet with evolving environment of internal shocks, V Sharma, S Iyyani, D Bhattacharya, et al., Monthly Notices of the Royal Astronomical Society 493 (4), 5218-5232 (2020)

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• Time-varying Polarized Gamma-Rays from GRB 160821A: Evidence for Ordered Magnetic Fields, V Sharma, S Iyyani, D Bhattacharya, et al., The Astrophysical Journal Letters 882 (1), L10 (2019)

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• Observations and physics of prompt emission of gamma ray bursts, S Iyyani, ournal of Astrophysics and Astronomy 39, 1-29 (2018)

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• Violation of Synchrotron Line of Death by the Highly Polarized GRB 160802A, V Chand, T Chattopadhyay, S Iyyani, et al., The Astrophysical Journal 862 (2), 154 (2018)

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• Surprise in simplicity: an unusual spectral evolution of a single pulse GRB 151006A, R Basak, S Iyyani, V Chand, et al., Monthly Notices of the Royal Astronomical Society 472 (1), 891-903 (2017)

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• AstroSat CZT imager observations of GRB 151006A: timing, spectroscopy, and polarization study, AR Rao, V Chand, MK Hingar, S Iyyani, et al., The Astrophysical Journal 833 (1), 86 (2016)

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• Explosive and radio-selected transients: transient astronomy with square kilometre array and its precursors, P Chandra, GC Anupama, KG Arun, S Iyyani, et al., Journal of Astrophysics and Astronomy 37, 1-24 (2016)

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• Synchrotron emission in GRBs observed by Fermi: its limitations and the role of the photosphere, S Iyyani, F Ryde, JM Burgess, A Pe'er and D Bégué, Monthly Notices of the Royal Astronomical Society 456 (2), 2157-2171 (2016)

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• Extremely narrow spectrum of GRB110920A: further evidence for localized, subphotospheric dissipation, S Iyyani, F Ryde, B Ahlgren, JM Burgess, et al., Monthly Notices of the Royal Astronomical Society 450 (2), 1651-1663 (2015)

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• Transparency parameters from relativistically expanding outflows, D Bégué and S Iyyani, The Astrophysical Journal 792 (1), 42 (2014)

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• An observed correlation between thermal and non-thermal emission in gamma-ray bursts, JM Burgess, RD Preece, ..., S Iyyani, et al., The Astrophysical Journal Letters 784 (2), L43 (2014)

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• Time-resolved analysis of Fermi gamma-ray bursts with fast-and slow-cooled synchrotron photon models, M Burgess, RD Preece, ..., S Iyyani, et al., The Astrophysical Journal 784 (1), 17 (2014)

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• The first pulse of the extremely bright GRB 130427A: A test lab for synchrotron shocks, R Preece, JM Burgess, ..., S Iyyani, et al., Science 343 (6166), 51-54 (2014)

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• Variable jet properties in GRB 110721A: time resolved observations of the jet photosphere, S Iyyani, F Ryde, M Axelsson, et al., Monthly Notices of the Royal Astronomical Society 433 (4), 2739-2748 (2013)

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• GRB110721A: an extreme peak energy and signatures of the photosphere, M Axelsson, L Baldini, G Barbiellini, ..., S Iyyani, et al., The Astrophysical journal letters 757 (2), L31 (2012)