First-authored, refereed papers of Rajkumar Hajra, ordered by citations

A list of first-authored, refereed publications of Rajkumar Hajra, derived from the SAO/NASA Astrophysics Data System (ADS) and ordered by the numbers of citations.

Orcid ID: 0000-0003-0447-1531

101	Solar cycle dependence of High-Intensity Long-Duration Continuous AE Activity (HILDCAA) events, relativistic electron predictors? Hajra, R., Echer, E., Tsurutani, B. T. & Gonzalez, W. D., 2013, Journal of Geophysical Research (Space Physics), 118, 5626
68	Relativistic (e > 0.6, > 2.0, and > 4.0 MeV) Electron Acceleration at Geosynchronous Orbit during High-intensity, Long-duration, Continuous AE Activity (HILDCAA) Events Hajra, Rajkumar, Tsurutani, Bruce T., Echer, Ezequiel, Gonzalez, Walter D. & Santolik, Ondrej, 2015, ApJ, 799, 39
58	Relativistic electron acceleration during high-intensity, long-duration, continuous AE activity (HILDCAA) events: Solar cycle phase dependences Hajra, Rajkumar, Tsurutani, Bruce T., Echer, Ezequiel & Gonzalez, Walter D., 2014, Geophysical Research Letters, 41, 1876
55	Supersubstorms (SML < -2500 nT): Magnetic storm and solar cycle dependences Hajra, Rajkumar, Tsurutani, Bruce T., Echer, Ezequiel, Gonzalez, Walter D. & Gjerloev, Jesper W., 2016, Journal of Geophysical Research (Space Physics), 121, 7805
48	Solar wind-magnetosphere energy coupling efficiency and partitioning: HILDCAAs and preceding CIR storms during solar cycle 23 Hajra, Rajkumar, Echer, Ezequiel, Tsurutani, Bruce T. & Gonzalez, Walter D., 2014, Journal of Geophysical Research (Space Physics), 119, 2675
44	Interplanetary Shocks Inducing Magnetospheric Supersubstorms (SML < -2500 nT): Unusual Auroral Morphologies and Energy Flow Hajra, Rajkumar & Tsurutani, Bruce T., 2018, ApJ, 858, 123
44	The Complex Space Weather Events of 2017 September Hajra, Rajkumar, Tsurutani, Bruce T. & Lakhina, Gurbax S., 2020, ApJ, 899, 3
38	Interplanetary Causes and Impacts of the 2024 May Superstorm on the Geosphere: An Overview Hajra, Rajkumar, Tsurutani, Bruce Tsatnam, Lakhina, Gurbax Singh, Lu, Quanming & Du, Aimin, 2024, ApJ, 974, 264
31	Superposed epoch analyses of HILDCAAs and their interplanetary drivers: Solar cycle and seasonal dependences Hajra, Rajkumar, Echer, Ezequiel, Tsurutani, Bruce T. & Gonzalez, Walter D., 2014, Journal of Atmospheric and Solar-Terrestrial Physics, 121, 24
30	Relativistic electron acceleration during HILDCAA events: are precursor CIR magnetic storms important? Hajra, Rajkumar, Tsurutani, Bruce T., Echer, Ezequiel, Gonzalez, Walter D., Brum, Christiano Garnett Marques, Vieira, Luis Eduardo Antunes & Santolik, Ondrej, 2015, Earth, Planets and Space, 67, 109
30	An empirical model of ionospheric total electron content (TEC) near the crest of the equatorial ionization anomaly (EIA) Hajra, Rajkumar, Chakraborty, Shyamal Kumar, Tsurutani, Bruce T., DasGupta, Ashish, Echer, Ezequiel, Brum, Christiano G. M., Gonzalez, Walter D. & Sobral, José Humberto Andrade, 2016, Journal of Space Weather and Space Climate, 6, A29
29	Cometary plasma response to interplanetary corotating interaction regions during 2016 June-September: a quantitative study by the Rosetta Plasma Consortium Hajra, Rajkumar, Henri, Pierre, Myllys, Minna, Héritier, Kevin L., Galand, Marina, Simon Wedlund, Cyril, Breuillard, Hugo, Behar, Etienne, Edberg, Niklas J. T., Goetz, Charlotte, Nilsson, Hans, Eriksson, Anders I., Goldstein, Raymond, Tsurutani, Bruce T., Moré, Jerome, Vallières, Xavier & Wattieaux, Gaetan, 2018, MNRAS, 480, 4544
28	Corotating Interaction Regions during Solar Cycle 24: A Study on Characteristics and Geoeffectiveness Hajra, Rajkumar & Sunny, Jibin V., 2022, Solar Physics, 297, 30
27	Impact of a cometary outburst on its ionosphere. Rosetta Plasma Consortium observations of the outburst exhibited by comet 67P/Churyumov-Gerasimenko on 19 February 2016 Hajra, R., Henri, P., Vallières, X., Galand, M., Héritier, K., Eriksson, A. I., Odelstad, E., Edberg, N. J. T., Burch, J. L., Broiles, T., Goldstein, R., Glassmeier, K. H., Richter, I., Goetz, C., Tsurutani, B. T., Nilsson, H., Altwegg, K. & Rubin, M., 2017, A&A, 607, A34
27	Weakest Solar Cycle of the Space Age: A Study on Solar Wind-Magnetosphere Energy Coupling and Geomagnetic Activity Hajra, Rajkumar, 2021, Solar Physics, 296, 33
24	Long Term Variations of the Geomagnetic Activity: A Comparison Between the Strong and Weak Solar Activity Cycles and Implications for the Space Climate Hajra, Rajkumar, Marques de Souza Franco, Adriane, Echer, Ezequiel & José Alves Bolzan, Mauricio, 2021, Journal of Geophysical Research (Space Physics), 126, e28695
22	Near-Earth Sub-Alfvénic Solar Winds: Interplanetary Origins and Geomagnetic Impacts Hajra, Rajkumar & Tsurutani, Bruce T., 2022, ApJ, 926, 135
19	Dynamic unmagnetized plasma in the diamagnetic cavity around comet 67P/Churyumov-Gerasimenko Hajra, Rajkumar, Henri, Pierre, Vallières, Xavier, Moré, Jerome, Gilet, Nicolas, Wattieaux, Gaetan, Goetz, Charlotte, Richter, Ingo, Tsurutani, Bruce T., Gunell, Herbert, Nilsson, Hans, Eriksson, Anders I., Nemeth, Zoltan, Burch, James L. & Rubin, Martin, 2018, MNRAS, 475, 4140
17	The April 2023 SYM-H = −233 nT Geomagnetic Storm: A Classical Event Hajra, Rajkumar, Tsurutani, Bruce Tsatnam, Lu, Quanming, Horne, Richard B., Lakhina, Gurbax Singh, Yang, Xu, Henri, Pierre, Du, Aimin, Gao, Xingliang, Wang, Rongsheng & Lu, San, 2024, Journal of Geophysical Research (Space Physics), 129, e2024JA032986
14	High-speed solar wind stream effects on the topside ionosphere over Arecibo: A case study during solar minimum Hajra, Rajkumar, Tsurutani, Bruce T., Brum, Christiano G. M. & Echer, Ezequiel, 2017, Geophysical Research Letters, 44, 7607
13	Variation of the Interplanetary Shocks in the Inner Heliosphere Hajra, Rajkumar, 2021, ApJ, 917, 91
13	Intense, Long-Duration Geomagnetically Induced Currents (GICs) Caused by Intense Substorm Clusters Hajra, Rajkumar, 2022, Space Weather, 20, e2021SW002937
11	Electrodynamical control of the ambient ionization near the equatorial anomaly crest in the Indian zone during counter electrojet days Hajra, R., Chakraborty, S. K. & Paul, A., 2009, Radio Science, 44, RS3009
10	Intense Geomagnetically Induced Currents (GICs): Association with Solar and Geomagnetic Activities Hajra, Rajkumar, 2022, Solar Physics, 297, 14
10	Interplanetary Sheaths and Corotating Interaction Regions: A Comparative Statistical Study on Their Characteristics and Geoeffectiveness Hajra, Rajkumar, Sunny, Jibin V., Babu, Megha & Nair, Archana Giri, 2022, Solar Physics, 297, 97
10	Interplanetary Shocks between 0.3 and 1.0 au: Helios 1 and 2 Observations Hajra, Rajkumar, Tsurutani, Bruce T., Lakhina, Gurbax S., Lu, Quanming, Du, Aimin & Shan, Lican, 2023, ApJ, 951, 75
9	September 2017 Space-Weather Events: A Study on Magnetic Reconnection and Geoeffectiveness Hajra, Rajkumar, 2021, Solar Physics, 296, 50
9	Evolution of equatorial irregularities under varying electrodynamical conditions: A multitechnique case study from Indian longitude zone Hajra, R., Chakraborty, S. K., Mazumdar, S. & Alex, S., 2012, Journal of Geophysical Research (Space Physics), 117, A08331
6	Earth's magnetotail variability during supersubstorms (SSSs): A study on solar wind-magnetosphere-ionosphere coupling Hajra, Rajkumar, Echer, Ezequiel, Franco, Adriane Marques de Souza & Bolzan, Mauricio José Alves, 2023, Advances in Space Research, 72, 1208
6	Ultra-relativistic Electron Acceleration during High-intensity Long-duration Continuous Auroral Electrojet Activity Events Hajra, Rajkumar, Tsurutani, Bruce T., Lu, Quanming, Lakhina, Gurbax S., Du, Aimin, Echer, Ezequiel, Franco, Adriane M. S., Bolzan, Mauricio J. A. & Gao, Xinliang, 2024, ApJ, 965, 146
6	Seasonal dependence of the Earth's radiation belt ─ new insights Hajra, Rajkumar, 2021, Annales Geophysicae, 39, 181
5	Near-Earth High-Speed and Slow Solar Winds: A Statistical Study on Their Characteristics and Geomagnetic Impacts Hajra, Rajkumar, 2023, Solar Physics, 298, 53
4	Ionospheric effects near the magnetic equator and the anomaly crest of the Indian longitude zone during a large number of intense geomagnetic storms Hajra, R., Chakraborty, S. K. & Dasgupta, A., 2010, Journal of Atmospheric and Solar-Terrestrial Physics, 72, 1299
4	Equatorial ionospheric responses in relation to the occurrence of main phase of intense geomagnetic storms in the local dusk sector Hajra, R. & Chakraborty, S. K., 2011, Journal of Atmospheric and Solar-Terrestrial Physics, 73, 760
3	Ionospheric total electron content of comet 67P/Churyumov-Gerasimenko Hajra, Rajkumar, Henri, Pierre, Vallières, Xavier, Galand, Marina, Rubin, Martin, Tsurutani, Bruce T., Gilet, Nicolas, Bucciantini, Luca & Nemeth, Zoltan, 2020, A&A, 635, A51
2	Solar Cycle and Seasonal Dependences of Field-Aligned Currents Hajra, Rajkumar, Tsurutani, Bruce T., Lu, Quanming, Du, Aimin, Lu, San & Echer, Ezequiel, 2025, Space Weather, 23, e2025SW004441
1	Extreme Rarefaction of Solar Wind: A Study on Origin and Characteristics Using Ulysses Observations Hajra, Rajkumar, Tsurutani, Bruce T., Lu, Quanming, Shan, Lican, Du, Aimin, Wang, Rongsheng, Lu, San & Gao, Xinliang, 2023, ApJ, 955, 120
0	Supersubstorms during the May 2024 superstorm Hajra, Rajkumar, Tsurutani, Bruce T., Lu, Quanming, Du, Aimin & Lakhina, Gurbax S., 2025, Journal of Space Weather and Space Climate, 15, 51
0	Field-Aligned Currents During High-Intensity Long-Duration Continuous Auroral Electrojet Activity Events: A Statistical Study Hajra, Rajkumar, Tsurutani, Bruce T., Lu, Quanming, Du, Aimin, Lu, San & Gao, Xinliang, 2025, Space Weather, 23, e2025SW004353
0	Field-Aligned Currents During High-Intensity Long-Duration Continuous Auroral Electrojet Activity Events: Seasonal Dependences Hajra, Rajkumar, Tsurutani, Bruce T., Lu, Quanming & Du, Aimin, 2025, Space Weather, 23, e2025SW004354