One Year of ASPEX-STEPS Operation: Characteristic Features, Observations and Science Potential

Jacob Sebastian; Bijoy Dalal; Aakash Gupta; Shiv Kumar Goyal; Dibyendu Chakrabarty; Santosh V. Vadawale; M. Shanmugam; Neeraj Kumar Tiwari; Arpit R. Patel; Aveek Sarkar; Aaditya Sarda; Tinkal Ladiya; Prashant Kumar; Manan S. Shah; Abhishek Kumar; Shivam Parashar; Pranav R. Adhyaru; Hiteshkumar L. Adalja; Piyush Sharma; Abhishek J. Verma; Nishant Singh; Sushil Kumar; Deepak Kumar Painkra; Swaroop B. Banerjee; K. P. Subramaniam; Bhas Bapat; M. B. Dadhania; P. Janardhan; Anil Bhardwaj

arXiv · 2507.18117

One Year of ASPEX-STEPS Operation: Characteristic Features, Observations and Science Potential

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Abstract

The SupraThermal and Energetic Particle Spectrometer (STEPS), a subsystem of the Aditya Solar wind Particle EXperiment (ASPEX) onboard India's Aditya-L1 satellite, is designed to study different aspects of energetic particles in the interplanetary medium from the Sun-Earth L1 point using six detector units oriented in different directions. This article presents details of the one-year operation (08 January 2024 - 28 February 2025) of the AL1-ASPEX-STEPS after the insertion of the satellite into the final halo orbit around the L1 point with emphasis on performance, science observations, and scientific potentials. Four out of six AL1-ASPEX-STEPS units exhibit a stable detector response throughout the observation period, confirming operational robustness. This work also includes the temporal variation of particle fluxes, spectra of ions during selected quiet times and transient events, and cross-comparisons with existing instruments at the L1 point. A strong correlation (with coefficient of determination, R2 ~ 0.9) is observed in the cross-comparison study, establishing the reliability of the AL1- ASPEX-STEPS observations. AL1-ASPEX-STEPS also captures different forms of energetic ion spectra similar to those observed by previous missions. These results underscore the instrument's potential to contribute significantly to the study of energetic particle acceleration, transport, and long-term space weather monitoring from the Sun-Earth L1 vantage point.

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Jacob Sebastian, Bijoy Dalal, Aakash Gupta, Shiv Kumar Goyal, Dibyendu Chakrabarty, Santosh V. Vadawale, M. Shanmugam, Neeraj Kumar Tiwari, Arpit R. Patel, Aveek Sarkar, Aaditya Sarda, Tinkal Ladiya, Prashant Kumar, Manan S. Shah, Abhishek Kumar, Shivam Parashar, Pranav R. Adhyaru, Hiteshkumar L. Adalja, Piyush Sharma, Abhishek J. Verma, Nishant Singh, Sushil Kumar, Deepak Kumar Painkra, Swaroop B. Banerjee, K. P. Subramaniam, Bhas Bapat, M. B. Dadhania, P. Janardhan, Anil Bhardwaj. 2025-07-24. One Year of ASPEX-STEPS Operation: Characteristic Features, Observations and Science Potential. https://arxiv.org/abs/2507.18117

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