Faculty

Brief Introduction

I am engaged in teaching and research at the School of Environmental Studies. My area of research spread over solar physics, space-weather and cosmic rays. Currently I focus on space-weather predictions and effects of solar-transient events on the near-Earth environment. Apart from this I also study the kinematics of coronal mass ejections and geo-magnetic storms. 

Contact Info

Phone : 8355883569
Email : arunbabu@cusat.ac.in

Education

• Aug 2008 – Aug 2014: Ph.D. in Physics from Department of Physics, Indian Institute of Science Education and Research, Pune, India. 
• Jul 2004 – May 2006: M.Sc in Physics, Maharajas College, Ernakulam, Cochin, India. 
• Jul 2001 – May 2004: B.Sc in Physics, Maharajas College, Ernakulam, Cochin, India. 

Experience 

• Aug 2023 – Present: Assistant Professor at School of Environmental Studies, Cochin University of Science and Technology, Kochi, Kerala, India.
• Nov 2021 – Aug 2023: Assistant Professor at Department of Physics, St. Albert’s College, Ernakulam, Cochin, Kerala, India.
• Apr 2018 – Apr 2020: Post-doctoral fellow at Instituto de Geofisica, UNAM, University City, Mexico City, Mexico.
• Aug 2017 – Mar 2018: National Post-doctoral fellow(DST/SERB) at Aligarh Muslim University, Aligaarh, Uttar Pradesh, India. 
• Aug 2014 – Aug 2017: Post-doctoral fellow, Department of High-Energy Physics, Tata Institute of Fundamental Research (TIFR), Colaba Mumbai, India. 

About My Research

My research centers on the role of cosmic rays in understanding space weather phenomena, utilizing data from ground-based observatories such as HAWC and GRAPES-3. Through a variety of studies, I explore the interactions between cosmic rays, solar activity, and geomagnetic variations, shedding light on how these elements influence our space environment.

A key focus of my work is the observation of interplanetary flux ropes, which are structures in the solar wind that can impact space weather significantly. In one of my notable studies, we successfully detected an interplanetary flux rope at ground level using HAWC. This research not only enhances our understanding of these structures but also emphasizes the potential of cosmic rays as indicators of complex solar phenomena.

Additionally, I have investigated the transient weakening of Earth's magnetic shield as probed by cosmic ray bursts. This study reveals how such bursts can provide critical insights into geomagnetic disturbances, further establishing the importance of cosmic rays in monitoring space weather events. By linking cosmic ray activity to changes in the geomagnetic field, we can better understand the mechanisms that govern these interactions.

My research also delves into Forbush decreases—rapid drops in cosmic ray intensity associated with solar coronal mass ejections (CMEs) and interplanetary shocks. I have examined the relationship between these decreases and enhancements in the interplanetary magnetic field, providing a clearer picture of their underlying processes.

Moreover, I explore the influence of atmospheric conditions on cosmic ray detection. My work on the dependence of muon intensity on atmospheric temperature contributes to our understanding of how environmental factors affect cosmic ray measurements.

Overall, my research emphasizes the potential of cosmic rays as vital tools for monitoring space weather and enhancing our understanding of solar-terrestrial interactions. Through ongoing studies, I aim to further unravel the complexities of these phenomena and their implications for both space and Earth-based systems.

Students

• • Sruthi Mildred
  • Augustine Sumesh

Publications: 

• • “The first 10 years of the HAWC Gamma-Ray Observatory: science results”, A. Albert et. al., 2025, RMAA, 10, 03. DOI: https://doi.org/10.22201/ia.01851101p.2025.61.03.13
  • “New age observing facilities for Indian astronomy: 2020–2035”, Sethuram, R., Roy, J., Reddy, E. et al., 2025, J Astrophys Astron , 46, 25.https://doi.org/10.1007/s12036-025-10047-x
  • “Characterization and carbon mineralization potential of poultry litter biochar in paddy wetland systems of Kunnukara village, Kerala, India”, Anjali Thaitharanikathil Babu, Anand Madhavan, K. P. Arunbabu, 2025, Environmental Earth Sciences, 84, 459. https://doi.org/10.1007/s12665-025-12474-z
  • Interaction of Cosmic Rays with Magnetic Flux Ropes, Lara et.al., 2024,  Journal of Geophysical Research: Space Physics., 12932478L, DOI:10.1029/2024JA032478
  • Exploring the Coronal Magnetic Field with Galactic Cosmic Rays: The Sun Shadow Observed by HAWC, R. Alfaro et. al., 2024, The Astrophysical Journal, 966, 67. (HAWC Collaboration) DOI
    10.3847/1538-4357/ad3208
  • Galactic Gamma-Ray Diffuse Emission at TeV Energies with HAWC Data, Alfaro R et. al., 2024, The Astrophysical Journal, 961, 104, (HAWC Collaboration) DOI:10.48550/arXiv.2310.09117
  • High-altitude characterization of the Hunga pressure wave with cosmic rays by the HAWC observatory, Ruben Alfaro et al., 2024 Advances in Space Research, 73, 1083. DOI:10.1016/j.asr.2023.09.049
  • The High-Altitude Water Cherenkov (HAWC) observatory in Mexico: The primary detector”, A. U. Abeysekara et al., (HAWC collaboration), 2023, Nuclear Inst. and Methods in Physics Research, A, A 1052, 168253. DOI:https://10.1016/j.nima.2023.168253
  • Constraints on the Very High Energy Gamma-Ray Emission from Short GRBs with HAWC”, A. Albert et. al., (HAWC collaboration), 2022, The Astrophysical Journal, 936, 126, DOI:10.3847/1538-4357/ac880e
  • Long-term Spectra of the Blazars Mrk 421 and Mrk 501 at TeV Energies Seen by HAWC”, A. Albert et.al., (HAWC collaboration), 2022, The Astrophysical Journal, 929, 125A, (HAWC collaboration) DOI:10.3847/1538-4357/ac58f6
  • Cosmic ray spectrum of protons plus helium nuclei between 6 and 158 TeV from HAWC data”, A. Albert et. al., (HAWC collaboration), 2022, Phys. Rev. D, 105, 063021, DOI:10.1103/PhysRevD.105.063021
  • Characterization of the background for a neutrino search with the HAWC observatory”, A. Albert et. al., (HAWC collaboration), 2022, Astroparticle Physics, 137, 102670, DOI:10.1016/j.astropartphys.2021.102670
  • HAWC as a Ground-Based Space-Weather Observatory”, C. Alvarez et al., (Corresponding author for HAWC collaboration), 2021, Solar.Phys, 296, 89. DOI: 10.1007/s11207-021-01827-z
  • TeV emission of Galactic plane sources with HAWC and H.E.S.S ”, H. Abdalla et al., (HAWC collaboration), 2021, The Astrophysical Journal, 917, 6, DOI: 10.3847/1538-4357/abf64b
  • Probing the Sea of Cosmic Rays by Measuring Gamma-Ray Emission from Passive Giant Molecular Clouds with HAWC”, A. Albert et. al., (HAWC collaboration), 2021, The Astrophysical Journal, 914, 106, DOI: 10.3847/1538-4357/abfc47
  • HAWC Search for High-Mass Microquasars”, A. Albert et. al., (HAWC collaboration), 2021, The Astrophysical Journal Letters, 912, L4, DOI: 10.3847/2041-8213/abf35a
  • Spectrum and Morphology of the Very High Energy γ-Ray Source HAWC J2019+368”, A. Albert et. al., (HAWC collaboration), 2021, The Astrophysical Journal, 911, 143, DOI: 10.3847/1538-4357/abecda
  • Evidence that ultra-high-energy gamma-rays are found in the vicinity of powerful pulsars”, A. Albert et. al., (HAWC collaboration), 2021, The Astrophysical Journal Letters, 911, L27, DOI: 10.3847/2041-8213/abf4dc
  • HAWC observations of the acceleration of very-high-energy cosmic rays in the Cygnus Cocoon”, A. U. Abeysekara et al., (HAWC collaboration), 2021, Nature Astronomy. DOI: 10.1038/s41550-021-01318-y
  • A survey of active galaxies at TeV photon energies with the HAWC gamma-ray observatory”, A. Albertet. al., (HAWC collaboration), 2021, The Astrophysical Journal, 907, 67. DOI: 10.3847/1538-4357/abca9a
  • Evidence of 200 TeV photons from HAWC J1825-134”, A. Albert et. al., (HAWC collaboration), 2021, The Astrophysical Journal Letters, 907, 30. DOI: 10.3847/2041-8213/abd77b
  • Multimessenger Gamma-Ray and Neutrino Coincidence Alerts using HAWC and IceCube sub-threshold Data”, H. A. Ayala Solares et.al., (HAWC collaboration), 2021, The Astrophysical Journal, 906, 63. DOI: 10.3847/1538-4357/abcaa4
  • Interplanetary Flux-rope observed at ground level by HAWC”, S.Akiyama et al., (Corresponding author for HAWC collaboration), 2020, The Astrophysical Journal, 905, 73. DOI:10.3847/1538-4357/abc344
  • 3HWC: The Third HAWC Catalog of Very-High-Energy Gamma-ray Sources”, A. Albert et al., (HAWC collaboration), 2020, The Astrophysical Journal,905, 76. DOI:10.3847/1538-4357/abc2d8
  • HAWC and Fermi -LAT Detection of Extended Emission from the Unidentified Source 2HWC J2006+341”, A. Albert et al., (HAWC collaboration), 2020, The Astrophysical Journal Letters,903, L14, DOI:10.3847/2041-8213/abbfae
  • HAWC J2227+610 and its association with G106.3+2.7, a new potential Galactic PeVatron”, A. Albert et. al., (HAWC collaboration), 2020, The Astrophysical Journal Letters. 896L, 29A. DOI:10.3847/2041-8213/ab96cc
  • Search for gamma-ray spectral lines from dark matter annihilation in dwarf galaxies with the High-Altitude Water Cherenkov observatory”, A. Albert et. al., (HAWC collaboration), 2020, Phys. Rev. D, 101, 103001. DOI: 10.1103/PhysRevD.101.103001
  • Constraining the Local Burst Rate Density of Primordial Black Holes with HAWC”, A. Albert et. al., (HAWC collaboration), 2020, JCAP, 2020, 026. DOI:10.1088/1475-7516/2020/04/026
  • Constrains on the Emission of Gamma Rays from M31 with HAWC”, A. Albert et al., (HAWC collaboration), 2020, The Astrophysical Journal, 893, 16A. DOI:10.3847/1538-4357/ab7999
  • Constraints on Lorentz invariance violation from HAWC observations of gamma rays above 100 TeV”, A. Albert et. al., (HAWC collaboration), 2020, Phys.Rev.Lett.,124, 131101. DOI:10.1103/PhysRevLett.124.131101
  • Multiple Galactic Sources with Emission Above 56 TeV Detected by HAWC”, A. U Abeysekara et al., (HAWC collaboration), 2020, Phys.Rev.Lett., 124, 021102. DOI:10.1103/PhysRevLett.124.021102
  • Measurement of the Crab Nebula Spectrum Past 100 TeV with HAWC”, A. U. Abeysekara et al., (HAWC collaboration), 2019, The Astrophysical Journal, 881, 134A. (HAWC collaboration) DOI:10.3847/1538-4357/ab2f7d
  • Measurement of the radial diffusion coefficient of galactic cosmic rays near the Earth by the GRAPES-3 experiment”, Kojima, H., Arunbabu, K. P., Dugad, S. R., et.al., 2018, Phys. Rev D, 98, 022004. DOI:10.1103/PhysRevD.98.022004
  • Was the cosmic ray burst detected by the GRAPES-3 on 22 June 2015 caused by transient weakening of geomagnetic field or by an interplanetary anisotropy?” P.K. Mohanty, K.P. Arunbabu, T. Aziz, et.al., 2018, Phys. Rev D, 97, 082001. DOI:10.1103/PhysRevD.97.082001
  • Dependence of the muon intensity on the atmospheric temperature measured by the GRAPES-3 experiment”, K.P. Arunbabu et al., 2017, Astroparticle Physics, 94, 22. DOI:10.1016/j.astropartphys.2017.07.002
  • Transient Weakening of Earth’s Magnetic Shield Probed by a Cosmic Ray Bursts” P.K. Mohanty, K.P. Arunbabu, et. al., T. Aziz, et.al., 2016, Phys. Rev. Lett. 117, 171101. DOI:10.1103/PhysRevLett.117.171101
  • Role of solar wind speed and interplanetary magnetic field during two-step Forbush decreases caused by Interplanetary Coronal Mass Ejections ”, Baskar, Ankush., Vichare, Geeta.,Arunbabu, K., P., Raghav, Anil., 2016, Ap&SS, 361, 242B. DOI:10.1007/s10509-016-2827-8
  • Fast Fourier Transform to measure pressure coefficient of muons in the GRAPES-3 experiment.”, P.K.Mohanty, S.Ahmad, H.M. Antia, K.P. Arunbabu,et.al., 2016, Astroparticle Physics, 79, 23–30. DOI:10.1016/j.astropartphys.2016.02.006
  • How are Forbush decreases related to interplanetary magnetic field enhancements?”, K.P. Arunbabu et al., 2015, Astronomy & Astrophysics, 580A..41A. DOI:10.1051/0004-6361/201425115
  • Self-similar expansion of solar coronal mass ejections: implications for Lorentz self-force driving”, P. Subramanian, K.P. Arunbabu, A. Vourlidas, A. Mauriya, 2014, The Astrophysical Journal, 790, 125. DOI:10.1088/0004-637X/790/2/125
  • High-rigidity Forbush decreases: due to CMEs or Shock?”, K.P. Arunbabu et al., 2013, Astronomy & Astrophysics, 555, 139. DOI:10.1051/0004-6361/201220830

International Conference proceedings: 

• • Galactic Cosmic Ray increase associated with an interplanetary magnetic cloud observed by HAWC”, Alejandro Lara, K.P. Arunbabu, Tatiana Niembro, Proceedings of 37th International Cosmic Ray Conference (ICRC2021), POS(ICRC2021)1296
  • Atmospheric pressure dependance of HAWC scaler system”, K.P. Arunbabu, Lara, A., Ryan, J. , Proceedings of 36th International Cosmic Ray Conference (ICRC2019) : POS(ICRC2019)1095
  • Effects of the atmospheric electric field on the HAWC scaler rate.”, Ricardo Jara, Lara A., K.P. Arunbabu, James Ryan, Proceedings of 36th International Cosmic Ray Conference (ICRC2019) : POS(ICRC2019)1087
  • Galactic Cosmic Ray Sun Shadow during the declining phase of cycle 24 observed by HAWC”, Alejandro Lara, Paulina Colin, K.P. Arunbabu, James Ryan, Proceedings of 36th International Cosmic Ray Conference (ICRC2019) : POS(ICRC2019)1104
  • Diffusion of cosmic rays in heliosphere, observations from GRAPES-3”, K.P. Arunbabu et. al., Proceedings of 35th International Cosmic Ray Conference (ICRC2017) : POS(ICRC2017)011
  • Atmospheric temperature dependence of muon intensity measured by the GRAPES-3 experiment”, K.P. Arunbabu et. al., Proceedings of 35th International Cosmic Ray Conference (ICRC2017) : POS(ICRC2017)304
  • Transient weakening of geomagnetic shield probed by GRAPES-3 experiment”, P. K. Mohanty, K.P. Arunbabu, S.R. Dugad et. al., Proceedings of 35th International Cosmic Ray Conference (ICRC2017): POS(ICRC2017)092
  • Dependence of the GRAPES-3 EAS trigger rate and particle density on atmospheric pressure and temperature ”, M. Zuberi, S. Ahmad, K.P. Arunbabu et. al., Proceedings of 35th International Cosmic Ray Conference (ICRC2017) : POS(ICRC2017)302
  • Precision measurement of arrival times in an EAS by GRAPES-3 experiment” , V.B. Jhansi, S. Ahmad, K.P. Arunbabu et. al., Proceedings of 35th International Cosmic Ray Conference (ICRC2017): POS(ICRC2017)354
  • Measuring the hourly gain of the scintillator detectors from EAS data” , V.B. Jhansi, S. Ahmad, K.P. Arunbabu et. al., Proceedings of 35th International Cosmic Ray Conference (ICRC2017): POS(ICRC2017)356
  • Long-term correction of GRAPES-3 muon telescope efficiency” , P. K. Mohanty, S. Ahmad, K.P. Arunbabu et. al., Proceedings of 35th International Cosmic Ray Conference (ICRC2017) : POS(ICRC2017)357
  • Extending the range of particle densities observed by GRAPES-3” , A. Chandra, S. Ahmad, K.P. Arunbabu et. al., Proceedings of 35th International Cosmic Ray Conference (ICRC2017) : POS(ICRC2017)479
  • Forbush decrease precursors observed in GRAPES-3”, K.P. Arunbabu et. al., Proceedings of 34th International Cosmic Ray Conference (ICRC2015) : POS(ICRC2015)044
  • Relation of Forbush decrease with interplanetary magnetic fields.”, K.P. Arunbabu et. al., Proceedings of 34th International Cosmic Ray Conference (ICRC2015) : POS(ICRC2015)043
  • Measurements of solar diurnal anisotropy with GRAPES-3 experiment”, P.K. Mohanty, H.M. Antia, K.P. Arunbabu et. al., Proceedings of 34th International Cosmic Ray Conference (ICRC2015) : POS(ICRC2015)042
  • A new method for determining atmospheric pressure coefficient by using fast Fourier transform for muons in the GRAPES-3 experiment”, P.K. Mohanty, H.M. Antia, K.P. Arunbabu et. al., Proceedings of 34th International Cosmic Ray Conference (ICRC2015) : POS(ICRC2015)045
  • How are Forbush decreases related with IP magnetic field enhancements ?”, K.P. Arunbabu et. al., Proceedings of the International Symposium on Solar Terrestrial Physics, ASI Conference Series, 2013, 10, 97. : ASI, ISSTP
  • Dependence of solar diurnal variation on solar wind speed", T Koi et. al., Proceedings of 38th International Cosmic Ray Conference (ICRC2023) : POS(ICRC2023)1340
  • Solar wind velocity dependence of the flow of galactic cosmic rays perpendicular to the ecliptic plane on the polarity of the interplanetary space magnetic field", H Kojima et. al., Proceedings of 38th International Cosmic Ray Conference (ICRC2023) : POS(ICRC2023)1339
  • “Response of Galactic Cosmic Rays to Solar Disturbances: A Study of the May 2024 Forbush De-
    crease with GRAPES-3 Muon Telescope”, Kojima et. al., 39th International Cosmic Ray Conference
    (ICRC2025) POS(ICRC2025)1310 https://pos.sissa.it/501/1310/pdf
  • “The May 2024 Interplanetary Coronal Mass Ejections Observed by HAWC”, A. Lara et. al., 2024 AGU
    Fall Meeting Abstracts, SH21C-2833. SH21C-2833
  • “Study of modulation cycles of cosmic ray diurnal anisotropy variation using 22 years of GRAPES-3
    muon data”, M. Zuberi et. al. Proceedings of 38th International Cosmic Ray Conference (ICRC2023)
    POS(ICRC2023)1349