A5090663557- Earthquake Detection and Analysis
- Ionosphere and magnetosphere dynamics
- Solar and Space Plasma Dynamics
- earthquake and tectonic studies
- Seismic Waves and Analysis
- Geophysics and Gravity Measurements
- Seismology and Earthquake Studies
- Geomagnetism and Paleomagnetism Studies
- Atmospheric Ozone and Climate
- Lightning and Electromagnetic Phenomena
- Radio Wave Propagation Studies
- GNSS positioning and interference
- Geological and Geochemical Analysis
- Geochemistry and Geologic Mapping
- Optical Wireless Communication Technologies
- Geophysical and Geoelectrical Methods
- Optical Polarization and Ellipsometry
- Geophysics and Sensor Technology
- Power Line Communications and Noise
- Wireless Communication Networks Research
- Landslides and related hazards
- Statistical and numerical algorithms
- Surface Roughness and Optical Measurements
- Advanced Optical Sensing Technologies
- Maritime Ports and Logistics
Northumbria University
2022-2025
Physical Research Laboratory
2020-2022
S.N. Bose National Centre for Basic Sciences
2018-2020
Indian Centre for Space Physics
2014-2018
Reliance Industries (India)
2006
Geological Survey of India
1991-2005
We focus on the possible thermal channel of well-known Lithosphere-Atmosphere-Ionosphere Coupling (LAIC) mechanism to identify behavior anomalies during and prior strong seismic events. For this, we investigate variation Surface Latent Heat Flux (SLHF) as resulting from satellite observables. demonstrate a spatio-temporal in SLHF before after set events occurred Kathmandu, Nepal, Kumamoto, Japan, having magnitudes 7.8, 7.3, 7.0, respectively. Before studied earthquake cases, significant...
Abstract Van Allen radiation belt electron dynamics are governed by a multitude of physical processes that can simultaneously drive acceleration, transport and loss. However, each individual process be linked to specific energy‐dependent pitch angle distribution (PAD). We employ new, unsupervised machine learning technique on 7‐year Probe Relativistic Electron‐Proton Telescope data discover six PADs successfully describe 93% outer relativistic electrons, two of: pancake, butterfly, flattop....
Abstract The Earth's inner magnetosphere contains multiple electron populations influenced by different factors. cold electrons of the plasmasphere, warm plasma that contributes to ring current, and relativistic radiation belts often seem behave independently. Using omni‐directional flux energy measurements from HOPE Magnetic Electron Ion Spectrometer instruments aboard Van Allen Probes, we provide a detailed density temperature description magnetosphere, offering comprehensive statistical...
Abstract Energetic particle precipitation into the atmosphere has been identified as a key loss process for electrons in Earth's outer radiation belt region. However, direct measurements of electron flux precipitating are challenging from high altitude low inclination spacecraft, such Van Allen Probes, due to small angular size cone along orbital path these high‐altitude spacecraft. Here we use data Polar Orbiting Environmental Satellites (POES)/Space Environment Monitor low‐Earth orbit...
We present perturbations in very low frequency (VLF) signals received at Ionospheric & Earthquake Research Centre (IERC) (Lat. 22.50°N, Long. 87.48°E) during and prior to two earthquakes, one on 11 March 2011 11:16:24 LT (M = 9) Honshu, Japan another 12 May 2015 12:35:19 7.3) Kodari, Nepal. The VLF signal transmitted from JJI (22.2 kHz) 32.05°N, 131.51°E) showed strong shift VLF-sunrise terminator times towards night-time few days both the earthquakes. These earthquakes took place near...
Study of seismo-ionospheric coupling mechanism demands the quiet geomagnetic condition to eliminate any kind contamination in lower atmospheric and ionospheric parameters. In this manuscript, we present effect back two storms before a strong earthquake happened Imphal, India on January 4, 2016 (M = 6.7). We studied irregularities for duration 31 days by computing nighttime fluctuations Very Low Frequency (VLF) radio signal received transmitter JJI (22.2 kHz) Japan at Ionospheric Earthquake...
Chorus waves play a key role in outer Van Allen electron belt dynamics through cyclotron resonance. Here, we use Probes data to reveal new and distinct population of intense chorus excited the heart radiation during main phase geomagnetic storms. The power is typically ~ 2-3 orders magnitude greater than pre-storm levels, are generated when fluxes 10-100 keV electrons approach or exceed Kennel-Petschek limit. These rapidly scatter into loss cone, capping flux value close limit predicted by...
Abstract Characteristics of very low frequency (VLF) signal depends on solar illumination across the propagation path. For a long path, zenith angle varies widely over path and this has significant influence characteristics. To study effect, Indian Centre for Space Physics participated in 27th 35th Scientific Expedition to Antarctica. VLF signals transmitted from transmitters, namely, VTX (18.2 kHz), Vijayanarayanam, India, NWC (19.8 North West Cape, Australia, were recorded simultaneously...
Abstract The behaviour of relativistic electrons in the radiation belt is difficult to diagnose as their dynamics are controlled by simultaneous physical processes, some which may be still unknown. Signatures these processes identify large amounts data; therefore, a machine learning approach developed classify energetic electron distributions have been driven different mechanisms. A series unsupervised tools applied 7 yrs Van Allen Probe Relativistic Electron-Proton Telescope data six...
Van Allen radiation belt electron dynamics are governed by a wide range of physical processes that can simultaneously drive acceleration, transport and loss. However, each individual process be linked to specific energy-dependent pitch angle distribution (PAD). We employ new, unsupervised machine learning technique on 7-years Probe Relativistic Electron-Proton Telescope data discover six PADs, two of: pancake, butterfly, flattop, successfully describe >70% classified relativistic PADs....
We present a statistical investigation (September 2012 - September 2017) of pitch angle distribution (PAD) energetic electrons (∼30 keV 1 MeV) in the outer radiation belt (L ≥ 3) during CME- and CIR-driven geomagnetic storms using Van Allen Probe measurements. selected based on minimum SYM-H being less than -50 nT classified according to their drivers. Thus, we obtained 23 24 storms. During storm intervals, resolved electron flux measurements are from MagEIS instrument on-board Probe-A...
Abstract We present, for the first time, a plasmaspheric hiss event observed by Van Allen probes in response to two successive interplanetary (IP) shocks occurring within an interval of ∼2 h on December 19, 2015. The shock arrived at 16:16 UT and caused disappearance ∼30 min. Combined effect plasmapause crossing, significant Landau damping suprathermal electrons their gradual removal magnetospheric compression led hiss. Calculation electron phase space density linear wave growth rates showed...