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Found 4 entries in the Bibliography.
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Solar activity variations of equatorial spread F occurrence and sustenance during different seasons over Indian longitudes: Empirical model and causative mechanisms
A comprehensive analysis using nearly two decades of ionosonde data is carried out on the seasonal and solar cycle variations of Equatorial Spread F (ESF) irregularities over magnetic equatorial location Trivandrum (8.5\textdegreeN, 77\textdegreeE). The corresponding Rayleigh Taylor (RT) instability growth rates (γ) are also estimated. A seasonal pattern of ESF occurrence and the corresponding γ is established for low solar (LSA), medium solar (MSA) and high solar (HSA) activity p ...
Haridas, M.K.; Manju, G.; Arunamani, T.;
Published by: Advances in Space Research Published on: 05/2018
YEAR: 2018   DOI: 10.1016/j.asr.2018.02.040
On the equinoctial asymmetry in the threshold height for the occurrence of equatorial spread F
In the present study, the threshold height (h Fc) for ESF occurrence irrespective of the polarity of the meridional winds during vernal and autumnal equinoxes is investigated using a large database spread over 1993\textendash2008. The characteristics of the thermosphere during the two equinoxes have also been examined using TIMED/GUVI O/N2 data. The major aspects that have emerged are (i) presence of significant equinoctial asymmetry inh Fc\ for the years examined, (ii) increas ...
Published by: Journal of Atmospheric and Solar-Terrestrial Physics Published on: 03/2015
YEAR: 2015   DOI: 10.1016/j.jastp.2015.01.008
First observational evidence of the modulation of the threshold height h'Fc for the occurrence of equatorial spread F by neutral composition changes
\ In the present study, the seasonal and solar activity variations of the threshold height for equatorial spread F occurrence irrespective of the polarity of the meridional winds during magnetically disturbed period are presented for the first time. The modulation of the seasonal pattern of the threshold height by the seasonal mean O/N2 values is also examined. The Ionosonde data of magnetic equatorial location Trivandrum (8.5\textdegreeN, 76.5\textdegreeE) and low latitude station SHAR (13.7\t ...
Haridas, M.; Manju, G.; Pant, Tarun;
Published by: Journal of Geophysical Research: Space Physics Published on: 06/2013
YEAR: 2013   DOI: 10.1002/jgra.50331
Ionospheric response to a geomagnetic storm during November 8--10, 2004
This paper investigates the response of the equatorial, and near equatorial, ionosphere to geomagnetic disturbances during the period November 8-10, 2004. Ionosonde data from Trivandrum (8.5\textdegreeN 77\textdegreeE and dip 0.5\textdegreeN) and SHAR (13.5\textdegreeN, 80.2\textdegreeE, dip \~5.5\textdegreeN), magnetic field data from Tirunelveli (8.7\textdegreeN, 76.9\textdegreeE, dip latitude 0.5\textdegreeS) and Alibag (18.64\textdegreeN, 72.87\textdegreeE), and GUVI O/N2 data in the Indian longitude sector ...
Simi, K.; Manju, G.; Haridas, M.; Nayar, S.; Pant, Tarun; Alex, S.;
Published by: Earth, Planets and Space Published on: 05/2013
YEAR: 2013   DOI: 10.5047/eps.2012.09.005
Equatorial Electrojet; Equatorial ionization anomaly; geomagnetic storm; O/N2 ratio