Search Publications
Nonlinear evolution of oblique whistler waves in radiation belts
Sharma, R. P.; Sharma, Swati; Nandal, P. +1 more
Magnetic power spectrum and formation of coherent structures have been investigated in the present work applicable to Van Allen radiation belt. The nonlinear interaction of high frequency oblique whistler wave and low frequency magnetosonic wave has been investigated. Simulation was performed of the coupled equation of these two waves. The nonline…
Energy budget during an isolated substorm using measurements of multi satellites and geomagnetic indices
Dunlop, M. W.; Ma, Yuduan; Yang, Jian +1 more
Measurements of multi satellites and geomagnetic indices are used to investigate the energy budget during an isolated substorm. The calculation of the energy transfer from the solar wind to the magnetosphere (parameter
Optical imaging and spectral study of FR-I type radio galaxy: CTD 086 (B2 1422+26B)
Pandge, M. B.; Sahu, Sheetal K.; Navale, N. R. +1 more
We present optical imaging and spectroscopic studies of the Fanaroff & Riley class I (FR I) radio galaxy CTD 086 based on Hubble Space Telescope (HST) and Sloan Digital Sky Survey (SDSS) observations. We use isophote shape analysis to show that there is no stellar disk component within CTD 086 and further that the morphological class of the ga…
The bi-directional moving structures in a coronal bright point
Li, Dong; Ning, Zongjun; Su, Yingna
We report the bi-directional moving structures in a coronal bright point (CBP) on 2015 July 14. It is observed by the Atmospheric Imaging Assembly (AIA) onboard Solar Dynamics Observatory (SDO). This CBP has a lifetime of ∼10 minutes, and a curved shape. The observations show that many bright structures are moving intermittently outward from the C…
Kelvin–Helmholtz instability in an active region jet observed with Hinode
Srivastava, A. K.; Zhelyazkov, I.; Chandra, R.
Over past ten years a variety of jet-like phenomena were detected in the solar atmosphere, including plasma ejections over a range of coronal temperatures being observed as extreme ultraviolet (EUV) and X-ray jets. We study the possibility for the development of Kelvin–Helmholtz (KH) instability of transverse magnetohydrodynamic (MHD) waves travel…
Study of magnetic field geometry and extinction in Bok globule CB130
Das, H. S.; Chakraborty, A.
We trace the peripheral magnetic field structure of Bok globule CB130 by estimating the linear polarization of its field stars in the R band. The magnetic field orientation sampled by these stars, aligned on average among themselves, and the polarization produced within the cloud has a different direction from that of Galactic plane with an offset…
Improved SOT (Hinode mission) high resolution solar imaging observations: 2—Photometric properties of sunspot umbral dots
Koutchmy, S.; Adjabshirizadeh, A.; Goodarzi, H.
The origin and evolution of solar sunspots in deep photospheric layers are not yet well understood. The case of a quasi-symmetric single mature sunspot near the solar centre is selected for analysis. We use the best available observations of the partial Sun free of turbulent Earth atmospheric effects from the Solar Optical Telescope (SOT) onboard …
Potential role of kinetic Alfvén waves and whistler waves in solar wind plasmas
Goldstein, M. L.; Sharma, R. P.; Nandal, P. +1 more
Spacecraft observations indicate the signatures of highly oblique kinetic Alfvén waves (KAWs) and whistler waves in the solar wind plasma. In the present work, we explore the possible role of KAWs and whistler waves in the observed solar wind magnetic turbulent spectrum. The nonlinear spatial evolution of KAW is studied including the effects of th…
Possible gamma-ray burst radio detections by the Square Kilometre Array. New perspectives
Capozziello, Salvatore; Ruggeri, Alan Cosimo
The next generation interferometric radio telescope, the Square Kilometre Array (SKA), which will be the most sensitive and largest radio telescope ever constructed, could greatly contribute to the detection, survey and characterization of Gamma Ray Bursts (GRBs). By the SKA, it will be possible to perform the follow up of GRBs even for several mo…
Spectral behavior of Nova GQ Mus in the ultraviolet
Sanad, M. R.; Abdel-Sabour, M. A.
We present ultraviolet spectroscopic study of nova GQ Mus observed with the International Ultraviolet Explorer (IUE) during the period 1983–1985. Different spectra showing the changes in line fluxes at different times are presented. The outflow velocity of the ionized ejecta was calculated to be 1010–2900