IIA Institutional Repository

Browsing by Author "Selvendran, R"

Browsing by Author "Selvendran, R"

Sort by: Order: Results:

  • Filament activity in a quiet region flare 
    Sundararaman, K; Gupta, S. S; Selvendran, R (Indian Academy of Sciences, 1993-03)
    We have taken the case of a circular H-alpha filament observed on May 9, 1979 erupting into a double-ribbon flare associated with a nonspot region. The plage motions are responsible for the filament reorientation and, here ...
  • Full-disk synoptic observations of the chromosphere using Hα telescope at the Kodaikanal Observatory 
    Ravindra, B; Prabhu, K; Rangarajan, K. E; Bagare, S. P; Singh, J; Kemkar, P. M. M; Thulasidharen, K. C; Gabriel, F; Selvendran, R (IOP Publishing, 2016-08)
    This paper reports on the installation and observations of a new solar telescope installed on 2014 October 7 at the Kodaikanal Observatory. The telescope is a refractive type equipped with a tunable Lyot Hα filter. A CCD ...
  • H-alpha flare of 14 March, 1984 -- Evidence for reconnection? 
    Sundararaman, K; Aleem, S. M; Singh, J; Selvendran, R; Thiagarajan, R (Springer, 1994-01)
    Kodaikanal H-alpha monochromatic and white-light observations are used to study the circular flare of 14 March, 1984. We report here the dynamic activity of the H-alpha filament, which attained a severe twist before erupting ...
  • On the triggering of quiet region flares without filament activation 
    Sundararaman, K; Selvendran, R (Astronomical Society of India, 1997)
    Using Kodaikanal Observations we have analysed the cases of quiet region flares which are not associated with any filament activation. The rotations of the plages play a major role in triggering these spotless flares. The ...
  • The role of sunspot umbral rotation in triggering solar flares 
    Sundararaman, K; Ramesh, K. B; Selvendran, R (Astronomical Society of India, 2003)
    The evolution of large active regions NOAA 9393 and NOAA 9433 observed during March and April 2001 respectively on their successive rotation and the active region NOAA 10069 that appeared during August 2002 were studied. ...
  • Spot and filament rotation in a sigmoidal flare 
    Sundararaman, K; Ramesh, K. B; Selvendran, R (Astronomical Society of India, 2001)
    The role played by the rotation of the umbrae in a sunspot with respect to the H? filament in inducing magnetic shear for the sigmoidal brightening is reported in this paper. We carried out these studies by using photoheliogram ...
  • Sunspot drawings at Kodaikanal Observatory: a representative results on hemispheric sunspot numbers and area measurements 
    Ravindra, B; Kumaravel, P; Selvendran, R; Samuel, Joyce; Kumar, P; Nancy Jassoria; Navneeth, R. S (Springer, 2020-01)
    The importance of the periodicity in sunspot appearance was well recognized by the mid-19th century. Several observatories around the globe have made the record of sunspots in the form of drawings and preserved them safely ...
  • Sunspot Motions Associated with Flares 
    Sundararaman, K; Selvendran, R; Thiagarajan, R (Kluwer Academic Publishers, 1998-06)
    The evolution of five bipolar sunspot groups during their disk passage leading to flares are analysed and studied using Kodaikanal Observatory photoheliogram and spectroheliogram data. The changes in the orientation angle ...
  • Transit of Venus on 2012 June 06: stray light estimation and restoration of Ca-K images of Twin Telescope from Kodaikanal Observatory 
    Prabhu, K; Rangarajan, K. E; Ravindra, B; Sankarasubramanian, K; Selvendran, R; Kumaravel, P (Astronomical Society of India, 2013-09)
    Observations of the transit of Venus were made from the Kodaikanal Observatory on 2012 June 06 in Ca-K wavelengths. Only half of the event was visible from India. We utilized this unique opportunity to compute the contribution ...

Search DSpace

Browse

My Account