IIA Institutional Repository

Browsing by Author "Mathew, S. K"

Browsing by Author "Mathew, S. K"

Sort by: Order: Results:

  • Analysis of a fragmenting sunspot using hinode observations 
    Louis, R. E; Ravindra, B; Mathew, S. K; Bellot Rubio, L. R; Bayanna, A. R; Venkatakrishnan, P (IOP Publishing, 2012-08-10)
    We employ high-resolution filtergrams and polarimetric measurements from Hinode to follow the evolution of a sunspot for eight days starting on 2007 June 28. The imaging data were corrected for intensity gradients, projection ...
  • Bipolar high voltage switching supply for solar video magnetograph 
    Gupta, S. K; Mathew, S. K (Astronomical Society of India, 1998)
  • Constraints on the evolution of the Triton atmosphere from occultations: 1989–2022 
    Sicardy, B; Tej, A; Gomes-Júnior, A. R; Romanov, F. D; Bertrand, T; Ashok, N. M; Lellouch, E; Morgado, B. E; Assafin, M; Desmars, J; Camargo, J. I. B; Kilic, Y; Ortiz, J. L; Vieira-Martins, R; Braga-Ribas, F; Ninan, J. P; Bhatt, B. C; Pramod Kumar, S; Swain, V; Sharma, S; Saha, A; Ojha, D. K; Pawar, G; Deshmukh, S; Deshpande, A; Ganesh, S; Jain, J. K; Mathew, S. K; Kumar, H; Bhalerao, V; Anupama, G. C; Barway, Sudhanshu; Brandeker, A; Floren, H. G; Olofsson, G; Bruno, G; Mao, Y. M; Ye, R. H; Zou, Q. Y; Sun, Y. K; Shen, Y. Y; Zhao, J. Y; Grishin, D. N; Romanova, L. V; Marchis, F; Fukui, K; Kukita, R; Benedetti-Rossi, G; Santos-Sanz, P; Dhyani, N; Gokhale, A; Kate, A (EDP Sciences, 2024-02)
    Context. In about 2000, the south pole of Triton experienced an extreme summer solstice that occurs every ∼650 years, when the subsolar latitude reached about 50°S. Bracketing this epoch, a few occultations probed the ...
  • Dynamical properties of quiescent prominence in He D3 5876 Angstrom line emission 
    Prasad, C. D; Ambastha, A; Mathew, S. K (Astronomical Society of India, 1999)
    We have observed a quiescent prominence with the Coude spectrograph of Udaipur Solar Observatory during May 24-25, 1995. Analysis of two dimenstional spectroscopic data was carried out in order to obtain the line shifts ...
  • Issues with external occultation of a coronagraph 
    Bayanna, A. R; Mathew, S. K; Sankarasubramanian, K; Venkatakrishnan, P; Singh, J; Prasad, B. R (Springer, 2011-04)
    This paper addresses some of the issues related to externally occulted solar coronagraph; vignetting and achievable resolution due to an external occulter. The analytical expression by Evans (J Opt Soc Am 38:1083–1085, ...
  • Magnetic field gradient and flare: study of a small flare in NOAA 8038 
    Mathew, S. K; Ambastha, A (Springer, 2000-11)
    Active region NOAA 8038 was observed from 10 to 13 May, 1997 using the USO solar video magnetograph. During this period, the active region was mostly inactive, and gave rise to only a single notable flare of 1N/C1.3 class ...
  • Membrane-based deformable mirror: intrinsic aberrations and alignment issues 
    Bayanna, A. R; Louis, R. E; Chatterjee, S; Mathew, S. K; Venkatakrishnan, P (Optical Society of America, 2015-03-01)
    A deformable mirror (DM) is an important component of an adaptive optics system. It is known that an on-axis spherical/parabolic optical component, placed at an angle to the incident beam introduces defocus as well as ...
  • The Multi Application Solar Telescope 
    Venkatakrishnan, P; Mathew, S. K; Srivastava, N; Bayanna, A. R; Kumar, B; Ramya, B; Jain, N; Saradava, M (Current Science Association, 2017-08)
    Multi Application Solar Telescope (MAST), a telescope for the detailed study of solar activity, was operationalized at the Udaipur Solar Observatory (USO) of Physical Research Laboratory (PRL), on 16 June 2015. This ...
  • On the line profile changes observed during the X2.2 class flare in the active region NOAA 11158 
    Bayanna, A. R; Kumar, B; Venkatakrishnan, P; Mathew, S. K; Ravindra, B; Mathur, S; Garcia, R. A (IOP Publishing, 2014-02)
    The solar active region NOAA 11158 produced a series of flares during its passage through the solar disk. The first major flare (of class X2.2) of the current solar cycle occurred in this active region on 2011 February 15 ...
  • Properties of umbral dots from stray light corrected hinode filtergrams 
    Louis, R. E; Mathew, S. K; Bellot Rubio, L. R; Kiyoshi, I; Ravindra, B; Raja Bayanna, A (IOP Publishing, 2012-06-20)
    High-resolution blue continuum filtergrams from Hinode are employed to study the umbral fine structure of a regular unipolar sunspot. The removal of scattered light from the images increases the rms contrast by a factor ...
  • Trigger of Successive Filament Eruptions Observed by SDO and STEREO 
    Dhara, Sajal Kumar; Ravindra, B; Kumar, Pankaj; Banyal, R. K; Mathew, S. K; Joshi, B (Springer, 2017-02)
    Using multiwavelength observations from the Solar Dynamics Observatory (SDO) and the Solar Terrestrial Relations Observatory (STEREO), we investigate the mechanism of two successive eruptions (F1 and F2) of a filament in ...
  • Visible emission line coronagraph on Aditya-L1 
    Prasad, B. R; Banerjee, D; Singh, J; Nagabhushana, S; Amit Kumar; Kamath, P. U; Kathiravan, S; Venkata Suresh, Narra; Rajkumar, N; Natarajan, V; Juneja, Madhur; Somu, Pawan; Pant, V; Shaji, Nigar; Sankarsubramanian, K; Patra, Asit; Venkateswaran, R; Adoni, A. A; Narendra, S; Haridas, T. R; Mathew, S. K; Mohan Krishna, R; Amareswar, K; Jaiswa, Bhavesh (Indian Academy of Science, 2017-08-25)
    Solar coronagraph mimics total solar eclipse by blocking the solar disk and enabling the observation of extended coronal atmosphere of the Sun. Visible Emission Line Coronagraph (VELC), on-board Aditya-L1 space mission, ...

Search DSpace

Browse

My Account