Udaipur Solar Observatory

 
 

Deputy Head (Admin) : Prof. Nandita Srivastava                        Deputy Head (Tech) : Prof. Shibu K Mathew
Overview
Research activities of the observatory encompass study of solar activity and solar origin of space weather.  

SUIT MEET - (16-17, DEC, 2015)

Research Programmes
Measurement of solar magnetic fields for studies of evolution of these magnetic fields in relation to solar eruptive phenomena like solar flares and coronal mass ejections; studies of the effects of solar activity on parameters of the solar oscillations; studies of the effects of solar flares on the surface and sub-surface flows in the Sun; studies of solar phenomena at high angular resolution by the application of modern techniques like speckle interferometry and adaptive optics.

Facilities
Telescopes for solar observations (Solar Vector Magnetograph, H-alpha high resolution Spar telescope, H-alpha full disk Razdow telescope, Global Oscillation Network Group telescope), laboratories for developing state-of-the-art back-end instrumentation, archived data on solar activity and connectivity to main campus of PRL for using library and external archival facilities. A 50 cm aperture Multi-Application Solar Telescope (MAST) is being installed at the island site of USO.

Ph.D. Courses Offered

  • Solar Physics (as part of Astronomy course)

Select List of Recent Publications

Vemareddy, P., Ambastha, A., Maurya,R.A., and Chae, J., "On the Injection of Helicity by Shearing Motion of Fluxes in Relation to Flares and CMEs" Astrophys. J. 2012, 761, 86

Vemareddy, P., Ambastha, A., Maurya,R.A., " On the Role of Rotating Sunspots in the Activity of Solar Active Region NOAA 11158", Astrophys. J., 2012, 761, 60

Joshi, A.D., Srivastava, N., Mathew, S.K., Martin, S.F., "Rapid Formation and Disappearance of a Filament Barb", Solar Physics, DOI:10.1007/s11207-013-0295-7 (2013) (published online)

Sharma, R., Srivastava, N., Chakrabarty, D, MoestlC., and Hu, Q. "Interplanetary and Geomagnetic consequences of January 5, 2005 CMEs associated with solar eruptive filaments", Journal of Geophysical Research, (2013), (In press)

Mishra, W. and Srivastava, N., "Estimating the arrival time of Earth-directed CMEs at in situ spacecraft using COR and HI observations from STEREO", Astrophysical Journal, (2013), (In press)

Sharma, R., and Srivastava, N., "Presence of solar filament plasma detected in interplanetary coronal mass ejections by in-situ spacecraft", Journal of Space Weather and Space Climate, Volume 2, id. A10, 10.1051/swsc/2012010, (2012)

Joshi, A. D. and Srivastava, N., "Acceleration of coronal mass ejections from 3D reconstruction of STEREO Images", The Astrophysical Journal, Volume 739, Issue 1, article id. 8, (2012)

Maurya, R. A. , Vemareddy, P. Ambastha, A., "Velocity and Magnetic Transients Driven by the X2.2 White-Light Flare of 2011 February 15 in NOAA 11158", Astrophysical Journal , 747, 134 (2012)

Vemareddy, P.; Maurya, R. A.; Ambastha, A.,"Filament Eruption in NOAA 11093 Leading to a Two-Ribbon M1 Class Flare and CME", Solar Physics, 277, 337, (2012)

Varma, R.K., Bannerjee, S. B. and Ambastha, A., "Macro-scale observation of curl-free vector potential: A manifestation of quantum modulation of the de Broglie wave", Eur. Phys. J. D, 66, 39, (2012)

A. D. Joshi and Nandita Srivastava, "Kinematics of two eruptive prominences observed by EUVI/STEREO", Astrophysical Journal , 730, 104 (2011)

Anand D. Joshi, and Nandita Srivastava "Acceleration of coronal mass ejections from three-dimensional reconstruction of STEREO images", Astrophysical Journal, 739, 8 (2011)

Nandita Srivastava, Mierla Marilena and L. Rodriguez,"On three-dimensional aspects of CMEs, their source regions and interplanetary manifestations: Introduction to special issue", JASTP , 73, 1077 (2011)

Olga Panasenco, Sara Martin, A. D. Joshi and Nandita Srivastava, "Rolling motion in eruptive prominences observed by STEREO", JASTP , 73, 1129 (2011)

Brajesh Kumar, P. Venkatakrishnan, Savita Mathur, Sanjiv Kumar Tiwari, and R.A. Garcia "On the flare-induced seismicity in the active region NOAA 10930 and related enhancement of global waves in the Sun", Astrophysical Journal, 743, 29 (2011)

Rohan E. Louis, R. Luis Bellot Rubio, Shibu K. Mathew, and P. Venkatakrishnan "Supersonic downflows at the umbra-penumbra boundary of sunspots", Astrophysical Journal, 727, 49 (2011)

S. Gosain, S. K. Mathew and P. Venkatakrishnan, "Acoustic power absorption and its relation to vector magnetic field of a sunspot", Solar Physics, 268, 335 (2011)

A. R. Bayanna, S. K. Mathew, K. Sankarasubramanian, P. Venkatakrishnan, J. Singh and B. R. Prasad, "Issues with external occultation of a coronagraph" Experimental Astronomy, 29, 145 (2011)

Ramit Bhattacharyya, B.C. Low, and P.K. Smolarkiewicz "On spontaneous formation of current sheets: Untwisted magnetic fields", Physics of Plasmas, 17, 290 (2010)

Sanjiv Kumar Tiwari, P. Venkatakrishnan, and Sanjay Gosain "Magnetic non-potentiality of solar active regions and peak X-ray flux of the associated flares", Astrophysical Journal, 721, 622 (2010)

S. Gosain, S. K. Tiwari and P. Venkatakrishnan, "On the estimate of magnetic non-potentiality of sunspots derived using Hinode SOT/SP observations: Effect of polarimetric noise", The Astrophysical Journal, 720, 1281 (2010)

S. Gosain and P. Venkatakrishnan, "The evolution of twist shear and dip shear during X-class flare of 2006 December 13: Hinode observations", The Astrophysical Journal, 720, L137 (2010)

P. Venkatakrishnan, and Sanjiv Kumar Tiwari "Magnetic tension of sunspot fine structures", Astronomy and Astrophysics Lett., 516, 5 (2010)

Brajesh Kumar, Savita Mathur, R.A. Garcia, and P. Venkatakrishnan "On the flare induced high-frequency global waves in the Sun", Astrophysical Journal Lett., 711, 12 (2010)

A.D. Joshi, Nandita Srivastava, and S.K. Mathew "Automated detection of filaments and their dissappearance using full-disc H-alpha images", Solar Physics, 262, 425 (2010)

R. A. Maurya and A. Ambastha, "A technique for automated determination of flare ribbon separation and energy release", Solar Physics, 262, 337 (2010)

R. A. Maurya and A. Ambastha, "Sub-surface meridional flow, vorticity and the lifetime of solar active regions", The Astrophysical Journal, 714, L196 (2010)

P. Venkatakrishnan and S. K. Tiwari, "Magnetic tension of sunspot fine structures", Astronomy and Astrophysics, 516, L5 (2010)

S. Gosain, P. Venkatakrishnan, and Sanjiv Kumar Tiwari "Hinode observations of coherent lateral motion of penumbral filaments during an X-class flare", Astrophysical Journal Lett., 706, 240 (2009)

P. Venkatakrishnan, and Sanjiv Kumar Tiwari "On the absence of photospheric net currents in vector magnetograms of sunspots obtained from Hinode (SOT/SP)" Astrophysical Journal Lett., 706, 114 (2009)

Nandita Srivastava, B. Inhester, M. Mierla, B. Podlipnik "3D reconstruction of the leading edge of the 20 May 2007 partial Halo CME", Solar Physics, 259, 213 (2009)

Bhuwan Joshi, Astrid Veronig, K.-S, Cho, S.-C, Bong, B.V. Somov, and Y.-J, Moon "Magnetic reconnection during the two-phase evolution of a solar eruptive flare", Astrophysical Journal, 706, 143 (2009)

Sanjiv Kumar Tiwari, P. Venkatakrishnan, and K. Sankarasubramanian "Global twist of sunspot magnetic fields obtained from high resolution vector magnetograms", Astrophysical Journal Lett., 702, 133 (2009)

Nandita Srivastava, Shibu K. Mathew, R. E. Louis, and T. Wiegelmann "Source region of the 18 November 2003 Coronal Mass Ejection that led to the strongest magnetic storm of Cycle 23", J. Geophysical Res., 114, A03107 (2009)

Shibu K. Mathew, V. Zakharov, and S. K. Solanki "Stray light correction and contrast analysis of Hinode broad-band images", Astronomy & Astrophysics Lett., 501, L19 (2009)

Sanjiv Kumar Tiwari, P. Venkatakrishnan, Sanjay Gosain, and Jayant Joshi "Effect of polarimetric noise on the estimation of twist and magnetic energy of force-free fields", Astrophysical Journal , 700, 199 (2009)

Ram Ajor Maurya, Ashok Ambastha, and S.C. Tripathy "Variations in p-mode parameters with changing onset time of a large flare", Astrophysical Journal Lett., 706, 235 (2009)

Ram Ajor Maurya, and Ashok Ambastha, "Transient magnetic and Doppler features related to the white-light flares in NOAA 10486", Solar Physics, 258, 31 (2009)

P. Venkatakrishnan, Brajesh Kumar and Wahab Uddin, "Co-spatial evolution of photospheric Doppler enhancements and H-alpha flare ribbons observed during the solar flare of 2003 October 28", Mon. Not. R. Astron. Soc. Lett., 387, L69 (2008)

Rohan E. Louis, A. Raja Bayanna, Shibu K. Mathew and P. Venkatakrishnan, "Dynamics of sunspot light bridges as revealed by high-resolution images from Hinode", Solar Physics, 252, 43 (2008)

Shibu K. Mathew, "Enhanced p-mode absorption seen near the sunspot umbral-penumbral boundary", Solar Physics, 252, 515 (2008)

R. Sridharan, A. Raja Bayanna, Rohan E. Louis, Brajesh Kumar, Shibu K. Mathew and P. Venkatakrishnan, "An Image Stabilization System for solar observations", Proc. of SPIE, 6689, 66890Z (2007)

A. Ambastha, "Evolution of magnetic and velocity fields in super-active region NOAA and large flare of October 28, 2003", Sun and Geosphere, 2(1), 13 (2007)

Shibu K. Mathew, V. Martinez Pillet, S. K. Solanki and N. A. Krikova, "Properties of sunspots in cycle 23. I. Dependence of brightness on sunspot size and cycle phase", Astronomy & Astrophysics, 465, 291 (2007)

Brajesh Kumar, P. Venkatakrishnan, A. Raja Bayanna and K. Venugopalan, "Site characterization using solar H-alpha images", Solar Physics, 241, 427 (2007)

A. Ambastha, B. Ravindra and Sanjay Gosain, "H-alpha observations of 8 June 2004 Venus transit", Solar Physics, 233, 171 (2006)

A. Ambastha and H. M. Antia, "Possibility of excitation of low-l p-modes by energetic solar transients", Solar Physics, 238, 219 (2006)

Brajesh Kumar and B. Ravindra, "Analysis of enhanced velocity signals observed during solar flares", J. Astrophysics & Astronomy, 27, 425 (2006)

Sanjay Gosain, P. Venkatakrishnan and K. Venugopalan, "Design of instrument control software for solar vector magnetograph at Udaipur Solar Observatory", Experimental Astronomy, 18, 31 (2006)

more about the Division . . .

Udaipur Solar Observatory