Urmi Doshi
Research Scholar

Ph: +91 80 2238 5956
Fax: +91 80 2238 5957
E-mail: urmi@mpbifr-blr.in

View Full Profile

Research Areas:

• Study of Coronal Mass Ejections related to Sunspot activity
  (under the Guidance of Prof. K. B. Ramesh (IIA))

• M.Sc., The M.S University of Baroda, 2007
• B.Sc., Osmania University Hyderabad, 2004

• Worked as a project student to study open clusters with Dr Priya Hasan, Osmania University, Hyderabad for a period of one year (2007 - 2008)

Research Areas:

Study of Coronal Mass Ejections related to Sunspot activity

Coronal Mass Ejections (CMEs) are the most energetic phenomena in the solar atmosphere and represent the conversion of stored magnetic energy into plasma kinetic energy and flare thermal energy. CMEs have been studied extensively using Large Angle and Spectrometric Coronagraphs (LASCO) on board SOHO since 1996. CME speed varies over two orders of magnitude from ~20 to more than 3000 km/s with an average value of ~475 km/s. The CME angular width ranges from less than 5 degrees to 360 degrees. CMEs with above-average speeds decelerate due to coronal drag, while lower speed ones accelerate.  CMEs with speeds greater than average speed are largely associated with with strong field regions, namely sunspots.  CMEs with speeds greater than the average speed follow the sunspot cycle much better than the entire population of CMEs. Since the disk events of CMEs (Halo CMEs) are associated with sunspots, it is quite interesting to study the latitude distribution of their speeds.  Identification of source regions of CMEs  is an important task of this study.  Source regions for halo CMEs have been identified so far.  Work on the latitude distribution of their speeds is in progress. Also the herculean task of identifying the source regions for limb events have been planned and a tentative sketch of the work has been drawn. While the CMEs data required for this study has been obtained from http://cdaw.gsfc.nasa.gov/, the sunspot data has been collected from ftp://ftp.ngdc.noaa.gov/STP/ SOLAR_DATA / SUNSPOT_REGIONS.  This is expected to provide an insight into the CME phenomena that do not have sunspots as sources.

Publications list:

1. “The Structure and dynamics of young star clusters: King16, NGC 1931, NGC 637 and NGC 189”, in the journal Astrophysics and Space Science,
   Priya Hasan, Hasan S. N. and Urmi Shah, ApSS, 2008, 318, 25.