Abstract Details
| Name: Nishtha Sachdeva Affiliation: Indian institute of Science education and Researc, Conference ID: ASI2015_588 Title : CONSTRAINING NEAR-EARTH MHD TURBULENCE LEVELS USING FORBUSH DECREASE PRECURSORS Authors and Co-Authors : PRASAD SUBRAMANIAN(IISER Pune), SUNIL GUPTA, H. M. ANTIA AND THE GRAPES-3 TEAM (TIFR, MUMBAI) Abstract Type : Oral Abstract Category : Sun and the Solar System Abstract : Earth-Directed Coronal Mass Ejections and their associated shocks can cause sudden dip in the intensity of galactic cosmic rays observed at the Earth; these are called Forbush Decreases. Forbush decrease precursors are anomalies in the cosmic ray intensities that are detected before the Forbush decrease event. Charged particles with low pitch angles escape the mirroring effect of the emhanced magnetic fields (which create the Forbush Decrease). Such precursor decreases can give advance warnings of the turbulence levels near Earth and arrival time and strength of the shock hitting the Earth. Turbulence in the near-Earth space environment ought to destroy the identity of such precursors via pitch angle scattering. We therefore seek to constrain the upstream turbulence levels by studying typical precursor lifetimes and link it to observations with the GRAPES-3 Muon Telescope. |