Abstract Details
| Name: Sanchita Pal Affiliation: CESSI, IISER Kolkata Conference ID: ASI2018_1239 Title : A SUN-TO-EARTH ANALYSIS OF MAGNETIC HELICITY OF AN INTERPLANETARY CORONAL MASS EJECTION Authors and Co-Authors : Sanchita Pal1, Nat Gopalswamy2, Dibyendu Nandy1, 3, Sachiko Akiyama2, 4, Seiji Yashiro2, 4, Perti Makela2, 4, and Hong Xie2, 4 1 Center of Excellence in Space Sciences India, Indian Institute of Science Education and Research Kolkata, Mohanpur 741246, West Bengal, India, 2 NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA, 3Department of Physical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur 741246, West Bengal, India, 4The Catholic University of America, Washington DC 20064, USA Abstract Type : Poster Abstract Category : Sun and the Solar System Abstract : Study of connecting the helicity of magnetic flux ropes through the Sun-Earth system has important implications for the origin of helicity in the interplanetary medium and the topology of interplanetary coronal mass ejection (ICME) flux ropes at 1 AU. Here we calculate and compare the magnetic helicity in the 17-18 March 2013 ICME flux-rope at 1 AU and in its solar source. The associated coronal mass ejection (CME) erupted on 15 March 2013 with an M1.1 flare from NOAA active region 11692. We measure the magnetic helicity of flux rope using its magnetic and geometric properties near the Sun and at 1 AU. We use forward-modeling of white-light CME observations to obtain the geometrical properties of the near-Sun flux rope and combine it with the reconnection flux derived using post-eruption arcade (PEA) method to extract the magnetic properties of the flux rope. To get the magnetic and geometric information of the 1-AU ICME, we use a constant-α force-free cylindrical flux rope model fit to the in situ observations. We find a good correspondence in both amplitude and sign of the helicity between the ICME and the CME assuming a semi-circular ICME flux rope with a length of π AU. We find that about 83% of the total flux rope helicity at 1 AU is injected by the magnetic reconnection in the low corona. |