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Propagating Disturbances in open and closed magnetic structures of the Sun (Dipankar Banerjee)

When Feb 14, 2012
from 02:00 PM to 03:00 PM
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by Dipankar Banerjee (CPA & Indian Institute of Astrophysics)

Room C200 B02.18

Abstract

Propagating disturbances are observed along open and closed magnetic structures of the sun. For characterizing the nature of the propagating disturbances a combination of spectroscopy and imaging is essential. In this talk I will show examples of such observations using SUMER/SoHO, EIS/Hinode with imaging sequences from AIA/SDO. We find two different groups of periodicities, short (<3 min) and long (>9 min) at different locations and circumstances. In the short range we find oscillations with periodicities as low as 50 s. Shorter periodicities show oscillations in all the three line parameters and the longer ones only show in intensity and Doppler shift but not in the line width. Often Line profiles at these locations do not show any visible blue-shifted component and can be fitted well with a single Gaussian. This allows us to conclude that the propagating disturbances represent waves and not flows. In the last part of my Talk I will also provide an update on the current status of the two large Indian solar observatory projects, namely the space coronagraph project called Aditya and ground based facility from Himalayas called NLST.