Doppler shift velocity calculations of multi-wavelength coronal diagnostic spectrometer data using various background corrections

Modeling of the energy balance in coronal loops requires the observation of temperature, density and velocity at the loop foot-points to find boundary conditions. Calculations are then compared with observations at other points. To achieve this, a Joint Observing Program (JOP161) was carried out 15 April 2003, with coordination between the CDS (Coronal Diagnostic Spectrometer), EIT (Extreme Ultraviolet Imaging Telescope), MDI (Michelson Doppler Imager) and SUMER (Solar Ultraviolet Measurements of Emitted Radiation) instruments on SOHO (Solar and Heliospheric Observatory) and TRACE (Transition Region and Coronal Explorer). CDS measures emission lines from the solar corona and solar transition region in the extreme ultraviolet part of the energy spectrum. The objectives of this part of the research were to measure multi-wavelength Doppler shift velocities for quiet Sun background using CDS and then to determine the calibration needed to calculate accurate Doppler shift velocities of the multi-wavelength data.