Magnetic Properties of C IV Doppler Shift Patterns
Abstract
The relationship between Doppler shift patterns observed in the transition region and magnetic field patterns observed in the photosphere is studied using coaligned pairs C IV Dopplergrams and Fe I magnetograms. Categories of magnetic features are defined--including neutral lines, unipolar regions, strong field regions, weak field regions, and magnetic boundaries--and from these, magnetic associations are determined for 159 V0 lines separating areas of relative blueshift and redshift observed in and nearby to active regions. The cases are subdivided on the basis of whether blueshifts or redshifts are observed on the side of the V0 line nearest the limb. Two of the main results are that V0 lines associated with neutral lines tend to have limbward blueshifts, while V0 lines associated with unipolar regions tend to have limbward redshifts. These and other results provide supportive evidence for the active region model proposed recently by Klimchuk, in which relative redshifts occur where strong vertical fields penetrate the surface, and relative blueshifts occur where these same fields have spread out to become horizontal. It is likely that the relative blueshifts correspond to absolute Doppler shifts of very small amplitude, possibly even redshifts. (rh)
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1988
- Accession Number
- ADA198602
Entities
People
- James A. Klimchuk
Organizations
- Stanford University