
TY  - JOUR
A1  - P Jones, Harrison 
T1  - Recent Studies of Magnetic Canopies
JF  - Australian Journal of Physics
JO  - Aust. J.  Phys.
Y1  - 1985
VL  - 38
IS  - 6
SP  - 919
EP  - 928
KW  - 
UR  - https://doi.org/10.1071/PH850919 
N2  - Two current studies are described which stem from Giovanelli's seminal studies of the spreading of chromospheric fields near active regions and active-region network. First, improved observ~tional techniques are described for obtaining magnetograms in the Ca II 8542 A, Fe I 8688 A, and C I 9111 A lines which at least in principle allow for more accurate treatment of instrumental noise and allow better inference of field .orientation. Second, a generalized response function is developed for calculating theoretical magnetograph signals from arbitrary line-of-sight variations of magnetic field, and initial applications to two-dimensional, potential-field models of network fields are described. Preliminary indications are that potential-field models can better explain the presence of low-lying, diffuse horizontal fields than can thin flux-tube models, but fail to predict a differential response between the different lines. 
ER  -

