Astronomy and Astrophysics – Astrophysics
Scientific paper
Mar 1998
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1998a%26a...331..771m&link_type=abstract
Astronomy and Astrophysics, v.331, p.771-781 (1998)
Astronomy and Astrophysics
Astrophysics
25
Sun: Magnetic Fields, Sun: Infrared, Polarization
Scientific paper
An estimate of the fraction of magnetic flux in intrinsically weak-field form, i.e. fields with less than 1 kG intrinsic strength, in the quiet Sun is presented. We find that on average approximately 2/3 of the flux is in weak-field form, although our data allow a range of values between 25%\ and 85%. These estimates have been derived with the help of radiative transfer model calculations from low-noise scans through the quiet Sun at fixed wavelengths within a Zeeman sensitive spectral line at 1.56 mu m. They represent the first rapidly modulated polarimetric observations of solar 1.56 mu m radiation. These scans show that the polarimetric signature near the core of the line exhibits a very different spatial structure than in the outer line wings. Since the outer part of the line profile is only sensitive to intrinsically strong magnetic fields, while the central part reacts also to intrinsically weak fields, this implies that intrinsically weak fields are distributed differently on the surface than strong fields are (weak-field features lie closer together). The spatial distribution suggests that the strong fields we are observing are network elements, whereas the weak fields are intranetwork features. Further results, such as the average distance between weak and strong field features, flux distribution, spatial power spectra and the Stokes asymmetry of intrinsically weak fields are also presented. In particular, we find that the flux per magnetic feature is distributed lognormally, in agreement with a similar finding for sunspot umbral areas by Bogdan et al. (1988).
Livingston William Charles
Meunier Nicolas
Solanki Sami K.
No associations
LandOfFree
Infrared lines as probes of solar magnetic features. XIII. The relative flux in weak and strong quiet-sun magnetic fields does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Infrared lines as probes of solar magnetic features. XIII. The relative flux in weak and strong quiet-sun magnetic fields, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Infrared lines as probes of solar magnetic features. XIII. The relative flux in weak and strong quiet-sun magnetic fields will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1655756