Issue |
A&A
Volume 392, Number 3, September IV 2002
|
|
---|---|---|
Page(s) | 1095 - 1104 | |
Section | Planets and planetary systems | |
DOI | https://doi.org/10.1051/0004-6361:20021182 | |
Published online | 09 September 2002 |
Temporal and spatial variations of the magnetic field vector in sunspots
1
ESA Research and Scientific Support Department (RSSD), ESTEC, Keplerlaan 1, 2201 AZ, Noordwijk, The Netherlands
2
National Solar Observatory/Sacramento Peak PO Box 62 Sunspot, NM 88349–0062, USA
3
Kiepenheuer-Institut für Sonnenphysik, Schöneckstr. 6, 79104 Freiburg, Germany e-mail: msig@kis.uni-freiburg.de
4
Astrophysikalisches Institut Potsdam, Telegrafenberg A27, 14473 Potsdam, Germany e-mail: kmuglach@aip.de
Corresponding author: A. Settele, asettele@rssd.esa.int
Received:
21
February
2002
Accepted:
28
May
2002
In order to look for magnetic field vector oscillations in sunspots
we used data measured with the Advanced Stokes Polarimeter at the Dunn Solar
Telescope. We analyzed two time series of 65 and 110 min
that were taken by scanning repeatedly a 62
field of view,
while obtaining the full Stokes vector in the lines FeI 630.15 nm and
630.25 nm. An inversion was carried out and a Fast Fourier Transform (FFT) analysis was used
to find oscillatory phenomena. We discuss possible unwanted effects that lead to apparent
magnetic field oscillations and find an average amplitude of (
) 5.8 G/0.23° rms by
excluding these effects, which also means that only 6% and 22% of the two
sunspot umbrae respectively remained for analysis. If we smooth the
power spectra over
pixels, all significant power disappears.
Key words: Sun: sunspots / Sun: magnetic fields / Sun: oscillations
© ESO, 2002
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