Zeeman Effect

Pieter Zeeman (1865-1943) Dutch Physicist born in Amsterdam. He makes his studies at the University of Leyden, where he will teach the physique of 1897 has 1900, date on which he is named professor at the university of Amsterdam. From 1908 it directs the Institute of Physics of this same city. In 1896 it discovers the Zeeman effect, confirming in experiments the predictions of its Master H. A. Lorentz and thus bringing a proof moreover in favour of the electromagnetic theory of the light. For this work, Lorentz and Zeeman, receive the first Nobel Prize of Physics in 1902.
Pieter Zeeman
  

Many metal lines of the solar spectrum appear, in the spots, widened or broken up into several lines.
Haul, which discovered this phenomenon, showed into 1908 that this decomposition of the lines is identical to that which one observes at the laboratory when the source of light is placed between the poles of a powerful electromagnet: it is the Zeeman effect.
The two typical cases simplest are that where one observes perpendicularly with the field (transverse Zeeman effect) and that where one observes in the axis of the champ(effet Zeeman logitudinal).
In transverse the Zeeman effect, one observes three lines polarized rectilignement.
The central line polarized in the direction of the field has even wavelength that while observing in the absence of this one.
 The two polarized side lines perpendicularly with the field are shifted compared to the central line of the value given by the formula below.
In longitudinal the Zeeman effect the central line disparait and two side lines, circularly polarized, are observed shifted on both sides:

E and m are respectively the load and the mass of the electron.
C the speed of the light, G the factor of Landé.
L the wavelength of the line observed in angström and B intensity of the magnetic field in gauss.
For the line of iron Fe (6302.5 Å) there is g=2.5.

According to an article of Xavier Luri (2003-10-23) of Boletín18 of the SEA.

Above the solar spectrum obtained with the SHG around the group of spots 0652 on 26 July 2004 as shown on the image opposite.
LE spectrum of the photospheric area except spot.
Image SOHO of the Sun in the visible one.

Preceding calculation gives, for the shift of +/- 3 pixels observed on the image with a dispersion of 0.038 Å/pixel, a magnetic field of approximately 2500 gauss.

Another example of a Zeeman effect.

Observation of NOAA 0822 of November 19, 2005 in the line Fe1 6302.5Å.

Spot NOAA 0828 on November 19, 2005 and the spectrum of the cut indicated by the white feature which indicates the position of the slit of the SHG.

It is seen clearly that the atmospheric lines, marked in green, are not widened... of course.

The lines of Fe1 do not completely offer the same aspect either in the magnetic field of the shade and the half-light of the spot.

The marked line of blue (Fe1 6297.8) has a factor of Landé G = 0.99.

The line marked of purple (Fe1 6301.5) has a factor of Landé g=1.67.

Their widening is less important than that of the marked line of red (Fe1 6302.5) which, with a factor of Landé g=2.49, the triplet of Zeeman in the half-light shows clearly lower.

The variation of the two side branches at the border shade-half-light is of 7 pixels approximately for the line Fe1 6302.5.
The Dl variation between the center of the line and each side component this line Fe1 6302.5 is of +/- 3.5 pixels is 0.126Å.
Celà gives a magnetic field of approximately 2700 gauss.

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