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Re: active region birth/death?

Dear Kano-san,

The PSF of the XRT at wavelengths longer than 60A is given by the
standard diffraction formula, using the width of the entrance annulus
as the aperture size.

For your temperature plot, please be aware that a filter ratio does not
give a meaningful temperature. I strongly suggest that you give it a
different name, such as "hardness". There is no quesiton that spurious
effects will appear if you take ratios using the Al/mesh combined with
any other filter.


Kano Ryouhei wrote:
> Dear Mark san,
> Do you have any quantitative information about the diameter of the
> gaussian core of PSF for the Al/Mesh filter and the other filters?
> I'm analyzing the temperature above the south pole limb taken during
> the eclipse on February 17, 2007. We used Al/Mesh and Ti/poly for the
> eclipse observation.
> Just on the limb, the temperature is high, but emission measure is low
> (See the attached PNG file). This may be a spurious structure caused
> by the diffuser image of Al/Mesh than the Ti/Poly image.
> The attached plots shows the several profiles in the south pole as the 
> function of the distance from the sun center (limb=1).
>   - The upper pannel shows the intensities: Al/Mesh(red) and
>     Ti/Poly(black).
>   - The center pannel shows the temperature.
>   - The lower pannel shows the emission measure.
> Regards,
> R.Kano
> ------------------------------------------------------------------------


Dr. Leon Golub; Harvard-Smithsonian Center for Astrophysics
60 Garden Street, Cambridge MA 02138
Ph: 617 495 7177; Fax: 617 496 7577
e-mail: lgolub@cfa.harvard.edu