Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Image subtraction with non-constant kernel solutions   It is demonstrated that non-constant kernel solution, that can fit the
spatial variations of the kernel can be obtained with minimum computing time.
The CPU cost required with this new extension of the image subtraction method
is almost the same as for fitting constant kernel solution. The method is
demonstrated with a serie of Monte-Carlo images. Differential PSF variations
and differential rotation between the images are simulated. It is shown that
this new method is able to achieve an optimal results even in these difficult
cases. It is clear that the most frequents instrumental problems are
automatically corrected by the method. It is also demonstrated that the method
does not suffer problems with under-sampling of the images. To conclude the
method is applied to real images of crowded field. It is proved that much
larger sub-areas of the images can be used for the fit, while keeping the same
accuracy in the subtracted image. This result is especially important in case
of variables located in low density fields, like the Huchra lens. Many other
useful applications of the method are possible for major astrophysical
problems. For instance supernovas search should benefit the method, but other
applications like Cepheids surveys in other galaxies should also find some
advantage in using the method. Many other applications will certainly show-up,
since variability search is a major issue in astronomy.

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The categories of this paper are: eess
32
The categories of this paper are: atom-ph
4
The categories of this paper are: cond-mat
24
The categories of this paper are: dg-ga
33
The categories of this paper are: plasm-ph
16
The categories of this paper are: stat
15
The categories of this paper are: nucl-ex
3
The categories of this paper are: physics
18
The categories of this paper are: econ
20
The categories of this paper are: acc-phys
8
The categories of this paper are: hep-ex
7
The categories of this paper are: hep-th
28
The categories of this paper are: alg-geom
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The categories of this paper are: nucl-th
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The categories of this paper are: supr-con
30
The categories of this paper are: q-alg