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Relative merits of the algorithms under consideration

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Presentation on theme: "Relative merits of the algorithms under consideration"— Presentation transcript:

1 Relative merits of the algorithms under consideration
Source detection and catalog pipeline architecture Relative merits of the algorithms under consideration Review of selection criteria and time scale for selection '3D' methods (map + energy, map + time) Inclusion of a 'source finder' tool into the Science Analysis Environment ? Pipeline script, interfaces between the successive stages Operational issues (scheduler, database, computational requirements)

2 Relative merits of the algorithms under consideration
Several algorithms have been proposed (likehood, several Wavelet methods, Bayesian blocks, …). We need to have a good understanding on the quality of each of these methods. Some of them are not included in the pipeline and some works need to be done if want to use them. The optimal filter has the advantage to produce a significance map. Such a map could also be derived from the wavelet coefficients but in relatively heuristic way. It is clear that whatever the selected method for source detection, a maximum likehood should be used to estimate the other parameters (photometry, …). It may happen that several algorithms could be useful. For instance, for a quick look analysis, we need a fast method, but not necessary optimal.

3 Review of selection criteria and time scale for selection
For the selection of the detection method, we agreed that it would be useful to first make a set of tests on toy models and make an evaluation of the different algorithm. Then we can decide which algorithms should be included in the pipeline and tested in a more realistic way. Two data sets already exist. A third one is needed, which would allows us to see the resolved power of each method.

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5 '3D' methods (map + energy, map + time)
X Y Z We have discussed the need of 3D tools (spatial + time or spatial + energies) and 4D tools (spatial + time + energy). It seems that 4D analysis is not needed. For temporal analysis, we can consider a given energy band and make the temporal analysis for this band only. Several tools/idea have been discussed. The Voronoi methods could be used, but we have to figure out how to use the output of the Voronoi method. Gino has a project of developping a 3D mexican hat. I have reported some ongoing effort to develop a 3D wavelet analysis for GLAST.

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7 z = 0 z = 29

8 Inclusion of a 'source finder' tool into the Science Analysis Environment ? NO
Pipeline script, interfaces between the successive stages. The best is to use the GLAST catalog format. Operational issues (scheduler, database, computational requirements) The likehood method is not fast enough for finding the source positions but Jim has some idea to spead up the algorithm. There is a need to build a tool which create a diffuse emission model of a part of the sky.


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