... \marx\2.1
MARX is a suite of programs created by the MIT/CXC group and designed to enable the user to simulate the on-orbit performance of the Chandra X-ray Observatory. Further information is available at http://space.mit.edu/CXC/MARX/.
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... dataset.4.1
Since a source could be missed if it straddles the border between regions of different blocking factors, each celldetect pass actually extends a bit into the previously-analyzed region. Occasionally this leads to two detections of the same source, but such cases are automatically identified (see the output source list columns DOUBLE and DOUBLE_ID, discussed in Chapter 7).
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... file:7.1
Items marked with "$ \dagger$" are not yet calculated by celldetect ; these columns in the output file will contain zeros.
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... "sliding-box''13.1
The method used in the Chandra source detection routine celldetect.
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... simple.13.2
The current version of wtransform works only with binned images, though it may be updated in the future to also work with event lists.
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... maximum.13.3
By writing $ C$ in this way, we also note that the term $ <NW{\ast}D>$, which is $ \leq$ 0 by definition, acts to subtract the contribution of the local background around the clump from the value of $ C$. We return to this point in §13.3.
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... FOV.13.4
We "tile over" regions where the normalized background has been set to zero. We subdivide the image into smaller and smaller boxes: if in any one box the percentage of non-zero pixels is less than 20%, wtransform determines the average value in those pixels and assigns that value to the other pixels of the box. "Extrapolation" beyond the FOV is currently accomplished by simple mirror-image reflection.
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... image13.5
The normalized background image is input by the user, or a default image is constructed from images made at each scale by wtransform (see Appendix 13.8).
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... -6.9.13.6
Small values of $ q_{i,j}$ occur even when there are no counts in the negative annulus of the wavelet function because the FFT is inexact.
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... minimal.13.7
A new method of determining the variance, based upon a suggestion by Kolaczyk (private communication), is being tested and may be used in future versions of wrecon .
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