... \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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... image^13.5

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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