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Please note that Masa et al maintain a "pulsar tools do-list" at  http://glast.gsfc.nasa.gov/ssc/dev/psr_tools/status.html .

A discussion on how to resolve bug and issue of the Tools 'gtpphase' and 'gtbary' is at: gtpphase & gtbary

The topics

In approximate order of increasing pain-to-gain:

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Even if we agree that in general and in most cases we'll want piecewise timing solutions, allow me to insist that the pain-to-gain of adding higher-order derivatives to both the D4 and to gtpphase etc is small. It's just some columns, and some higher-order terms in the Taylor series. We would then have the flexibility of using ST's with ephemerides found in the literature. The alternatives are a) to track down the author and convince him/her to re-generate 3-parameter timing solutions for the epochs that suit us, or b) extract the dates from the FT1 file and use TEMPO instead of ST's.

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 Further exchanges lead Dave S to this summary:

The pulsar Science Tools in their present state work fine *IF* the user is careful to keep the data in separate FT1 files that are more or less matched to the validity periods of the D4 lines he/she uses.

In practice: Joe User goes to the GSSC Data Portal and enters ra,dec,tstart,tstop into the web interface (or other request mechanism).

 If Joe User is pulsar-savvy, he'll have a list of (tstart,tstop) pairs that he got from the D4. He'll get one fits file per pair. Then he'll stack gamma phases nicely.

 If Joe User is naive, he'll ask for tstart=launch and tstop=now, he'll get one fits file, ST will treat those many months of data with a single ephemeris, and he'll wonder why he sees no pulsations.