PulsarAstronomy.net
The Pulsar Astronomy Network

(:pagelist link=Category.Subject list=normal:).

Unfortunately there are very few adopted standards for any type of data.

!!Ephermerdies
The most simple pulsar data format is the ephemeris.
This is the parameters used in the timing model.
Ephemerdies come as text files with a .eph or .par extension.

There appears to be no formal specification of what parameters are used in these files, although a loose standard has developed, with the following common parameters.


|| border=1
||!Parameter ||!Units ||!Description ||!Aliases
|| PSRJ || String || Pulsar JName ||
|| RAJ || sex-hr || Right Asscention (J2000) ||
|| DECJ || sex-deg|| Declination (J2000) ||
|| PEPOCH || MJD || Period Epoch ||
|| F0 || Hz || Fundemental frequency of the PSR || F (sometimes P/P0, the period)
|| F1 || Hz/s || First derivitive of rotational freq ||
|| F2 || Hz/s/s || Second derivitive of rotational freq ||
|| POSEPOCH || MJD || Position Epoch ||
|| DM || pc/cm3 || Dispersion Measure ||
|| START || MJD || Time the eph is valid from ||
|| FINISH || MJD || Time the eph is valid till ||
|| BINARY || String || The binary model used (if any) ||
|| EPHVER || Integer|| The eph version ||


The parameters for the binary motion are dependent on the binary model used.

For the '''BT''' model:

|| border=1
||!Parameter ||!Units ||!Description ||!Aliases
|| A1 || ltsec || projected semimajor axis ||
|| ECC || || Eccentricity of the orbit || E
|| T0 || MJD || Epoch of periastron ||
|| PB || days || Orbital Period ||
|| OM || deg || Longitude of Periastron ||


The files are tab or whitespace seperated with a single line for each keyword.
Note that exponentials can be writen with a standard 'e' notation, or the rather more strange 'D' notation.
e.g.
PSRJ 1722-2210
F0 1.23234234
F1 2.34567D-02


The files produced by tempo and psrtime should be compatable.
tempo2 can read tempo files, with the -tempo1 switch.
tempo2 files are not backwards compatible to psrtime.




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|| !Parameter || !Units || !Description || !Aliases

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