gtophase Help File

Computes an orbital phase for each event in input event file(s), and writes it to a FITS column in the file(s).

Usage: gtophase evfile scfile psrdbfile psrname ra dec

This tool operates on input event file(s) to compute an orbital phase for a photon arrival time of each event, and writes it to, by default, the PULSE_PHASE column of the event file(s). If necessary, this tool reads the spacecraft orbit file and performs the barycentric correction and the binary demodulation to each photon arrival time on the fly.

Example: gtophase

gtophase automatically extracts one or more ephemerides from an existing pulsar ephemerides database file. Unlike the similar gtpphase tool, there is no option for entering orbital ephemerides manually. This tool does not produce a separate output file, but operates directly on the input file in place. If execution is successful, the tool produces no textual output.

> gtophase evfile=fakepulsar_event.fits scfile=simscdata_1week.fits \
psrdbfile=bogus_pulsardb.fits psrname="PSR J1834-0010" \
ra=278.571942 dec=-0.180347

Pulsar Ephemeris Database File

A pulsar ephemeris database file is a FITS file or a text file in a Fermi-specific format, and contains a set of pulsar ephemerides to be used in a temporal analysis of Fermi data. When so specified, the pulsar analysis ScienceTools load pulsar ephemerides from pulsar ephemeris database files, and use them in their tasks. A pulsar ephemeris database file can be created, filtered, and combined by the gtpulsardb tool. Pulsar ephemerides for the Fermi LAT pulsars and timing models associated with various Fermi publications are also available on the FSSC's Gamma-ray Pulsar Timing Database page.