Fermi Science Support Center

Data Released by the LAT Team During the First Year

The LAT team will release high-level data on transients and monitored sources consisting of flux (fluence) on various timescales, spectra, source position, and errors (including estimate of systematic errors) for all of these quantities; no release in phase 1 of individual reconstructed photon events.

Regarding gamma-ray bursts:

  • On-board detections released "immediately"
  • Expect refinement of parameters (e.g. source position, fluence in several energy bands) with subsequent processing on the ground; release information as soon as it is available.
  • For GRBs detected by GBM but not by LAT, a LAT upper limit will be released.
  • Data from LAT for a GRB detected by the GBM which leads to LAT detection after autonomous re-point will be released as soon as practical.

Regarding sources of interest:

  • Monitor and regularly release data, via the web, to the entire community, on list of sources of interest (proposed list here)
  • Update data weekly and include fluxes (daily to weekly averages), estimates of the spectra (weekly averages), position, and errors
  • Expected latency between receipt of Level 0 data at ISOC and availability of processed high-level data will improve with time. Nominal (best effort) schedule is:
    • First month of Phase 1; 2 weeks
    • Month 2-6; within 3 days
    • Months 6-12; within 1 day
    • Months 13-N; within 1 day (goal of 6 hours)

Regarding a preliminary source list (i.e., a preliminary "point source catalog"):

  • Release (on the web) a preliminary source list that includes sources detected with very high confidence (e.g., >20 sigma).
  • Release approximately 6 months after start of Phase 1
  • Include source position, average source flux, and the peak source flux and estimated spectral index between 100 MeV and 1 GeV.

The intention is to review periodically the list of monitored sources with the Fermi Users' Group and the Project Scientist.