Localization

Localization of transient

View the source on GitHub

Properties

* = required

Name	Type	Description
ra	number	ICRS right ascension [deg], utilizes the J2000 epoch and an equatorial coordinate system
dec	number	ICRS declination [deg], utilizes the J2000 epoch and an equatorial coordinate system
uncertainty_shape	enum	In what manner are the errors in RA and Dec defined - as circular, elliptical, or rectangular shapes Options: circle, ellipse, rectangle
ra_uncertainty	array	Uncertainty in RA [deg] with optional asymmetric errors, measured from the RA in the schema; respective ex: [r], [r1], [l1-, l1+]. For ellipse, ra axis is r1 or semi-major axis.
dec_uncertainty	array	Uncertainty in Dec [deg] with optional asymmetric errors, measured from the Dec in the schema; respective ex: [r2], [l2-, l2+]. Not reported if circular and Dec axis is r2 or semi-minor axis for ellipse.
position_angle	number	Anti-clockwise position angle from RA axis [deg]. Used if uncertainty_shape ellipse or rectangle is tilted w.r.t. standard (RA, Dec) coordinate.
containment_probability	number	Containment probability [dimensionless, 0-1], if not parsed, default is 0.9
systematic_included	boolean	Contains true when the systematic error is included and false when the systematic error is not included
instrument_phi	number	Instrument phi [deg]
instrument_theta	number	Instrument theta [deg]
instrument_semimajor_angle	number	Position angle of semi-major axis in instrument coordinates [deg]
healpix_url	string	URL of HEALPix localization probability file
healpix_file	string	Base 64 encoded content of a FITS file

Example

{
  "$schema": "https://gcn.nasa.gov/schema/v3.0.0/gcn/notices/core/Localization.schema.json",
  "ra": 120,
  "dec": 45,
  "uncertainty_shape": "ellipse",
  "ra_uncertainty": [
    -0.1,
    0.05
  ],
  "dec_uncertainity": [
    -0.2,
    0.5
  ],
  "position_angle": 0,
  "containment_probability": 0.95,
  "systematic_included": true,
  "instrument_phi": 90,
  "instrument_theta": 45,
  "instrument_semimajor_angle": 50,
  "healpix_url": "http://example.com/localization.fits",
  "healpix_file": "H4sIAAAAAAAAC......."
}