Background3D class represents a background rate per solid
angle as a function of reconstructed energy and detector coordinates
Its format specifications are available in BKG_3D.
This is the format in which IACT DL3 background rates are usually provided, as an example:
"""Plot the background rate from the HESS DL3 data release 1.""" import matplotlib.pyplot as plt from gammapy.irf import Background3D filename = "$GAMMAPY_DATA/hess-dl3-dr1/data/hess_dl3_dr1_obs_id_020136.fits.gz" bkg = Background3D.read(filename, hdu="BKG") bkg.peek() plt.show()
Background2D class represents a background rate per solid angle
as a function reconstructed energy and offset angle from the field of view center.
Its format specifications are available in BKG_2D.
You can produce a radially-symmetric background from a list of DL3 observations devoid of gamma-ray signal using the tutorial in background_model.html