5. Symbols and quantities used in formulae
A(Ej)
is the instrument effective area
(cm2), i.e. the content of
an OGIP format ARF file.
A lowercase a(E,x,y) indicates the
mirror effective area
b (and Bi)
b(E,B1,B2) indicates an adimensional correction for Burst Length dependent effects
as a function of BL thresholds Bi.
Count rate (cts/s alias cts/s/bin)
in PHA or PI channel (or bin) i
Photon input spectrum in
photon/cm2/s/keV
Ej indicates the input photon energy
(keV) on a discrete grid of j values
DeltaEj
indicates the width of the j-th grid elements.
Symbol epsilon indicates an adimensional quantum efficiency
f (and r)
f(E,r) indicates the fraction of PSF
falling within an extraction radius r.
G(E) indicates the Gaussian component of the
energy resolution.
Pij
is the pure redistribution matrix, which is an adimensional probability. This is the
content of an OGIP format RMF file.
Qij is a less customary form of the overall response matrix
which has the dimensions of cm2 keV. This is the form in which
a response matrix is stored in XAS format.
R(i,E) or Rij
indicates the overall response matrix (on a continuous or discrete energy
scale), which has the dimensions of an area
(cm2). This is the product of the
RMF and ARF files.
T(E) indicates the non-Gaussian tail component of the
energy resolution.
Symbol tau indicates the adimensional transmission of a component
like a filter,
grid or
window