The Astrophysics Science Division (ASD) at NASA's Goddard Space Flight Center (GSFC) seeks a creative, innovative individual with strong teamwork and leadership skills to serve as Director of the High Energy Astrophysics Science Archive Research Center (HEASARC). This will be a permanent civil servant position. + Learn more.
Mixing Model Components
Mixing models perform transformations on the available spectra. The
spectra must be assigned to more than one data group in order have any
effect. Each data group is a “region” of the observation, and the
“mixing transformation” allows the model flux from one such
“region” to influence another region. Thus, these models, unlike all
the others, can be two-dimensional in effect. It follows that they
differ from all the other models in that the data must be read before
the model can be defined. In most cases also, the input data must
contain additional information in order to use the model. This
additional information can be in the form of the OGIP standard XFLT
keys, which allow a set of scalar real values, or in some cases
additional files to be read containing spatial information.
XSPEC will return error messages if the data are not loaded, not
compatible with the model (i.e. do not contain the required additional
information), loaded inconsistently with the use of the model (the
division of data into regions is incorrect, or data within a given
region fail consistency checks). It will also return error messages if
the data are subsequently changed to a set that violates these
consistency checks, and additionally remove the model definition.
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Last modified: Friday, 23-Aug-2024 13:20:40 EDT
The Astrophysics Science Division (ASD) at NASA's Goddard Space Flight Center (GSFC) seeks a creative, innovative individual with strong teamwork and leadership skills to serve as Director of the High Energy Astrophysics Science Archive Research Center (HEASARC). This will be a permanent civil servant position. + Learn more.
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