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Structure: struct Scope

0 The set of templates is described by a structure struct Scope. This structure specifies a set of templates covering the mass range in parameter space described above and shown in Figure [*]. The fields of this structure are:
struct Scope {
int n_tmplt: This integer is the total number of templates needed to cover the region in parameter space. This is typically computed or set by template_grid().
float m_mn: The minimum mass of an object in the binary system, as described above, in solar masses.
float m_mx: The maximum mass of an object in the binary system, as described above, in solar masses. Together with the m_mn, this describes the region in parameter space covered by the set of templates.
float theta: The angle to the axis of the constant ambiguity ellipse whose axis has diameter dp. The angle is measured in radians counterclockwise from the $\tau_0$ axis. The range is $\theta \in
(-\pi/2,\pi/2)$.
float dp: The diameter along the ellipse (in sec). This is twice the radius $r_1$ given in Table [*]. The angle $\theta$ is measured to this axis.
float dq: The diameter along the ellipse (in sec). This is twice the radius $r_2$ given in Table [*].
float f_start: The frequency $f_0$ used in the definitions of $\tau_0$ and $\tau_1$ ([*],[*]); this is typically the frequency at which a binary chirp first enters the usable bandpass of the detector.
struct Template* templates: Pointer to the array of templates. This pointer is typically set by template_grid(), when it allocates the memory necessary to store the templates, and creates the necessary templates.
};

Note that a given constant ambiguity ellipse can be specified in either of two equivalent ways. For example the elllipse defined by

\begin{displaymath}
\theta = \pi/4, dp=1 {\rm\ msec}, dq=5 {\rm\ msec}
\end{displaymath} (9.2.194)

is completely equivalent to the ellipse
\begin{displaymath}
\theta = 5 \pi/4, dp=5 {\rm\ msec}, dq=1 {\rm\ msec}.
\end{displaymath} (9.2.195)

Either of these is acceptable. The literature frequently uses the second convention (angle measured to the major axis).


next up previous contents
Next: Function: tau_of_mass() Up: GRASP Routines: Template Bank Previous: Structure: struct Template   Contents
Bruce Allen 2000-11-19