Changeset 39845 for trunk/doc/release.2015/ps1.analysis/analysis.tex

Timestamp:

Dec 11, 2016, 11:56:48 AM (10 years ago)

Author:

eugene

Message:

updates to analysis and calibration

File:

• trunk/doc/release.2015/ps1.analysis/analysis.tex (modified) (12 diffs)

trunk/doc/release.2015/ps1.analysis/analysis.tex

@@ -410 +410 @@
 The variance image, if not supplied is constructed by default from the
 flux image using the configuration supplied values of \code{GAIN} and
-\code{READ\_NOISE} to calculate the appropriate Poisson statistics for
+\code{READ_NOISE} to calculate the appropriate Poisson statistics for
 each pixel.  In this case, the image is assumed to represent the
 readout from a single detector, with well-defined gain and read noise
@@ -444 +444 @@
 image.  The background image and the background standard deviation
 image are kept in memory from which the values of \code{SKY} and
-\code{SKY\_SIGMA} are calculated for each object in the output catalog.
+\code{SKY_SIGMA} are calculated for each object in the output catalog.
 
 \subsection{Initial Object Detection}
@@ -458 +458 @@
 the covariance, if known. At this stage, the goal is only to detect
 the brighter sources, above a user defined S/N limit (configuration
-keyword: \code{PEAKS\_NSIGMA\_LIMIT}).  A maximum of
-\code{PEAKS\_NMAX} are found at this stage.  The detection efficiency
+keyword: \code{PEAKS_NSIGMA_LIMIT}).  A maximum of
+\code{PEAKS_NMAX} are found at this stage.  The detection efficiency
 for the brighter sources is not strongly dependent on the form of this
 smoothing function.
@@ -546 +546 @@
 {\em key col} for this peak (as used in topographic descriptions of a
 mountain).  If the key col for a given peak is less than
-\code{FOOTPRINT\_CULL\_NSIGMA\_DELTA} (4.0) sigmas below the peak of
+\code{FOOTPRINT_CULL_NSIGMA_DELTA} (4.0) sigmas below the peak of
 interest, the peak is considered to be {\em locally insignificant} and
 removed from the list of possible detections.  In the vicinity of a
@@ -581 +581 @@
 to find a value of $\sigma_W$ for which $f$ is expected to be 0.65.
 \note{what is the expected ratio of $\sigma_x$ to the true value?}.
-We call this value the \code{MOMENTS\_GAUSS\_SIGMA}.  We use an
-aperture with a radius of \code{PSF\_MOMENTS\_RADIUS} = 4$\times$
-\code{MOMENTS\_GAUSS\_SIGMA} to select the pixels for the measurement.
-
-Once \code{PSF\_MOMENTS\_SIGMA} has been determined, moments are
+We call this value the \code{MOMENTS_GAUSS_SIGMA}.  We use an
+aperture with a radius of \code{PSF_MOMENTS_RADIUS} = 4$\times$
+\code{MOMENTS_GAUSS_SIGMA} to select the pixels for the measurement.
+
+Once \code{PSF_MOMENTS_SIGMA} has been determined, moments are
 measured as defined below.  
 
@@ -615 +615 @@
 
 If the measured centroid coordinates ($x_0, y_0$) differs from the
-peak coordinates be a large amount (\code{MOMENT\_RADIUS}), then the
+peak coordinates be a large amount (\code{MOMENT_RADIUS}), then the
 peak is identified as being of poor quality and is rejected.  In
 both of these cases, it is likely that the `peak' was identified in a
@@ -638 +638 @@
 limited at the low and high ends by $R_{\rm min} < M_r < R_{\rm max}$
 where $R_{\rm min}$ is the first radial moment of the PSF stars, or
-0.75$\times$ \code{MOMENTS\_GAUSS\_SIGMA} if that cannot be
-determined.  $R_{\rm max}$ is set to \code{PSF\_MOMENTS\_RADIUS}, the
+0.75$\times$ \code{MOMENTS_GAUSS_SIGMA} if that cannot be
+determined.  $R_{\rm max}$ is set to \code{PSF_MOMENTS_RADIUS}, the
 size of the moments aperture.
 
@@ -731 +731 @@
 registered as part of the model function code.  Another function is
 then used to return the appropriate function for a specific model
-type.  For example, the \code{psModelLookup\_GetFunction} will return
+type.  For example, the \code{psModelLookup_GetFunction} will return
 the \code{psModelLookup} function for a given model type.  This
 mechanism makes it very easy to add new model functions into the
@@ -756 +756 @@
 their peaks, as well as an approximate signal-to-noise ratio.  All
 objects with a S/N ratio greater than a user-defined parameter
-(\code{PSF\_SHAPE\_NSIGMA} ???) are selected by PSPhot, though objects
+(\code{PSF_SHAPE_NSIGMA} ???) are selected by PSPhot, though objects
 which have more than a certain number of saturated pixels are excluded
 at this stage.  PSPhot then examines the 2-D plane of $\sigma_x,
@@ -1014 +1014 @@
 
 PSPhot will use the user-selected galaxy model to attempt the galaxy
-model fits.  In the configuration system, the keyword \code{GAL\_MODEL}
+model fits.  In the configuration system, the keyword \code{GAL_MODEL}
 is set to the model of interest.  All suspected extended objects are
 fitted with the model, allowing all of the parameters to float.  The
@@ -1146 +1146 @@
 value for the ApResid scatter is then used by PSPhot as the best PSF
 model for this image.  The number of models to be tested is specified
-by the configuration keyword \code{PSF\_MODEL\_N}.  The configuration
-variables \code{PSF\_MODEL\_0}, \code{PSF\_MODEL\_1}, through
-\code{PSF\_MODEL\_N - 1} specify the names of the models which should be
+by the configuration keyword \code{PSF_MODEL_N}.  The configuration
+variables \code{PSF_MODEL_0}, \code{PSF_MODEL_1}, through
+\code{PSF_MODEL_N - 1} specify the names of the models which should be
 tested.
 
@@ -1198 +1198 @@
 
 The surface brightness values are sampled at a number of radial
-annuli, with the radii defined in the configuration ({\tt
-  RADIAL.ANNULAR.BINS.LOWER \& RADIAL.ANNULAR.BINS.UPPER}).  For each
-source, the resulting surface brightness profile is saved in the
-output cmf-file as an N-element value in the FITS table ({\tt
-  PROF\_SB}).  The flux at each radial position and the fill-factor
-(fraction of pixels used to the total possible) as also saved as
-equal-length vectors in the FITS table ({\tt PROF\_FLUX and
-  PROF\_FILL}).  The values of the radial bins are saved in the cmf
-header ({\tt RMIN\_NN, RMAX\_NN}).
+annuli, with the radii defined in the configuration
+(\code{RADIAL.ANNULAR.BINS.LOWER} \&
+\code{RADIAL.ANNULAR.BINS.UPPER}).  For each source, the resulting
+surface brightness profile is saved in the output cmf-file as an
+N-element value in the FITS table (\code{PROF_SB}).  The flux at each
+radial position and the fill-factor (fraction of pixels used to the
+total possible) as also saved as equal-length vectors in the FITS
+table (\code{PROF_FLUX} and \code{PROF_FILL}).  The values of the
+radial bins are saved in the cmf header (\code{RMIN_NN},
+\code{RMAX_NN}).
 
 \note{these profiles are not saved in PSPS}