Index: trunk/doc/release.2015/ps1.analysis/analysis.tex =================================================================== --- trunk/doc/release.2015/ps1.analysis/analysis.tex (revision 40609) +++ trunk/doc/release.2015/ps1.analysis/analysis.tex (revision 40610) @@ -116,8 +116,4 @@ % * real example of oversubtracted galaxy % \end{verbatim} - -\note{define psfQF, psfQFperfect} -\note{identify when each PM\_SOURCE\_MODE bit is raised} -\note{map PM\_SOURCE\_MODE bits from this paper to PSPS paper} The 1.8m Pan-STARRS\,1 telescope is located on the summit of Haleakala @@ -543,38 +539,37 @@ {\bf Flag Name} & {\bf Flag Value} & {\bf Description} \\ \hline -* PM\_SOURCE\_MODE\_PSFMODEL & 0x00000001 & Source fitted with a psf model (linear or non-linear) \\ -* PM\_SOURCE\_MODE\_EXTMODEL & 0x00000002 & Source fitted with an extended-source model \\ -* PM\_SOURCE\_MODE\_FITTED & 0x00000004 & Source fitted with non-linear model (PSF or EXT; good or bad) \\ -* PM\_SOURCE\_MODE\_FAIL & 0x00000008 & Fit (non-linear) failed (non-converge, off-edge, run to zero) \\ -* PM\_SOURCE\_MODE\_POOR & 0x00000010 & Fit succeeds, but low-SN, high-Chisq, or large (for PSF -- drop?) \\ -* PM\_SOURCE\_MODE\_PAIR & 0x00000020 & Source fitted with a double psf \\ -* PM\_SOURCE\_MODE\_PSFSTAR & 0x00000040 & Source used to define PSF model \\ -* PM\_SOURCE\_MODE\_SATSTAR & 0x00000080 & Source model peak is above saturation \\ -* PM\_SOURCE\_MODE\_BLEND & 0x00000100 & Source is a blend with other sources$^1$ \\ -* PM\_SOURCE\_MODE\_EXTERNAL & 0x00000200 & Source based on supplied input position \\ -* PM\_SOURCE\_MODE\_BADPSF & 0x00000400 & Failed to get good estimate of object's PSF \\ -* PM\_SOURCE\_MODE\_DEFECT & 0x00000800 & Source is thought to be a defect \\ -* PM\_SOURCE\_MODE\_SATURATED & 0x00001000 & Source is thought to be saturated pixels (bleed trail) \\ -* PM\_SOURCE\_MODE\_CR\_LIMIT & 0x00002000 & Source has crNsigma above limit \\ -* PM\_SOURCE\_MODE\_EXT\_LIMIT & 0x00004000 & Source has extNsigma above limit \\ -* PM\_SOURCE\_MODE\_MOMENTS\_FAILURE & 0x00008000 & could not measure the moments \\ -* PM\_SOURCE\_MODE\_SKY\_FAILURE & 0x00010000 & could not measure the local sky \\ -* PM\_SOURCE\_MODE\_SKYVAR\_FAILURE & 0x00020000 & could not measure the local sky variance \\ -x PM\_SOURCE\_MODE\_BELOW\_MOMENTS\_SN & 0x00040000 & moments not measured due to low S/N.$^1$ \\ -* PM\_SOURCE\_MODE\_BIG\_RADIUS & 0x00100000 & poor moments for small radius, try large radius \\ -* PM\_SOURCE\_MODE\_AP\_MAGS & 0x00200000 & source has an aperture magnitude \\ -* PM\_SOURCE\_MODE\_BLEND\_FIT & 0x00400000 & source was fitted as a blend \\ -* PM\_SOURCE\_MODE\_EXTENDED\_FIT & 0x00800000 & full extended fit was used \\ -* PM\_SOURCE\_MODE\_EXTENDED\_STATS & 0x01000000 & extended aperture stats calculated \\ -* PM\_SOURCE\_MODE\_LINEAR\_FIT & 0x02000000 & source fitted with the linear fit \\ -* PM\_SOURCE\_MODE\_NONLINEAR\_FIT & 0x04000000 & source fitted with the non-linear fit \\ -* PM\_SOURCE\_MODE\_RADIAL\_FLUX & 0x08000000 & radial flux measurements calculated \\ -x PM\_SOURCE\_MODE\_SIZE\_SKIPPED & 0x10000000 & size could not be determined$^2$ \\ - PM\_SOURCE\_MODE\_ON\_SPIKE & 0x20000000 & peak lands on diffraction spike \\ - PM\_SOURCE\_MODE\_ON\_GHOST & 0x40000000 & peak lands on ghost or glint \\ - PM\_SOURCE\_MODE\_OFF\_CHIP & 0x80000000 & peak lands off edge of chip \\ + PM\_SOURCE\_MODE\_PSFMODEL & 0x00000001 & Source fitted with a psf model (linear or non-linear) \\ + PM\_SOURCE\_MODE\_EXTMODEL & 0x00000002 & Source fitted with an extended-source model \\ + PM\_SOURCE\_MODE\_FITTED & 0x00000004 & Source fitted with non-linear model (PSF or EXT; good or bad) \\ + PM\_SOURCE\_MODE\_FAIL & 0x00000008 & Fit (non-linear) failed (non-converge, off-edge, run to zero) \\ + PM\_SOURCE\_MODE\_POOR & 0x00000010 & Fit succeeds, but low-SN, high-Chisq, or large (for PSF -- drop?) \\ + PM\_SOURCE\_MODE\_PAIR & 0x00000020 & Source fitted with a double psf \\ + PM\_SOURCE\_MODE\_PSFSTAR & 0x00000040 & Source used to define PSF model \\ + PM\_SOURCE\_MODE\_SATSTAR & 0x00000080 & Source model peak is above saturation \\ + PM\_SOURCE\_MODE\_BLEND & 0x00000100 & Source is a blend with other sources$^1$ \\ + PM\_SOURCE\_MODE\_EXTERNAL & 0x00000200 & Source based on supplied input position \\ + PM\_SOURCE\_MODE\_BADPSF & 0x00000400 & Failed to get good estimate of object's PSF \\ + PM\_SOURCE\_MODE\_DEFECT & 0x00000800 & Source is thought to be a defect \\ + PM\_SOURCE\_MODE\_SATURATED & 0x00001000 & Source is thought to be saturated pixels (bleed trail) \\ + PM\_SOURCE\_MODE\_CR\_LIMIT & 0x00002000 & Source has crNsigma above limit \\ + PM\_SOURCE\_MODE\_EXT\_LIMIT & 0x00004000 & Source has extNsigma above limit \\ + PM\_SOURCE\_MODE\_MOMENTS\_FAILURE & 0x00008000 & could not measure the moments \\ + PM\_SOURCE\_MODE\_SKY\_FAILURE & 0x00010000 & could not measure the local sky \\ + PM\_SOURCE\_MODE\_SKYVAR\_FAILURE & 0x00020000 & could not measure the local sky variance \\ + PM\_SOURCE\_MODE\_BELOW\_MOMENTS\_SN & 0x00040000 & moments not measured due to low S/N.$^1$ \\ + PM\_SOURCE\_MODE\_BIG\_RADIUS & 0x00100000 & poor moments for small radius, try large radius \\ + PM\_SOURCE\_MODE\_AP\_MAGS & 0x00200000 & source has an aperture magnitude \\ + PM\_SOURCE\_MODE\_BLEND\_FIT & 0x00400000 & source was fitted as a blend \\ + PM\_SOURCE\_MODE\_EXTENDED\_FIT & 0x00800000 & full extended fit was used \\ + PM\_SOURCE\_MODE\_EXTENDED\_STATS & 0x01000000 & extended aperture stats calculated \\ + PM\_SOURCE\_MODE\_LINEAR\_FIT & 0x02000000 & source fitted with the linear fit \\ + PM\_SOURCE\_MODE\_NONLINEAR\_FIT & 0x04000000 & source fitted with the non-linear fit \\ + PM\_SOURCE\_MODE\_RADIAL\_FLUX & 0x08000000 & radial flux measurements calculated \\ + PM\_SOURCE\_MODE\_SIZE\_SKIPPED & 0x10000000 & size could not be determined$^1$ \\ + PM\_SOURCE\_MODE\_ON\_SPIKE & 0x20000000 & peak lands on diffraction spike \\ + PM\_SOURCE\_MODE\_ON\_GHOST & 0x40000000 & peak lands on ghost or glint \\ + PM\_SOURCE\_MODE\_OFF\_CHIP & 0x80000000 & peak lands off edge of chip \\ \hline -\multicolumn{3}{l}{$^1$ not used for DR1 or DR2.} \\ -\multicolumn{3}{l}{$^2$ should not normally occur, does it?} \\ +\multicolumn{3}{l}{$^1$ Not used for DR1 or DR2.} \\ \hline \end{tabular} @@ -591,27 +586,29 @@ {\bf Flag Name} & {\bf Flag Value} & {\bf Description} \\ \hline -PM\_SOURCE\_MODE2\_DIFF\_WITH\_SINGLE & 0x00000001 & diff source matched to a single positive detection \\ -PM\_SOURCE\_MODE2\_DIFF\_WITH\_DOUBLE & 0x00000002 & diff source matched to positive detections in both images \\ -PM\_SOURCE\_MODE2\_MATCHED & 0x00000004 & source generated based on another image \\ -PM\_SOURCE\_MODE2\_ON\_SPIKE & 0x00000008 & $> 25\%$ of (PSF-weighted) pixels land on diffraction spike \\ -PM\_SOURCE\_MODE2\_ON\_STARCORE & 0x00000010 & $> 25\%$ of (PSF-weighted) pixels land on starcore \\ -PM\_SOURCE\_MODE2\_ON\_BURNTOOL & 0x00000020 & $> 25\%$ of (PSF-weighted) pixels land on burntool \\ -PM\_SOURCE\_MODE2\_ON\_CONVPOOR & 0x00000040 & $> 25\%$ of (PSF-weighted) pixels land on convpoor \\ -PM\_SOURCE\_MODE2\_PASS1\_SRC & 0x00000080 & source detected in first pass analysis \\ -PM\_SOURCE\_MODE2\_HAS\_BRIGHTER\_NEIGHBOR & 0x00000100 & peak is not the brightest in its footprint \\ -PM\_SOURCE\_MODE2\_BRIGHT\_NEIGHBOR\_1 & 0x00000200 & $flux_{\rm n} / (r^2 flux_{\rm p}) > 1$ \\ -PM\_SOURCE\_MODE2\_BRIGHT\_NEIGHBOR\_10 & 0x00000400 & $flux_{\rm n} / (r^2 flux_{\rm p}) > 10$ \\ -PM\_SOURCE\_MODE2\_DIFF\_SELF\_MATCH & 0x00000800 & positive detection match is probably this source \\ -PM\_SOURCE\_MODE2\_SATSTAR\_PROFILE & 0x00001000 & saturated source is modeled with a radial profile \\ -PM\_SOURCE\_MODE2\_ECONTOUR\_FEW\_PTS & 0x00002000 & too few points to measure the elliptical contour \\ -PM\_SOURCE\_MODE2\_RADBIN\_NAN\_CENTER & 0x00004000 & radial bins failed with too many NaN center bin \\ -PM\_SOURCE\_MODE2\_PETRO\_NAN\_CENTER & 0x00008000 & petrosian radial bins failed with too many NaN center bin \\ -PM\_SOURCE\_MODE2\_PETRO\_NO\_PROFILE & 0x00010000 & petrosian not build because radial bins missing \\ -PM\_SOURCE\_MODE2\_PETRO\_INSIG\_RATIO & 0x00020000 & insignificant measurement of petrosian ratio \\ -PM\_SOURCE\_MODE2\_PETRO\_RATIO\_ZEROBIN & 0x00040000 & petrosian ratio in the 0th bin (likely bad) \\ -PM\_SOURCE\_MODE2\_EXT\_FITS\_RUN & 0x00080000 & we attempted to run extended fits on this source \\ -PM\_SOURCE\_MODE2\_EXT\_FITS\_FAIL & 0x00100000 & at least one of the model fits failed \\ -PM\_SOURCE\_MODE2\_EXT\_FITS\_RETRY & 0x00200000 & one of the model fits was re-tried with new window \\ -PM\_SOURCE\_MODE2\_EXT\_FITS\_NONE & 0x00400000 & ALL of the model fits failed \\ + PM\_SOURCE\_MODE2\_DIFF\_WITH\_SINGLE & 0x00000001 & diff source matched to a single positive detection \\ + PM\_SOURCE\_MODE2\_DIFF\_WITH\_DOUBLE & 0x00000002 & diff source matched to positive detections in both images \\ + PM\_SOURCE\_MODE2\_MATCHED & 0x00000004 & source generated based on another image \\ + PM\_SOURCE\_MODE2\_ON\_SPIKE & 0x00000008 & $> 25\%$ of (PSF-weighted) pixels land on diffraction spike \\ + PM\_SOURCE\_MODE2\_ON\_STARCORE & 0x00000010 & $> 25\%$ of (PSF-weighted) pixels land on starcore \\ + PM\_SOURCE\_MODE2\_ON\_BURNTOOL & 0x00000020 & $> 25\%$ of (PSF-weighted) pixels land on burntool \\ + PM\_SOURCE\_MODE2\_ON\_CONVPOOR & 0x00000040 & $> 25\%$ of (PSF-weighted) pixels land on convpoor \\ + PM\_SOURCE\_MODE2\_PASS1\_SRC & 0x00000080 & source detected in first pass analysis \\ + PM\_SOURCE\_MODE2\_HAS\_BRIGHTER\_NEIGHBOR & 0x00000100 & peak is not the brightest in its footprint \\ + PM\_SOURCE\_MODE2\_BRIGHT\_NEIGHBOR\_1 & 0x00000200 & $flux_{\rm n} / (r^2 flux_{\rm p}) > 1$ \\ + PM\_SOURCE\_MODE2\_BRIGHT\_NEIGHBOR\_10 & 0x00000400 & $flux_{\rm n} / (r^2 flux_{\rm p}) > 10$ \\ + PM\_SOURCE\_MODE2\_DIFF\_SELF\_MATCH & 0x00000800 & positive detection match is probably this source \\ + PM\_SOURCE\_MODE2\_SATSTAR\_PROFILE & 0x00001000 & saturated source is modeled with a radial profile \\ + PM\_SOURCE\_MODE2\_ECONTOUR\_FEW\_PTS & 0x00002000 & too few points to measure the elliptical contour \\ + PM\_SOURCE\_MODE2\_RADBIN\_NAN\_CENTER & 0x00004000 & radial bins failed with too many NaN center bin \\ + PM\_SOURCE\_MODE2\_PETRO\_NAN\_CENTER & 0x00008000 & petrosian radial bins failed with too many NaN center bin$^1$ \\ + PM\_SOURCE\_MODE2\_PETRO\_NO\_PROFILE & 0x00010000 & petrosian not build because radial bins missing \\ + PM\_SOURCE\_MODE2\_PETRO\_INSIG\_RATIO & 0x00020000 & insignificant measurement of petrosian ratio \\ + PM\_SOURCE\_MODE2\_PETRO\_RATIO\_ZEROBIN & 0x00040000 & petrosian ratio in the 0th bin (likely bad) \\ + PM\_SOURCE\_MODE2\_EXT\_FITS\_RUN & 0x00080000 & we attempted to run extended fits on this source \\ + PM\_SOURCE\_MODE2\_EXT\_FITS\_FAIL & 0x00100000 & at least one of the model fits failed \\ + PM\_SOURCE\_MODE2\_EXT\_FITS\_RETRY & 0x00200000 & trailed asteroid model fit was re-tried with new window \\ + PM\_SOURCE\_MODE2\_EXT\_FITS\_NONE & 0x00400000 & ALL of the model fits failed \\ +\hline +\multicolumn{3}{l}{$^1$ Not used for DR1 or DR2.} \\ \hline \end{tabular} @@ -915,4 +912,18 @@ as locally insignificant. +Sometimes it is useful to know if a source has a near neighbor which +may be affecting the photometry. Three flag bits are used to identify +such possible situations. Peaks which are {\em not} the brightest peak +within a single footprint have the flag bit +\code{PM_SOURCE_MODE2_HAS_BRIGHTER_NEIGHBOR} set. This is a fairly +common situation. We also define the following ratio to compare the +flux of the bright source to the flux of a neighbor scaled by +intervening area: $R = \frac{f_{\rm n}}{r^2 f_{\rm p}}$ where $f_{\rm + n}$ is the flux of the brightest neighbor in the footprint, $f_{\rm + p}$ is the flux of the source of interest, and $r$ is the separation +between the two sources. If $R > 1$, the flag bit +\code{PM_SOURCE_MODE2_HAS_BRIGHT_NEIGHBOR_1} is set. If $R > 10$, the flag bit +\code{PM_SOURCE_MODE2_HAS_BRIGHT_NEIGHBOR_10} is set. + \subsubsection{Centroid and Higher-Order Moments} \label{sec:moments} @@ -1420,4 +1431,27 @@ values (see Section~\ref{sec:image.preparation}). +Several flag bits are raised based on statistics which are similar to +the \code{PSF_QF} measurement. First, \ippprog{psphot} calculates the +normalized, PSF-weighted fraction of pixels which are masked due to +one of the following four causes: a diffraction spike (\code{SPIKE}), +the core of a saturated star (\code{CORE}), burntool-subtracted region +(\code{BURNTOOL}), or a pixel for which, due to interpolation or +convolution, a significant fraction of the pixel flux comes from a +masked pixel. These masking conditions are all treated as ``suspect'' +by \ippprog{psphot}, which means they are {\em included} in the analysis of +the source pixels. However, since they may potentially affect the +photometry (or astrometry), it is useful to note of a source has a +non-trivial fraction of these poor mask pixels. If the normalized +PSF-weighted fraction of pixels masked due to any of these four +conditions exceeds 25\%, then one of the following bits is raised for +the corresponding condition: \code{PM_SOURCE_MODE2_ON_SPIKE}, +\code{PM_SOURCE_MODE2_ON_STARCORE}, +\code{PM_SOURCE_MODE2_ON_BURNTOOL}, +\code{PM_SOURCE_MODE2_ON_CONVPOOR}. In addition, the following flag +bits may also be raised if the central pixel +of a source lands on a pixel masked for a diffraction spike +(\code{PM_SOURCE_MODE_ON_SPIKE}), an optical ghost +(\code{PM_SOURCE_MODE_ON_GHOST}), or off the active pixels of the CCD (\code{PM_SOURCE_MODE_OFF_CHIP}). + \subsection{Bright Source Analysis} @@ -1472,5 +1506,7 @@ in the central regions are largely masked, because they are saturated. Thus in these cases, the psf-weighted masked fraction (see -Section~\ref{XX}) is generally quite low or 0.0. +Section~\ref{sec:psf.model.choice}) is generally quite low or 0.0. +Sources for which this radial profile is subtracted have the flag bit +\code{PM_SOURCE_MODE2_SATSTAR_PROFILE} set. % logRdel = 0.1 @@ -1877,8 +1913,26 @@ The sources which are measured in this faint-source stage are clearly low significance detections. The PV3 threshold for the bright source -analysis is a signal-to-noise of 20. The lower limit cutoff for the -faint source analysis in PV3 is a signal-to-noise of 5.0. Sources -detected in the faint source stage are fitted with the PSF model using -the linear, ensemble fitting process. +analysis is a signal-to-noise of 20. The flag bit +\code{PM_SOURCE_MODE2_PASS1_SRC} is raised for sources detected in +this initial analysis stage. The lower limit cutoff for the faint +source analysis in PV3 is a signal-to-noise of 5.0. Sources detected +in the faint source stage are fitted with the PSF model using the +linear, ensemble fitting process. + +In the \ippprog{psphotStack} version of the code, the 5 filter images +are processed together. In this case, any source which is detected in +at least two of the five filters are then also measured on the other +filter images in which it was not detected above the signal-to-noise +limit. The position in the other stack images is fixed based on the +pixel coordinates in the images in which the source was detected. +Detection in two filters is required in order to avoid excessive +forced photometry of spurious detections. There is an interesting +class of astronomical objects which are extremely red (\eg, brown +dwarfs and high-redshift quasars). Such sources are expected to be +detected only in the reddest filter (\yps). For the $3\pi$ PV3 +processing, we therefore also force the photometry in all filters for +sources which are only detected in \yps. All sources which are forced +on one image based on detections in other images have the flag bit +\code{PM_SOURCE_MODE2_MATCHED} set. \subsection{Extended Source Analysis} @@ -1987,4 +2041,13 @@ of the form $f_i(r_i)$. In this case, $f_i$ is effectively the surface brightness for each radius in instrumental counts per pixel. +If fewer than 4 radial surface-brightness values are available for the +analysis, the source is skipped and the flag bit +\code{PM_SOURCE_MODE2_ECONTOUR_FEW_PTS} is set. Some apparently +extended sources are in fact bright stars with central saturation. +These sources show up in this analysis as having many NAN-valued +pixels in the central regions. During the radial profile analysis, +such sources are flagged with the bit +\code{PM_SOURCE_MODE2_RADBIN_NAN_CENTER} and are skipped from the rest +of the analysis. The surface brightness profiles are then used to define the azimuthal @@ -2043,5 +2106,8 @@ max}$ for the annulus for which the Petrosian Ratio = 0.2, i.e., the point on the galaxy radial profile at which the surface brightness is -20\% of the average surface brightness at that point. +20\% of the average surface brightness at that point. If the profile +falls below the Petrosian ratio for the first radial bin, the flag bit +\code{PM_SOURCE_MODE2_PETRO_RATIO_ZEROBIN} is set to note that the +Petrosian radius may be poorly determined. We determine the Petrosian Radius for the galaxy by quadratic @@ -2054,6 +2120,9 @@ well as drops. We track the Petrosian Ratio until the value is no longer significant ($\sigma_{\rm Ratio} < 2 {\rm Ratio}$). If the -Petrosian Ratio drops below 0.2 for more than one radius, we choose -the largest such radius. +Petrosian ratio drops below 0.2 for more than one radius, we choose +the largest such radius. If the Petrosian ratio does not fall below +0.2 for any of the measured radii, the annulus for which the ratio +falls to the lowest (yet still significant) value. In such a case, +the flag bit \code{PM_SOURCE_MODE2_PETRO_INSIG_RATIO} is set. Once the Petrosian Radius has been determined, we can now measure the @@ -2064,5 +2133,8 @@ Petrosian flux is contained. Sources for which the Petrosian parameters are successfully measured have the flag bit -\code{PM_SOURCE_MODE_EXTENDED_STATS} set. +\code{PM_SOURCE_MODE_EXTENDED_STATS} set. Sources for which the Petrosian +parameters were attempted, but for which the radial profile analysis +failed have the flag bit +\code{PM_SOURCE_MODE2_PETRO_NO_PROFILE} set. @@ -2096,5 +2168,11 @@ (Section~\ref{sec:source.size}) or (b) the peak of the PSF profile was above the saturation limit for the chip \citep[see the discussion - in][regarding the masking of saturated pixels]{waters2017}. + in][regarding the masking of saturated pixels]{waters2017}. All +sources for which the extended source model fits were attempted the +flag bit \code{PM_SOURCE_MODE2_EXT_FITS_RUN} set. If any of the +attempted model fits failed, then the flag bit +\code{PM_SOURCE_MODE2_EXT_FITS_FAIL} is set. If all model fits +failed, then the flag bit \code{PM_SOURCE_MODE2_EXT_FITS_NONE} is +set. % \note{need a discussion of the detector saturation behavior?}