Changeset 40602 for trunk/doc/release.2015/ps1.calibration/calibration.tex
- Timestamp:
- Jan 22, 2019, 4:01:20 AM (7 years ago)
- File:
-
- 1 edited
Legend:
- Unmodified
- Added
- Removed
-
trunk/doc/release.2015/ps1.calibration/calibration.tex
r40597 r40602 116 116 \section{Introduction}\label{sec:intro} 117 117 118 \note{list all ID\_IMAgE, ID\_MEAS, ID\_OBJ, ID\_SECF flags from libdvo/include/dvo.h and identify how they are set; make tables} 119 120 118 121 From May 2010 through March 2014, the Pan-STARRS Science Consortium 119 122 used the 1.8m \PSONE\ telescope to perform a set of wide-field science … … 663 666 that into the master PV3 $3\pi$ DVO database. 664 667 668 The master DVO database is used to perform the full photometric and 669 astrometric calibration of the data. During these analysis steps, a 670 wide variety of conditions are noted for individual measurements, for 671 the objects (either as a whole or for specific filters) and for the 672 images. A set of bit-valued flags are used in the database to record 673 these conditions. 674 % 675 Table~\ref{tab:measure_mask_values} lists the flags specific to 676 individual measurements. These values are stored in the DVO database in the 677 field \code{Measure.dbFlags} and exposed in the public database \citep[PSPS][]{flewelling2017} 678 in the fields \code{Detection.infoFlag3}, 679 \code{StackObjectThin.XinfoFlag3} (where \code{X} is one of 680 {$grizy$}), and \code{ForcedWarpMeasurement.FinfoFlag3}. 681 % 682 Table~\ref{tab:secf_mask_values} lists the flags which are set for 683 each filter for individual objects in the database. These values are 684 recorded in the DVO database field \code{SecFilt.flags} and are 685 exposed in PSPS in the fields 686 \code{MeanObject.XFlags} and \code{StackObjectThin.XinfoFlag4}, where 687 \code{X} in both cases is one of {$grizy$}. 688 % 689 Table~\ref{tab:tab:object_mask_values} lists the flags specific to an 690 object as a whole. These values are stored in the DVO database field 691 \code{Average.flags} and are exposed in PSPS in 692 the field \code{MeanObject.objInfoFlag}. 693 % 694 Table~\ref{tab:image_mask_values} lists the flags raised for images. 695 These flags are stored in the DVO database field \code{Image.flags} 696 and are exposed in PSPS in the field \code{ImageMeta.qaFlags}. 697 % 698 The type of conditions which are recorded by these bits range from 699 information about the presence of external measurements (e.g., 2MASS 700 or WISE) to determinations of good or bad quality measurements for 701 astrometry or photometry. In the sections below, these flag values in 702 these tables are described where appropriate. Note that some of the 703 listed bits are either ephemeral (used internal to specific programs) 704 or are not relevant to the current DR2 analysis and reserved for 705 future use. 706 707 \begin{table*} 708 \begin{center} 709 \footnotesize 710 \caption{\label{tab:measure_mask_values} Per-Measurement Flag Bit Values} % \vspace{-0.5cm} 711 \begin{tabular}{lcl} 712 \hline 713 \hline 714 {\bf Bit Name} & {\bf Bit Value} & {\bf Description} \\ 715 \hline 716 ID\_MEAS\_NOCAL & 0x00000001 & detection ignored for this analysis (photcode, time range) -- internal only \\ 717 ID\_MEAS\_POOR\_PHOTOM & 0x00000002 & detection is photometry outlier (not used PV3) \\ 718 ID\_MEAS\_SKIP\_PHOTOM & 0x00000004 & detection was ignored for photometry measurement (not used PV3) \\ 719 ID\_MEAS\_AREA & 0x00000008 & detection near image edge (not used PV3) \\ 720 ID\_MEAS\_POOR\_ASTROM & 0x00000010 & detection is astrometry outlier \\ 721 ID\_MEAS\_SKIP\_ASTROM & 0x00000020 & detection was ignored for astrometry measurement \\ 722 ID\_MEAS\_USED\_OBJ & 0x00000040 & detection was used during update objects \\ 723 ID\_MEAS\_USED\_CHIP & 0x00000080 & detection was used during update chips (not saved PV3) \\ 724 ID\_MEAS\_BLEND\_MEAS & 0x00000100 & detection is within radius of multiple objects \\ 725 ID\_MEAS\_BLEND\_OBJ & 0x00000200 & multiple detections within radius of object \\ 726 ID\_MEAS\_WARP\_USED & 0x00000400 & measurement used to find mean warp photometry \\ 727 ID\_MEAS\_UNMASKED\_ASTRO & 0x00000800 & measurement was not masked in final astrometry fit \\ 728 ID\_MEAS\_BLEND\_MEAS\_X & 0x00001000 & detection is within radius of multiple objects across catalogs \\ 729 ID\_MEAS\_ARTIFACT & 0x00002000 & detection is thought to be non-astronomical \\ 730 ID\_MEAS\_SYNTH\_MAG & 0x00004000 & magnitude is synthetic \\ 731 ID\_MEAS\_PHOTOM\_UBERCAL & 0x00008000 & externally-supplied zero point from ubercal analysis \\ 732 ID\_MEAS\_STACK\_PRIMARY & 0x00010000 & this stack measurement is in the primary skycell \\ 733 ID\_MEAS\_STACK\_PHOT\_SRC & 0x00020000 & this measurement supplied the stack photometry \\ 734 ID\_MEAS\_ICRF\_QSO & 0x00040000 & this measurement is an ICRF reference position \\ 735 ID\_MEAS\_IMAGE\_EPOCH & 0x00080000 & this measurement is registered to the image epoch (not tied to ref catalog epoch) \\ 736 ID\_MEAS\_PHOTOM\_PSF & 0x00100000 & this measurement is used for the mean psf mag \\ 737 ID\_MEAS\_PHOTOM\_APER & 0x00200000 & this measurement is used for the mean ap mag \\ 738 ID\_MEAS\_PHOTOM\_KRON & 0x00400000 & this measurement is used for the mean kron mag \\ 739 ID\_MEAS\_MASKED\_PSF & 0x01000000 & this measurement is masked based on IRLS weights for mean psf mag \\ 740 ID\_MEAS\_MASKED\_APER & 0x02000000 & this measurement is masked based on IRLS weights for mean ap mag \\ 741 ID\_MEAS\_MASKED\_KRON & 0x04000000 & this measurement is masked based on IRLS weights for mean kron mag \\ 742 ID\_MEAS\_OBJECT\_HAS\_2MASS & 0x10000000 & measurement comes from an object with 2mass data \\ 743 ID\_MEAS\_OBJECT\_HAS\_GAIA & 0x20000000 & measurement comes from an object with gaia data \\ 744 ID\_MEAS\_OBJECT\_HAS\_TYCHO & 0x40000000 & measurement comes from an object with tycho data \\ 745 \hline 746 \end{tabular} 747 \end{center} 748 \end{table*} 749 750 \begin{table*} 751 \begin{center} 752 \footnotesize 753 \caption{\label{tab:secf_mask_values} Relphot Per-Filter Info Flag Bit Values} % \vspace{-0.5cm} 754 \begin{tabular}{lcl} 755 \hline 756 \hline 757 {\bf Bit Name} & {\bf Bit Value} & {\bf Description} \\ 758 \hline 759 ID\_SECF\_STAR\_FEW & 0x00000001 & Used within relphot: skip star \\ 760 ID\_SECF\_STAR\_POOR & 0x00000002 & Used within relphot: skip star \\ 761 ID\_SECF\_USE\_SYNTH & 0x00000004 & Synthetic photometry used in average measurement \\ 762 ID\_SECF\_USE\_UBERCAL & 0x00000008 & Ubercal photometry used in average measurement \\ 763 ID\_SECF\_HAS\_PS1 & 0x00000010 & PS1 photometry used in average measurement \\ 764 ID\_SECF\_HAS\_PS1\_STACK & 0x00000020 & PS1 stack photometry exists \\ 765 ID\_SECF\_HAS\_TYCHO & 0x00000040 & Tycho photometry used for synth mags \\ 766 ID\_SECF\_FIX\_SYNTH & 0x00000080 & Synth mags repaired with zpt map \\ 767 ID\_SECF\_RANK\_0 & 0x00000100 & Average magnitude uses rank 0 values \\ 768 ID\_SECF\_RANK\_1 & 0x00000200 & Average magnitude uses rank 1 values \\ 769 ID\_SECF\_RANK\_2 & 0x00000400 & Average magnitude uses rank 2 values \\ 770 ID\_SECF\_RANK\_3 & 0x00000800 & Average magnitude uses rank 3 values \\ 771 ID\_SECF\_RANK\_4 & 0x00001000 & Average magnitude uses rank 4 values \\ 772 ID\_SECF\_OBJ\_EXT\_PSPS & 0x00002000 & In PSPS ID\_SECF\_OBJ\_EXT is saved here so it fits within 16 bits \\ 773 ID\_SECF\_STACK\_PRIMARY & 0x00004000 & PS1 stack photometry includes a primary skycell \\ 774 ID\_SECF\_STACK\_BESTDET & 0x00008000 & PS1 stack best measurement is a detection (not forced) \\ 775 ID\_SECF\_STACK\_PRIMDET & 0x00010000 & PS1 stack primary measurement is a detection (not forced) \\ 776 ID\_SECF\_STACK\_PRIMARY\_MULTIPLE & 0x00020000 & PS1 stack object has multiple primary measurements \\ 777 ID\_SECF\_HAS\_SDSS & 0x00100000 & This photcode has SDSS photometry \\ 778 ID\_SECF\_HAS\_HSC & 0x00200000 & This photcode has HSC photometry \\ 779 ID\_SECF\_HAS\_CFH & 0x00400000 & This photcode has CFH photometry (mostly Megacam) \\ 780 ID\_SECF\_HAS\_DES & 0x00800000 & This photcode has DES photometry \\ 781 ID\_SECF\_OBJ\_EXT & 0x01000000 & Extended in this band \\ 782 \hline 783 \end{tabular} 784 \end{center} 785 \end{table*} 786 787 \begin{table*} 788 \begin{center} 789 \footnotesize 790 \caption{\label{tab:object_mask_values} Per-Object Flag Bit Values} % \vspace{-0.5cm} 791 \begin{tabular}{lcl} 792 \hline 793 \hline 794 {\bf Bit Name} & {\bf Bit Value} & {\bf Description} \\ 795 \hline 796 ID\_OBJ\_FEW & 0x00000001 & used within relphot: skip star \\ 797 ID\_OBJ\_POOR & 0x00000002 & used within relphot: skip star \\ 798 ID\_OBJ\_ICRF\_QSO & 0x00000004 & object IDed with known ICRF quasar (may have ICRF position measurement) \\ 799 ID\_OBJ\_HERN\_QSO\_P60 & 0x00000008 & identified as likely QSO \citep{2016ApJ...817...73H}, $P_{\rm QSO} \geq 0.60$ \\ 800 ID\_OBJ\_HERN\_QSO\_P05 & 0x00000010 & identified as possible QSO \citep{2016ApJ...817...73H}, $P_{\rm QSO} \geq 0.05$ \\ 801 ID\_OBJ\_HERN\_RRL\_P60 & 0x00000020 & identified as likely RR Lyra \citep{2016ApJ...817...73H}, $P_{\rm RRLyra} \geq 0.60$ \\ 802 ID\_OBJ\_HERN\_RRL\_P05 & 0x00000040 & identified as possible RR Lyra \citep{2016ApJ...817...73H}, $P_{\rm RRLyra} \geq 0.05$ \\ 803 ID\_OBJ\_HERN\_VARIABLE & 0x00000080 & identified as a variable by \cite{2016ApJ...817...73H} \\ 804 ID\_OBJ\_TRANSIENT & 0x00000100 & identified as a non-periodic (stationary) transient \\ 805 ID\_OBJ\_HAS\_SOLSYS\_DET & 0x00000200 & identified with a known solar-system object (asteroid or other) \\ 806 ID\_OBJ\_MOST\_SOLSYS\_DET & 0x00000400 & most detections from a known solar-system object \\ 807 ID\_OBJ\_LARGE\_PM & 0x00000800 & star with large proper motion \\ 808 ID\_OBJ\_RAW\_AVE & 0x00001000 & simple weighted average position was used (no IRLS fitting) \\ 809 ID\_OBJ\_FIT\_AVE & 0x00002000 & average position was fitted \\ 810 ID\_OBJ\_FIT\_PM & 0x00004000 & proper-motion model was fitted \\ 811 ID\_OBJ\_FIT\_PAR & 0x00008000 & full parallax and proper-motion model was fitted \\ 812 ID\_OBJ\_USE\_AVE & 0x00010000 & average position used (no proper-motion or parallax) \\ 813 ID\_OBJ\_USE\_PM & 0x00020000 & proper motion fit used (no parallax) \\ 814 ID\_OBJ\_USE\_PAR & 0x00040000 & full fit with proper motion and parallax \\ 815 ID\_OBJ\_NO\_MEAN\_ASTROM & 0x00080000 & mean astrometry could not be measured \\ 816 ID\_OBJ\_STACK\_FOR\_MEAN & 0x00100000 & stack position used for mean astrometry \\ 817 ID\_OBJ\_MEAN\_FOR\_STACK & 0x00200000 & mean astrometry could not be measured \\ 818 ID\_OBJ\_BAD\_PM & 0x00400000 & failure to measure proper-motion model \\ 819 ID\_OBJ\_EXT & 0x00800000 & extended in Pan-STARRS data \\ 820 ID\_OBJ\_EXT\_ALT & 0x01000000 & extended in external data (2MASS) \\ 821 ID\_OBJ\_GOOD & 0x02000000 & good-quality measurement in Pan-STARRS data \\ 822 ID\_OBJ\_GOOD\_ALT & 0x04000000 & good-quality measurement in external data (2MASS) \\ 823 ID\_OBJ\_GOOD\_STACK & 0x08000000 & good-quality object in the stack ($> 1$ good stack) \\ 824 ID\_OBJ\_BEST\_STACK & 0x10000000 & the primary stack measurements are the ``best'' measurements \\ 825 ID\_OBJ\_SUSPECT\_STACK & 0x20000000 & suspect object in the stack ($> 1$ good or suspect stack, $< 2$ good) \\ 826 ID\_OBJ\_BAD\_STACK & 0x40000000 & poor-quality object in the stack ($< 1$ good stack) \\ 827 \hline 828 \end{tabular} 829 \end{center} 830 \end{table*} 831 832 %% Image.flags => ImageMeta.qaFlags 833 834 \begin{table*} 835 \begin{center} 836 \footnotesize 837 \caption{\label{tab:image_mask_values} Per-Image Flag Bit Values} % \vspace{-0.5cm} 838 \begin{tabular}{lcl} 839 \hline 840 \hline 841 {\bf Bit Name} & {\bf Bit Value} & {\bf Description} \\ 842 \hline 843 ID\_IMAGE\_NEW & 0x00000000 & no calibrations yet attempted \\ 844 ID\_IMAGE\_PHOTOM\_NOCAL & 0x00000001 & user-set value used within relphot: ignore \\ 845 ID\_IMAGE\_PHOTOM\_POOR & 0x00000002 & relphot says image is bad (dMcal > limit) \\ 846 ID\_IMAGE\_PHOTOM\_SKIP & 0x00000004 & user-set value: assert that this image has bad photometry \\ 847 ID\_IMAGE\_PHOTOM\_FEW & 0x00000008 & currently too few measurements for photometry \\ 848 ID\_IMAGE\_ASTROM\_NOCAL & 0x00000010 & user-set value used within relastro: ignore \\ 849 ID\_IMAGE\_ASTROM\_POOR & 0x00000020 & relastro says image is bad (dR,dD > limit) \\ 850 ID\_IMAGE\_ASTROM\_FAIL & 0x00000040 & relastro fit diverged, fit not applied \\ 851 ID\_IMAGE\_ASTROM\_SKIP & 0x00000080 & user-set value: assert that this image has bad astrometry \\ 852 ID\_IMAGE\_ASTROM\_FEW & 0x00000100 & currently too few measurements for astrometry \\ 853 ID\_IMAGE\_PHOTOM\_UBERCAL & 0x00000200 & externally-supplied photometry zero point from ubercal analysis \\ 854 ID\_IMAGE\_ASTROM\_GMM & 0x00000400 & image was fitted to positions corrected by the galaxy motion model \\ 855 \hline 856 \end{tabular} 857 \end{center} 858 \end{table*} 859 665 860 %% \note{need to describe the assignment of flags, etc, for the external data sources}. 666 861 … … 775 970 camera position. Each image which is part of the ubercal subset is 776 971 marked with a bit in the field \code{Image.flags}: 777 \code{ID_IMAGE_PHOTOM_UBERCAL = 0x00000200} 972 \code{ID_IMAGE_PHOTOM_UBERCAL = 0x00000200}. 778 973 779 974 \begin{table}[hb] … … 1284 1479 Table~\ref{tab:secf_mask_values}). 1285 1480 1286 \begin{table*} 1287 \begin{center} 1288 \footnotesize 1289 \caption{\label{tab:secf_mask_values} Relphot Per-Filter Info Flag Bit Values} % \vspace{-0.5cm} 1290 \begin{tabular}{lcl} 1291 \hline 1292 \hline 1293 {\bf Bit Name} & {\bf Bit Value} & {\bf Description} \\ 1294 \hline 1295 ID\_SECF\_STAR\_FEW & 0x00000001 & Used within relphot: skip star \\ 1296 ID\_SECF\_STAR\_POOR & 0x00000002 & Used within relphot: skip star \\ 1297 ID\_SECF\_USE\_SYNTH & 0x00000004 & Synthetic photometry used in average measurement \\ 1298 ID\_SECF\_USE\_UBERCAL & 0x00000008 & Ubercal photometry used in average measurement \\ 1299 ID\_SECF\_HAS\_PS1 & 0x00000010 & PS1 photometry used in average measurement \\ 1300 ID\_SECF\_HAS\_PS1\_STACK & 0x00000020 & PS1 stack photometry exists \\ 1301 ID\_SECF\_HAS\_TYCHO & 0x00000040 & Tycho photometry used for synth mags \\ 1302 ID\_SECF\_FIX\_SYNTH & 0x00000080 & Synth mags repaired with zpt map \\ 1303 ID\_SECF\_RANK\_0 & 0x00000100 & Average magnitude uses rank 0 values \\ 1304 ID\_SECF\_RANK\_1 & 0x00000200 & Average magnitude uses rank 1 values \\ 1305 ID\_SECF\_RANK\_2 & 0x00000400 & Average magnitude uses rank 2 values \\ 1306 ID\_SECF\_RANK\_3 & 0x00000800 & Average magnitude uses rank 3 values \\ 1307 ID\_SECF\_RANK\_4 & 0x00001000 & Average magnitude uses rank 4 values \\ 1308 ID\_SECF\_OBJ\_EXT\_PSPS & 0x00002000 & In PSPS ID\_SECF\_OBJ\_EXT is saved here so it fits within 16 bits \\ 1309 ID\_SECF\_STACK\_PRIMARY & 0x00004000 & PS1 stack photometry includes a primary skycell \\ 1310 ID\_SECF\_STACK\_BESTDET & 0x00008000 & PS1 stack best measurement is a detection (not forced) \\ 1311 ID\_SECF\_STACK\_PRIMDET & 0x00010000 & PS1 stack primary measurement is a detection (not forced) \\ 1312 ID\_SECF\_STACK\_PRIMARY\_MULTIPLE & 0x00020000 & PS1 stack object has multiple primary measurements \\ 1313 ID\_SECF\_HAS\_SDSS & 0x00100000 & This photcode has SDSS photometry \\ 1314 ID\_SECF\_HAS\_HSC & 0x00200000 & This photcode has HSC photometry \\ 1315 ID\_SECF\_HAS\_CFH & 0x00400000 & This photcode has CFH photometry (mostly Megacam) \\ 1316 ID\_SECF\_HAS\_DES & 0x00800000 & This photcode has DES photometry \\ 1317 ID\_SECF\_OBJ\_EXT & 0x01000000 & Extended in this band \\ 1318 \hline 1319 \end{tabular} 1320 \end{center} 1321 \end{table*} 1481 %% where do these go? analyis? 1482 %% ID_GALPHOT_FAIL_FIT = 0x00000001, // fit failed to converge or was degenerate 1483 %% ID_GALPHOT_TOO_FEW = 0x00000002, // not enough points to fit the model 1484 %% ID_GALPHOT_OUT_OF_RANGE = 0x00000004, // fit minimum too far outside data range 1485 %% ID_GALPHOT_BAD_ERROR = 0x00000008, // invalid error (nan or inf) 1322 1486 1323 1487 \subsubsection{Iteratively Reweighted Least Squares Fitting} … … 1433 1597 1434 1598 In addition to the these relatively rare failure cases, the objects 1435 detected in the stacks are more likely to have multiple measurements1599 detected in the stacks may also have multiple measurements 1436 1600 due to the overlap between neighboring stack images. The skycells 1437 1601 (within which the stacks are generated) for a given projection cell 1438 are defined to have significant overlap between neighbors to ensure a1602 are defined to have significant overlap between neighbors to ensure that a 1439 1603 modestly-extended object can be measured completely on the pixels in a 1440 1604 single skycell image. For the \ippmisc{RINGS.V3} skycell tessellation … … 1480 1644 the skycell ``primary'' boundary. Thus, for a given object in the 1481 1645 database, we expect all 5 filters to provide a ``primary'' measurement 1482 from the same skycell for each object. 1646 from the same skycell for each object. Also note that a faint object, 1647 near the detection limit of the stack, may be detected on a 1648 secondary skycell but not (due to statistical flucuations) be detected 1649 on the corresponding primary skycell. Thus it is expected that some 1650 objects may be lacking any primary detections. 1483 1651 1484 1652 Since the ``primary'' identification is purely based on the skycell … … 1587 1755 First, the astrometric calibration has a larger number of systematic 1588 1756 effects which must be performed. These consist of: 1) the 1589 Koppenh\"of fer Effect, 2) Differential Chromatic Refraction, 3) Static1757 Koppenh\"ofer Effect, 2) Differential Chromatic Refraction, 3) Static 1590 1758 deviations in the camera. We discuss each of these in turn below. 1591 1759 1592 \subsubsection{Koppenh\"of fer Effect}1593 1594 The Koppenh\"of fer Effect was first identified in February 2011 by1595 Johannes Koppenh\"of fer (MPE) as part of the effort to search for1760 \subsubsection{Koppenh\"ofer Effect} 1761 1762 The Koppenh\"ofer Effect was first identified in February 2011 by 1763 Johannes Koppenh\"ofer (MPE) as part of the effort to search for 1596 1764 planet transists in the Stellar Transit Survey data. He noticed that 1597 1765 the astromety of bright stars and faint stars disagreed on overlapping … … 1619 1787 % \note{was there is significant difference using a surface brightness version?} 1620 1788 1621 We measured the Koppenh\"of fer Effect by accumulating the residual1789 We measured the Koppenh\"ofer Effect by accumulating the residual 1622 1790 astrometry statistics for stars in the database. For each chip, we 1623 1791 measured the mean X and Y displacements of the astrometric residuals … … 1860 2028 Measure.XoffDCR,YoffDCR, Measure.XoffCAM,YoffCAM}. The offsets are 1861 2029 calculated for each measurement based on the observed instrumental 1862 chip magnitudes and FWHM for the Koppenh offer Effect, on the average2030 chip magnitudes and FWHM for the Koppenh\"ofer Effect, on the average 1863 2031 chip colors and the altitude \& azimuth of each measurement for the 1864 2032 DCR correction, and on the chip coordinates for the astrometric … … 2219 2387 * zero point history, including / excluding ubercal? (from Eddie) 2220 2388 * applied flat-field images [FITS -> png] 2221 * Koppenhof fer plots [from presentations]2389 * Koppenhofer plots [from presentations] 2222 2390 * DCR plots [exist] 2223 2391 * astrometric flat fields [FITS -> png]
Note:
See TracChangeset
for help on using the changeset viewer.
