14.4.4 panstarrs1_original_valid

The Panoramic Survey Telescope and Rapid Response System (Pan-STARRS) is a system for wide-field astronomical imaging developed and operated by the Institute for Astronomy at the University of Hawaii. Pan-STARRS1 (PS1) is the first part of Pan-STARRS to be completed and is the basis for Data Release 1 (DR1). The PS1 survey used a 1.8 meter telescope and its 1.4 Gigapixel camera to image the sky in five broadband filters (g, r, i, z, y).
The current table contains a filtered subsample of the 10 723 304 629 entries listed in the original ObjectThin table.
We used only ObjectThin and MeanObject tables to extract panstarrs1OriginalValid table, this means that objects detected only in stack images are not included here. The main reason for us to avoid the use of objects detected in stack images is that their astrometry is not as good as the mean objects astrometry: ”The stack positions (raStack, decStack) have considerably larger systematic astrometric errors than the mean epoch positions (raMean, decMean).” The astrometry for the MeanObject positions uses Gaia DR1 as a reference catalog, while the stack positions use 2MASS as a reference catalog.
In details, we filtered out all objects where:

  • n_detections = 1

  • no good quality data in Pan-STARRS, obj_info_flag 33554432 not set

  • mean astrometry could not be measured, obj_info_flag 524288 set

  • stack position used for mean astrometry, obj_info_flag 1048576 set

  • error on all magnitudes equal to 0 or to -999;

  • all magnitudes set to -999;

  • error on RA or DEC greater than 1 arcsec.

The number of objects in panstarrs1OriginalValid is 2 264 263 282.

The panstarrs1OriginalValid table contains only a subset of the columns available in the combined ObjectThin and MeanObject tables. A description of the original ObjectThin and MeanObjects tables can be found at: https://outerspace.stsci.edu/display/PANSTARRS/PS1+Database+object+and+detection+tables
Download:
http://mastweb.stsci.edu/ps1casjobs/home.aspx
Documentation:
https://outerspace.stsci.edu/display/PANSTARRS
http://pswww.ifa.hawaii.edu/pswww/
References:
The Pan-STARRS1 Surveys, Chambers, K.C., et al. 2016, arXiv:1612.05560
Pan-STARRS Data Processing System, Magnier, E. A., et al. 2016, arXiv:1612.05240
Pan-STARRS Pixel Processing: Detrending, Warping, Stacking, Waters, C. Z., et al. 2016, arXiv:1612.05245
Pan-STARRS Pixel Analysis: Source Detection and Characterization, Magnier, E. A., et al. 2016, arXiv:1612.05244
Pan-STARRS Photometric and Astrometric Calibration, Magnier, E. A., et al. 2016, arXiv:1612.05242
The Pan-STARRS1 Database and Data Products, Flewelling, H. A., et al. 2016, arXiv:1612.05243

Columns description:

obj_name : IAU name (string)

IAU name for this object (from original table ObjectThin).

obj_id : Unique Object Identifier (long)

Unique object identifier (from original tables ObjectThin and MeanObject).

ra : RA Mean (float, Angle[deg])

Right Ascention from single epoch detections (weighted mean) in Equinox J2000.0 at the mean epoch given by epoch_mean and calibrated against Gaia DR1 (from original table ObjectThin).

dec : DEC Mean (float, Angle[deg])

Declination from single epoch detections (weighted mean) in Equinox J2000.0 at the mean epoch given by epoch_mean and calibrated against Gaia DR1 (from original table ObjectThin).

ra_error : RA Mean standard deviation (double, Angle[arcsec])

Right Ascension standard deviation from single epoch detections (from original table ObjectThin).

dec_error : DEC Mean standard deviation (double, Angle[arcsec])

Declination standard deviation from single epoch detections (from original table ObjectThin).

epoch_mean : Epoch Mean (float, Time[day])

Modified Julian Date of the mean epoch corresponding to raMean, decMean (equinox J2000). From original table ObjectThin.

g_mean_psf_mag : Mean magnitude in g filter (double)

Mean PSF magnitude (AB magnitude) from g filter detections (from original table MeanObject).

g_mean_psf_mag_error : Error in Mean magnitude in g filter (double, Magnitude[mag])

Error in mean PSF magnitude (AB magnitude) from g filter detections (from original table MeanObject).

g_flags : g filter flags (int, Magnitude[mag])

Information flag bitmask for mean object from g filter detections (from original table MeanObject).
Flag values and descriptions are:

  • 1 = Used within relphot (FEW): skip star.

  • 2 = Used within relphot (POOR): skip star.

  • 4 = Synthetic photometry used in average measurement.

  • 8 = Ubercal photometry used in average measurement.

  • 16 = PS1 photometry used in average measurement.

  • 32 = PS1 stack photometry exists.

  • 64 = Tycho photometry used for synthetic magnitudes.

  • 128 = Synthetic magnitudes repaired with zeropoint map.

  • 256 = Average magnitude calculated in 0th pass.

  • 512 = Average magnitude calculated in 1th pass.

  • 1024 = Average magnitude calculated in 2th pass.

  • 2048 = Average magnitude calculated in 3th pass.

  • 4096 = Average magnitude calculated in 4th pass.

  • 8192 = Extended in this band (PSPS only).

  • 16384 = PS1 stack photometry comes from primary skycell.

r_mean_psf_mag : Mean magnitude in r filter (double, Magnitude[mag])

Mean PSF magnitude (AB magnitude) from r filter detections (from original table MeanObject).

r_mean_psf_mag_error : Error in Mean magnitude in r filter (double, Magnitude[mag])

Error in mean PSF magnitude (AB magnitude) from r filter detections (from original table MeanObject).

r_flags : r filter flags (int)

Information flag bitmask for mean object from r filter detections (from original table MeanObject).
Flag values and descriptions are:

  • 1 = Used within relphot (FEW): skip star.

  • 2 = Used within relphot (POOR): skip star.

  • 4 = Synthetic photometry used in average measurement.

  • 8 = Ubercal photometry used in average measurement.

  • 16 = PS1 photometry used in average measurement.

  • 32 = PS1 stack photometry exists.

  • 64 = Tycho photometry used for synthetic magnitudes.

  • 128 = Synthetic magnitudes repaired with zeropoint map.

  • 256 = Average magnitude calculated in 0th pass.

  • 512 = Average magnitude calculated in 1th pass.

  • 1024 = Average magnitude calculated in 2th pass.

  • 2048 = Average magnitude calculated in 3th pass.

  • 4096 = Average magnitude calculated in 4th pass.

  • 8192 = Extended in this band (PSPS only).

  • 16384 = PS1 stack photometry comes from primary skycell.

i_mean_psf_mag : Mean magnitude in i filter (double, Magnitude[mag])

Mean PSF magnitude (AB magnitude) from i filter detections (from original table MeanObject).

i_mean_psf_mag_error : Error in Mean magnitude in i filter (double, Magnitude[mag])

Error in mean PSF magnitude (AB magnitude) from i filter detections (from original table MeanObject).

i_flags : i filter flags (int)

Information flag bitmask for mean object from i filter detections (from original table MeanObject).
Flag values and descriptions are:

  • 1 = Used within relphot (FEW): skip star.

  • 2 = Used within relphot (POOR): skip star.

  • 4 = Synthetic photometry used in average measurement.

  • 8 = Ubercal photometry used in average measurement.

  • 16 = PS1 photometry used in average measurement.

  • 32 = PS1 stack photometry exists.

  • 64 = Tycho photometry used for synthetic magnitudes.

  • 128 = Synthetic magnitudes repaired with zeropoint map.

  • 256 = Average magnitude calculated in 0th pass.

  • 512 = Average magnitude calculated in 1th pass.

  • 1024 = Average magnitude calculated in 2th pass.

  • 2048 = Average magnitude calculated in 3th pass.

  • 4096 = Average magnitude calculated in 4th pass.

  • 8192 = Extended in this band (PSPS only).

  • 16384 = PS1 stack photometry comes from primary skycell.

z_mean_psf_mag : Mean magnitude in z filter (double, Magnitude[mag])

Mean PSF magnitude (AB magnitude) from z filter detections (from original table MeanObject).

z_mean_psf_mag_error : Error in Mean magnitude in z filter (double, Magnitude[mag])

Error in mean PSF magnitude (AB magnitude) from z filter detections (from original table MeanObject).

z_flags : z filter flags (int)

Information flag bitmask for mean object from z filter detections (from original table MeanObject).
Flag values and descriptions are:

  • 1 = Used within relphot (FEW): skip star.

  • 2 = Used within relphot (POOR): skip star.

  • 4 = Synthetic photometry used in average measurement.

  • 8 = Ubercal photometry used in average measurement.

  • 16 = PS1 photometry used in average measurement.

  • 32 = PS1 stack photometry exists.

  • 64 = Tycho photometry used for synthetic magnitudes.

  • 128 = Synthetic magnitudes repaired with zeropoint map.

  • 256 = Average magnitude calculated in 0th pass.

  • 512 = Average magnitude calculated in 1th pass.

  • 1024 = Average magnitude calculated in 2th pass.

  • 2048 = Average magnitude calculated in 3th pass.

  • 4096 = Average magnitude calculated in 4th pass.

  • 8192 = Extended in this band (PSPS only).

  • 16384 = PS1 stack photometry comes from primary skycell.

y_mean_psf_mag : Mean magnitude in y filter (double, Magnitude[mag])

Mean PSF magnitude (AB magnitude) from y filter detections (from original table MeanObject).

y_mean_psf_mag_error : Error in Mean magnitude in y filter (double, Magnitude[mag])

Error in mean PSF magnitude (AB magnitude) from y filter detections (from original table MeanObject).

y_flags : y filter flags (int)

Information flag bitmask for mean object from z filter detections (from original table MeanObject).
Flag values and descriptions are:

  • 1 = Used within relphot (FEW): skip star.

  • 2 = Used within relphot (POOR): skip star.

  • 4 = Synthetic photometry used in average measurement.

  • 8 = Ubercal photometry used in average measurement.

  • 16 = PS1 photometry used in average measurement.

  • 32 = PS1 stack photometry exists.

  • 64 = Tycho photometry used for synthetic magnitudes.

  • 128 = Synthetic magnitudes repaired with zeropoint map.

  • 256 = Average magnitude calculated in 0th pass.

  • 512 = Average magnitude calculated in 1th pass.

  • 1024 = Average magnitude calculated in 2th pass.

  • 2048 = Average magnitude calculated in 3th pass.

  • 4096 = Average magnitude calculated in 4th pass.

  • 8192 = Extended in this band (PSPS only).

  • 16384 = PS1 stack photometry comes from primary skycell.

n_detections : Number of detections (short)

Number of single epoch detections summed over all filters (from original table ObjectThin).

zone_id : Local zone index (int)

Local zone index, found by dividing the sky into bands of declination 1/2 arcminute in height: zoneID = floor((90 + declination)/0.0083333). From original table ObjectThin.

obj_info_flag : Object information flags (int)

Information flag bitmask indicating details of the photometry (from original table ObjectThin).
Flag values and descriptions are:

  • 0 = Initial value; resets all bits.

  • 1 = Used within relphot (FEW); skip star.

  • 2 = Used within relphot (POOR); skip star.

  • 4 = object IDed with known ICRF quasar (may have ICRF position measurement).

  • 8 = identified as likely QSO (Hernitschek et al 2015), PQSO0.60.

  • 16 = identified as possible QSO (Hernitschek et al 2015), PQSO0.05.

  • 32 = identified as likely RR Lyra (Hernitschek et al 2015), PRRLyra0.60.

  • 64 = identified as possible RR Lyra (Hernitschek et al 2015), PRRLyra0.05.

  • 128 = identified as a variable based on ChiSq (Hernitschek et al 2015).

  • 256 = identified as a non-periodic (stationary) transient.

  • 512 = at least one detection identified with a known solar-system object (asteroid or other).

  • 1024 = most detections identified with a known solar-system object (asteroid or other).

  • 2048 = star with large proper motion.

  • 4096 = simple weighted average position was used (no IRLS fitting).

  • 8192 = average position was fitted.

  • 16384 = proper motion model was fitted.

  • 32768 = parallax model was fitted.

  • 65536 = average position used (not PM or PAR).

  • 131072 = proper motion used (not AVE or PAR).

  • 262144 = parallax used (not AVE or PM).

  • 524288 = mean astrometry could not be measured.

  • 1048576 = stack position used for mean astrometry.

  • 2097152 = mean astrometry used for stack position.

  • 4194304 = failure to measure proper-motion model.

  • 8388608 = extended in our data (eg, PS).

  • 16777216 = extended in external data (eg, 2MASS).

  • 33554432 = good-quality measurement in our data (eg,PS).

  • 67108864 = good-quality measurement in external data (eg, 2MASS).

  • 134217728 = good-quality object in the stack (>1 good stack measurement).

  • 268435456 = the primary stack measurements are the best measurements.

  • 536870912 = suspect object in the stack (no more than 1 good measurement, 2 or more suspect or good stack measurement).

  • 1073741824 = poor-quality stack object (no more than 1 good or suspect measurement).

quality_flag : Object quality flags (short)

Subset of obj_info_flag denoting whether this object is real or a likely false positive (from original table ObjectThin).
Flag values and descriptions are:

  • 0 = Initial value; resets all bits.

  • 1 = Extended in our data (eg, PS).

  • 2 = Extended in external data (eg, 2MASS).

  • 4 = Good-quality measurement in our data (eg,PS).

  • 8 = Good-quality measurement in external data (eg, 2MASS).

  • 16 = good-quality object in the stack (> 1 good stack measurement).

  • 32 = the primary stack measurements are the best measurements.

  • 64 = suspect object in the stack (no more than 1 good measurement, 2 or more suspect or good stack measurement).

  • 128 = poor-quality stack object (no more than 1 good or suspect measurement).