VWDB Višnjan–Washington Sky Survey
Stand-in data
STAND-IN DATA. This catalog contains 2,279 ZTF detections and 1,000,000 synthetic fixture rows — NOT Visnjan-Washington observations. Stand-in data is loaded while the VW Data Analysis Pipeline is built. Do not use these measurements for science.

Published schema

Generated from schema/schema.yaml — the same file that generates the tables, the TAP_SCHEMA metadata and the search form. These are the only names an ADQL query may use.

survey.source

One row per detection (or forced measurement) per exposure.

columntypeunitUCD description
source_id long meta.id;meta.main Unique detection identifier.
run_id int meta.id Processing run that produced this row; see survey.processing_runs. run_id is where a row came from, and a search returns every run at once. Run 0 is the reserved synthetic fixture; any other run is a real ingest — ZTF stand-in data today (ADR 004), VW observations later. Filter on this column to keep one of them.
exposure_id long meta.id Exposure this measurement was made on.
mjd double d time.epoch Modified Julian Date at exposure mid-point, UTC.
ra double deg pos.eq.ra;meta.main Measured right ascension, ICRS.
dec double deg pos.eq.dec;meta.main Measured declination, ICRS.
flux float nJy phot.flux Calibrated flux.
flux_err float nJy stat.error;phot.flux 1-sigma uncertainty on flux.
snr float stat.snr Signal-to-noise ratio of the measurement.
is_detection boolean meta.code False for forced photometry, which may be an upper limit.
flags long meta.code.qual Quality bitmask; see named boolean columns. flags is a raw bitmask and the meaning of its bits is not defined anywhere in this project — for stand-in rows it is ZTF catflags, passed through unchanged. Compare whole values, or test a bit you already know the meaning of.

survey.exposures

One row per calibrated exposure, with its sky footprint.

columntypeunitUCD description
exposure_id long meta.id;meta.main Unique exposure identifier.
run_id int meta.id Processing run that produced this row; see survey.processing_runs.
band char instr.bandpass Filter, from the controlled vocabulary in ingest/headers.py.
mjd_start double d time.start MJD at the start of the exposure, UTC.
exptime float s time.duration;obs.exposure Exposure time in seconds.
footprint spoly pos.outline;obs.field Sky footprint polygon, ICRS, from the image WCS. footprint is a polygon, not a number: it is queried by position, not by a comparison. It is also NULL for every stand-in ZTF exposure (ADR 004).
seeing_arcsec float arcsec instr.obsty.seeing Delivered image quality, FWHM. seeing_arcsec is NULL for every stand-in ZTF exposure — the IRSA lightcurve service does not publish it (ADR 004). Any comparison against it therefore drops all ZTF detections, silently: NULL is neither less nor greater than anything.
zp float mag phot.calib Photometric zero point.
zp_scatter float mag stat.error;phot.calib Scatter in the zero-point fit; a quality indicator.
airmass float obs.airMass Airmass at observation, secant of the zenith angle. airmass is NULL for any exposure ingested before this column existed (issue #16) — re-run ingest/ztf.py over a region to backfill it.
limitmag float mag phot.mag;obs.param Limiting magnitude reported by the pipeline for this exposure. limitmag is NULL for any exposure ingested before this column existed (issue #16) — re-run ingest/ztf.py over a region to backfill it.

A bare column name that appears in both tables — run_id, exposure_id — has to be qualified in ADQL (source.run_id), because guessing would silently answer a different question.