Table information for 'ztf.detection'

General

Table Description:

Individual detections for each ZTF object including photometric measurements, RealBogus quality scores, corrected magnitudes, and image quality flags.

This table is available for ADQL queries and through the TAP endpoint.

Resource Description:

Legacy ZTF astronomical catalog containing objects, detections, photometric measurements, classifications, and cross-matches from the Zwicky Transient Facility (ZTF) survey, as processed by the ALeRCE broker pipeline.

For a list of all services and tables belonging to this table's resource, see Information on resource 'ALeRCE ZTF Legacy Catalog'

Citing this table

To cite the table as such, we suggest the following BibTeX entry:

@MISC{vo:ztf_detection,
  year=2026,
  title={{ZTF} Detection table},
  author={{ALeRCE} Team},
  url={http://tap.alerce.online/tableinfo/ztf.detection},
  howpublished={{VO} resource provided by the {ALeRCE} {TAP} service}
}

Columns

Sorted by DB column index. [Sort alphabetically]

NameTable Head DescriptionUnitUCD
candid Candid Candidate identifier from ZTF alert stream N/A meta.id
oid Oid Object identifier N/A meta.id;src
mjd Mjd Modified Julian Date of observation d time.epoch
fid Fid Filter identifier (1=g, 2=r, 3=i) N/A meta.id;instr.filter
pid Pid Processing identifier N/A meta.id
diffmaglim Diffmaglim 5-sigma limiting magnitude in difference image mag phot.mag;stat.max
isdiffpos Isdiffpos Sign of flux in difference image (1=positive, -1=negative) N/A meta.code
nid Nid Night identifier N/A meta.id
ra Ra Right ascension of candidate (ICRS) deg pos.eq.ra;meta.main
dec Dec Declination of candidate (ICRS) deg pos.eq.dec;meta.main
magpsf Magpsf Magnitude from PSF-fit photometry mag phot.mag
sigmapsf Sigmapsf 1-sigma uncertainty in PSF-fit magnitude mag stat.error;phot.mag
magap Magap Aperture magnitude (small aperture, ~2 arcsec radius) mag phot.mag
sigmagap Sigmagap 1-sigma uncertainty in small aperture magnitude mag stat.error;phot.mag
distnr Distnr Distance to nearest source in reference image arcsec pos.angDistance
rb Rb RealBogus quality score (0=bogus, 1=real) N/A stat.probability;src.class
rbversion Rbversion RealBogus classifier version N/A meta.version
drb Drb Deep learning RealBogus quality score N/A stat.probability;src.class
drbversion Drbversion Deep RealBogus classifier version N/A meta.version
magapbig Magapbig Aperture magnitude (large aperture, ~5 arcsec radius) mag phot.mag
sigmagapbig Sigmagapbig 1-sigma uncertainty in large aperture magnitude mag stat.error;phot.mag
rfid Rfid Reference image field identifier N/A meta.id
magpsf_corr Magpsf_corr Corrected PSF-fit magnitude (host-galaxy subtracted) mag phot.mag
sigmapsf_corr Sigmapsf_corr 1-sigma uncertainty in corrected PSF magnitude mag stat.error;phot.mag
sigmapsf_corr_ext Sigmapsf_corr_ext Extended uncertainty including systematics in corrected PSF magnitude mag stat.error;phot.mag
corrected Corrected Whether photometric correction was applied to this detection N/A meta.code.qual
dubious Dubious Flag indicating a potentially unreliable detection N/A meta.code.qual
parent_candid Parent_candid Candidate identifier of the parent detection N/A meta.id;meta.parent
has_stamp Has_stamp Whether a postage stamp image is available for this detection N/A meta.code
step_id_corr Step_id_corr Step identifier for the photometric correction pipeline N/A meta.id

Columns that are parts of indices are marked like this.

VOResource

VO nerds may sometimes need VOResource XML for this table.