Table information for 'ztf.forced_photometry'

General

Table Description:

Forced photometry measurements obtained at object positions for all ZTF epochs, including flux measurements, photometric calibration parameters, and image quality metrics.

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_forced_photo,
  year=2026,
  title={{ZTF} Forced Photometry},
  author={{ALeRCE} Team},
  url={http://tap.alerce.online/tableinfo/ztf.forced_photometry},
  howpublished={{VO} resource provided by the {ALeRCE} {TAP} service}
}

Columns

Sorted by DB column index. [Sort alphabetically]

NameTable Head DescriptionUnitUCD
pid Pid Processing identifier 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
ra Ra Right ascension (ICRS) deg pos.eq.ra;meta.main
dec Dec Declination (ICRS) deg pos.eq.dec;meta.main
e_ra E_ra Uncertainty in right ascension deg stat.error;pos.eq.ra
e_dec E_dec Uncertainty in declination deg stat.error;pos.eq.dec
mag Mag Magnitude from forced photometry mag phot.mag
e_mag E_mag Uncertainty in forced photometry magnitude mag stat.error;phot.mag
mag_corr Mag_corr Corrected forced photometry magnitude mag phot.mag
e_mag_corr E_mag_corr Uncertainty in corrected forced photometry magnitude mag stat.error;phot.mag
e_mag_corr_ext E_mag_corr_ext Extended uncertainty including systematics in corrected forced photometry magnitude mag stat.error;phot.mag
isdiffpos Isdiffpos Sign of flux in difference image (1=positive, -1=negative) N/A meta.code
corrected Corrected Whether photometric correction was applied N/A meta.code.qual
dubious Dubious Flag indicating a potentially unreliable measurement N/A meta.code.qual
parent_candid Parent_candid Parent candidate identifier N/A meta.id;meta.parent
has_stamp Has_stamp Whether a postage stamp image is available N/A meta.code
field Field ZTF field identifier N/A obs.field
rcid Rcid Readout channel identifier N/A meta.id;instr.det
rfid Rfid Reference image field identifier N/A meta.id
sciinpseeing Sciinpseeing Seeing FWHM of science image arcsec instr.obsty.seeing
scibckgnd Scibckgnd Background level in science image N/A instr.background
scisigpix Scisigpix Pixel-level noise (sigma) in science image N/A stat.error;instr.background
magzpsci Magzpsci Photometric zero-point magnitude for science image mag phot.calib
magzpsciunc Magzpsciunc Uncertainty in photometric zero-point magnitude mag stat.error;phot.calib
magzpscirms Magzpscirms RMS of zero-point magnitude fit mag stat.rms;phot.calib
clrcoeff Clrcoeff Color coefficient for photometric calibration N/A phot.color;arith.ratio
clrcounc Clrcounc Uncertainty in color coefficient N/A stat.error;phot.color;arith.ratio
exptime Exptime Exposure time s time.duration;obs.exposure
adpctdif1 Adpctdif1 Adaptive percent difference in astrometric solution (axis 1) N/A stat.fit.residual
adpctdif2 Adpctdif2 Adaptive percent difference in astrometric solution (axis 2) N/A stat.fit.residual
diffmaglim Diffmaglim 5-sigma limiting magnitude in difference image mag phot.mag;stat.max
programid Programid ZTF program identifier N/A meta.id;obs
procstatus Procstatus Processing status code N/A meta.code.status
distnr Distnr Distance to nearest source in reference image arcsec pos.angDistance
ranr Ranr Right ascension of nearest source in reference image deg pos.eq.ra
decnr Decnr Declination of nearest source in reference image deg pos.eq.dec
magnr Magnr Magnitude of nearest source in reference image mag phot.mag
sigmagnr Sigmagnr Uncertainty in magnitude of nearest source in reference image mag stat.error;phot.mag
chinr Chinr Chi value of nearest source match in reference image N/A stat.fit.chi2
sharpnr Sharpnr Sharpness of nearest source in reference image N/A src.morph.param

Columns that are parts of indices are marked like this.

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