Information on Service 'AllWISE Data Release'

For a list of all services and tables belonging to this service's resource, see Information on resource 'AllWISE'

Service Documentation

This resource contains the AllWISE Data Release catalogue ( Cutri et al., 2003) that was downloaded from Vizier and limited to HELP coverage. Its full documentation is available there: http://cdsarc.u-strasbg.fr/viz-bin/Cat?II/328

A field column was added containing the name of HELP field associated with each source to allow easy filtering. Here is the number of sources per field:

Field	Count
AKARI-NEP	184904
AKARI-SEP	171262
Bootes	193391
CDFS-SWIRE	226243
COSMOS	71599
EGS	61022
ELAIS-N1	267600
ELAIS-N2	150687
ELAIS-S1	131674
GAMA-09	947803
GAMA-12	837136
GAMA-15	988404
HDF-N	11179
Herschel-Stripe-82	4851288
Lockman-SWIRE	340512
NGP	2648932
SA13	3707
SGP	4321775
SPIRE-NEP	11939
SSDF	1752467
XMM-13hr	12299
XMM-LSS	321009
xFLS	135507

If you need to identify a source, when crossmatching for instance, please use the AllWISE identifier.

Overview

You can access this service using:

• static -- static (i.e. prepared) data or custom client-side code; probably used to access ancillary files here
• form -- allows access via an HTML form
• scs.xml -- a standard SCS interface as defined by the IVOA to access catalog-type data; SCS clients use https://herschel-vos.phys.sussex.ac.uk/allwise/q/cone/scs.xml? to access the service

VOResource XML (that's something exclusively for VO nerds)

Note 1

The parameters of the error ellipse are computed from the 1-σ in RA and Dec (sigra, sigdec) and the co-σ sigradec with the formulae:

Δ	= (sigra2-sigdec2)2 + 4*sigradec2
eeMaj2	= 0.5*(sigra2+sigdec2+sqrt(Δ))
eeMin2	= 0.5*(sigra2+sigdec2-sqrt(Δ))
tan(eePA)	= (eeMaj2-sigdec2)/(sigradec*|sigradec|) = (sigradec*|sigradec|)/(eeMaj2-sigra2)

Conversely, the sigra/sigdec are given by:

sigra2	= eeMaj2sin2(eePA) + eeMin2cos2(eePA)
sigdec2	= eeMaj2cos2(eePA) + eeMin2sin2(eePA)

Note 2

One character per band (W1/W2/W3/W4) that indicates that the photometry and/or position measurements of a source may be contaminated or biased due to proximity to an image artifact:

D,d	Diffraction spike. Source may be a spurious detection of or contaminated by a diffraction spike from a nearby bright star on the same image
P,p	Persistence. Source may be a spurious detection of or contaminated by a latent image left by a bright star
H,h	Halo. Source photometry may be a spurious detection of or contaminated by the scattered light halo surrounding a nearby bright source
O,o	(letter "o") Optical ghost. Source may be a spurious detection of or contaminated by an optical ghost image caused by a nearby bright source
0	(number zero) Source is unaffected by known artifacts.

Note 3

Extended source flag:

0	The source shape is consistent with a point-source and the source is not associated with or superimposed on a 2MASS XSC source.
1	The profile-fit photometry goodness-of-fit, w?rchi2, is >3.0 in one or more bands.
2	The source falls within the extrapolated isophotal footprint of a 2MASS XSC source.
3	The profile-fit photometry goodness-of-fit, w?rchi2, is >3.0 in one or more bands, and The source falls within the extrapolated isophotal footprint of a 2MASS XSC source.
4	The source position falls within 5" of a 2MASS XSC source.
5+	The profile-fit photometry goodness-of-fit, w?rchi2, is >3.0 in one or more bands, and the source position falls within 5" of a 2MASS XSC source.

Note 4

The variability flag is a 4-character string, one character per band, containing a value related to the probability that the source flux measured on the individual WISE exposures is variable.

n	indicates insufficient or inadequate data to make a determination (<6 exposures)
0-9	indicate increasing probabilities of variation:
0-5	are most likely not variable
6-7	are likely variables (but susceptible of false-positive variability)
>7	have the highest probability of being true variables

Note 5

Integer frame detection count. This column gives the number of individual 7.7s exposures on which this source was detected with SNR>3 in the W1 profile-fit measurement. This number can be zero for sources that are well-detected on the coadded Atlas Image, but too faint for detection on the single exposures.

Note 6

Number of individual 7.7s W1 exposures on which a profile-fit measurement of this source was possible. This number can differ between the four bands because band-dependent criteria are used to select individual frames for inclusion in the coadded Atlas Images. This column is null if there is no frame coverage in this band at the position of this source.

Note 7

Five character string that encodes information about factors that impact the accuracy of the motion estimation. These include the original blend count, whether a blend-swap took place, and the distance in hundredths of an arcsecond between the non-motion position and the motion mean-observation-epoch position. The format is NQDDD where N is the original blend count, Q is either "Y" or "N" for "yes" or "no" a blend-swap occurred (i.e., the original primary component was not the final primary component), and DDD is the radial distance between the non-motion and motion at mean-observation epoch positions in units of 0.01 arcsec, clipped at 999 (almost 10 arcsec).

Note 8

Four character flag, one character per band [W1/W2/W3/W4], that provides a shorthand summary of the quality of the profile-fit photometry measurement in each band, as derived from the measurement signal-to-noise ratio:

A	Source is detected in this band with a flux signal-to-noise ratio w?snr>10.
B	Source is detected in this band with a flux signal-to-noise ratio 3<w?snr<10.
C	Source is detected in this band with a flux signal-to-noise ratio 2<w?snr<3.
U	Upper limit on magnitude. Source measurement has w?snr<2. The profile-fit magnitude w?mpro is a 95% confidence upper limit.
X	A profile-fit measurement was not possible at this location in this band. The value of w?mpro and w?sigmpro will be "null" in this band.
Z	A profile-fit source flux measurement was made at this location, but the flux uncertainty could not be measured. The value of w?sigmpro will be "null" in this band. The value of w?mpro will be "null" if the measured flux, w?flux, is negative, but will not be "null" if the flux is positive. If a non-null magnitude is present, it corresponds to the true flux, and not the 95% confidence upper limit. This occurs for a small number of sources found in a narrow range of ecliptic longitude which were covered by a large number of saturated pixels from 3-Band Cryo single-exposures.