Coordinates (20 columns)
- RA (D) [deg] SAS task
catcorr
-
Corrected Right Ascension of the detection in degrees (J2000) after
statistical correlation of the emldetect coordinates, RA_UNC and DEC_UNC, with the USNO B1.0, 2MASS or SDSS
(DR8) optical/IR source catalogues using the SAS task catcorr
(the process of correcting the coordinates is also referred to as field
rectification). In cases where
the cross-correlation is determined to be unreliable, no correction is
applied and this value is therefore the same as RA_UNC (cf. Sec. 3XMM-DR4 UG, Sec. 3.4).
-
DEC (D) [deg]SAS task
catcorr
-
Corrected Declination of the detection in degrees (J2000) after
statistical correlation of the emldetect coordinates, RA_UNC and DEC_UNC, with the USNO B1.0, 2MASS or SDSS
(DR8) optical/IR source catalogues using the SAS task catcorr
(the process of correcting the coordinates is also referred to as field
rectification). In cases where
the cross-correlation is determined to be unreliable no correction is
applied and this value is therefore the same as DEC_UNC (cf. Sec. 3XMM-DR4 UG, Sec. 3.4).
-
POSERR (E) [arcsec]
-
Total radial position uncertainty in arcseconds calculated by
combining the statistical error RADEC_ERR and the error arising from the field rectification process SYSERRCC
as follows: POSERR = SQRT ( RADEC_ERR^2 + SYSERRCC^2 ). For a
2-dimensional Gaussian error distribution, this radius reflects a 63%
probability that the true source position lies within this radius of the
measured position. The corresponding 68% confidence radius is
1.0714*RADEC_ERR.
-
LII (D) [deg]SAS task
catcorr
-
Galactic longitude of the detection in degrees corresponding to the
(corrected) coordinates RA and
DEC.
-
BII (D) [deg]SAS task
catcorr
-
Galactic latitude of the detection in degrees corresponding to the
(corrected) coordinates RA and
DEC.
-
RADEC_ERR (E) [arcsec]SAS task emldetect
-
RADEC_ERR (E) [arcsec] is a radial error on the position, computed as sqrt( ra_err2 + dec_err2),
in arcsecs, where ra_err and dec_err are the 1 σ uncertainties in the
RA and DEC coordinates respectively. The ra_err and dec_err quantities
are provided, in image pixel units, in the X_IMA_ERR and Y_IMA_ERR
columns, respectively, in the P*OMSRLI*.FIT pipeline product file of
each observation - they are not provided directly in the catalogue.
-
SYSERRCC (E) [arcsec]SAS tasks catcorr
-
The estimated error arising from the field rectification
process (in arcseconds). If the SAS task catcorr results in a
statistically reliable cross-correlation with the USNO B1.0, 2MASS or
SDSS (DR8) optical/IR catalogues, SYSERRCC combines the 1 σ errors on the
translational shifts in the RA (rashift_error) and DEC (decshift_error)
directions, together with the rotational error component, derived from
from the catalogue that yields the 'best' solution, as follows:
SYSERRCC = SQRT ( rashift_error2 + decshift_error2 + (r * thetarot_error)2 )
where r is the radial off-axis angle of the detection from the spacecraft
boresight in arcsecs and thetarot_error is the 1 σ error on the rotational
correction (in radians). Where catcorr fails to obtain a
statistically reliable result,
SYSERRCC is 1.5 arcseconds (see Sec. 3XMM-DR4 UG, Sec.
3.4 for details). Note that rashift_error, decshift_error and
thetarot_error are not provided separately in the catalogue.
-
REFCAT (I) SAS task catcorr
-
An integer code reflecting the absolute astrometric reference catalogue
which gave the statistically 'best' result for the field rectification
process (from which the corrections are taken). It is 1 for the
SDSS (DR9) catalogue, 2 for 2MASS and 3 for USNO B1.0. Where
catcorr fails to produce a reliable solution, REFCAT is a
negative number, indicating the cause of the failure.
The failure codes are -1 = Too few matches (< 10), -2 = poor fit
(goodness of fit parameter in catcorr < 5.0), -3 = error on
the field positional rectification correction is > 0.75 arcseconds)
(see Sec. 3XMM-DR4 UG, Sec. 3.4). This column is new in 3XMM-DR4..
-
POSCOROK (B) SAS task catcorr
-
Signifies whether catcorr obtained a statistically reliable
solution or not. This parameter is redundant in the sense that if
REFCAT is positive, then a
reliable solution was considered to have been found (see Sec. 3XMM-DR4 UG, Sec. 3.4). This column is new in 3XMM-DR4..
-
RA_UNC (D) [deg]SAS
task emldetect
-
Right Ascension of the detection in degrees (J2000) as determined by
the SAS task emldetect by fitting a detection
simultaneously in all cameras and energy bands.
-
DEC_UNC (D) [deg]SAS
task emldetect
-
Declination of the detection in degrees (J2000) as determined by the
SAS task emldetect by fitting a detection simultaneously in
all cameras and energy bands.
-
CCDPN (J)SAS
task emldetect
- pn CCD number on which the detection was made. This column is new in 3XMM-DR6.
-
PN_RAWX (J)SAS
task emldetect
- Raw pixel position in the X direction of the pn detection. This column is new in 3XMM-DR6.
-
PN_RAWY (J)SAS
task emldetect
- Raw pixel position in the Y direction of the pn detection. This column is new in 3XMM-DR6.
-
CCDM1 (J)SAS
task emldetect
- MOS1 CCD number on which the detection was made. This column is new in 3XMM-DR6.
-
M1_RAWX (J)SAS
task emldetect
- Raw pixel position in the X direction of the MOS1 detection. This column is new in 3XMM-DR6.
-
M1_RAWY (J)SAS
task emldetect
- Raw pixel position in the X direction of the MOS1 detection. This column is new in 3XMM-DR6.
-
CCDM2 (J)SAS
task emldetect
- MOS2 CCD number on which the detection was made. This column is new in 3XMM-DR6.
-
M2_RAWX (J)SAS
task emldetect
- Raw pixel position in the X direction of the MOS2 detection. This column is new in 3XMM-DR6.
-
M2_RAWY (J)SAS
task emldetect
- Raw pixel position in the X direction of the MOS2 detection. This column is new in 3XMM-DR6.