Unique source parameters (35 columns)

SC_RA (D) [deg]
The mean Right Ascension in degrees (J2000) of all the detections of the source SRCID (see RA) weighted by the positional errors POSERR.
SC_DEC (D) [deg]
The mean Declination in degrees (J2000) of all the detections of the source SRCID (see DEC) weighted by the positional errors POSERR.
SC_POSERR (E) [arcsec]
The error of the weighted mean position given in SC_RA and SC_DEC in arseconds (see 2XMM UG, Sec. 3.2.4 for details).
SC_EP_1_FLUX (E) [erg/cm2/s]
The mean band 1 flux (0.2 - 0.5 keV) of all the detections of the source SRCID (see EP_1_FLUX) weighted by the errors (EP_1_FLUX_ERR), in erg/cm2/s.]
SC_EP_1_FLUX_ERR (E) [erg/cm2/s]
Error on the weighted mean band 1 flux in SC_EP_1_FLUX (see 2XMM UG, Sec. 3.2.4 for details).
SC_EP_2_FLUX (E) [erg/cm2/s]
The mean band 2 flux (0.5 - 1.0 keV) of all the detections of the source SRCID (see EP_2_FLUX) weighted by the errors (EP_2_FLUX_ERR), in erg/cm2/s.
SC_EP_2_FLUX_ERR (E) [erg/cm2/s]
Error on the weighted mean band 2 flux in SC_EP_2_FLUX (see 2XMM UG, Sec. 3.2.4 for details).
SC_EP_3_FLUX (E) [erg/cm2/s]
The mean band 3 flux (1.0 - 2.0 keV) of all the detections of the source SRCID (see EP_3_FLUX) weighted by the errors (EP_3_FLUX_ERR), in erg/cm2/s.
SC_EP_3_FLUX_ERR (E) [erg/cm2/s]
Error on the weighted mean band 3 flux in SC_EP_3_FLUX (see 2XMM UG, Sec. 3.2.4 for details).
SC_EP_4_FLUX (E) [erg/cm2/s]
The mean band 4 flux (2.0 - 4.5 keV) of all the detections of the source SRCID (see EP_4_FLUX) weighted by the errors (EP_4_FLUX_ERR), in erg/cm2/s.
SC_EP_4_FLUX_ERR (E) [erg/cm2/s]
Error on the weighted mean band 4 flux in SC_EP_4_FLUX (see 2XMM UG, Sec. 3.2.4 for details).
SC_EP_5_FLUX (E) [erg/cm2/s]
The mean band 5 flux (4.5 - 12 keV) of all the detections of the source SRCID (see EP_5_FLUX) weighted by the errors (EP_5_FLUX_ERR), in erg/cm2/s.
SC_EP_5_FLUX_ERR (E) [erg/cm2/s]
Error on the weighted mean band 5 flux in SC_EP_5_FLUX (see 2XMM UG, Sec. 3.2.4 for details).
SC_EP_8_FLUX (E) [erg/cm2/s]
The mean total band flux (0.2 - 12 keV) of all the detections of the source SRCID (see EP_8_FLUX) weighted by the errors (EP_8_FLUX_ERR), in erg/cm2/s.
SC_EP_8_FLUX_ERR (E) [erg/cm2/s]
Error on the weighted mean total band flux in SC_EP_8_FLUX (see 2XMM UG, Sec. 3.2.4 for details).
SC_EP_9_FLUX (E) [erg/cm2/s]
The mean band 9 flux (0.5 - 4.5 keV) of all the detections of the source SRCID (see EP_9_FLUX) weighted by the errors (EP_9_FLUX_ERR), in erg/cm2/s.
SC_EP_9_FLUX_ERR (E) [erg/cm2/s]
Error on the weighted mean band 9 flux in SC_EP_9_FLUX (see 2XMM UG, Sec. 3.2.4 for details).
SC_HR1 (E)
The mean hardness ratio of the bands 1 and 2 of all the detections of the source SRCID (EP_HR1) weighted by the errors(EP_HR1_ERR).
SC_HR1_ERR (E)
Error on the weighted mean hardness ratio in SC_HR1 (see 2XMM UG, Sec. 3.2.4 for details).
SC_HR2 (E)
The mean hardness ratio of the bands 2 and 3 of all the detections of the source SRCID (EP_HR2) weighted by the errors(EP_HR2_ERR).
SC_HR2_ERR (E)
Error on the weighted mean hardness ratio in SC_HR2 (see 2XMM UG, Sec. 3.2.4 for details).
SC_HR3 (E)
The mean hardness ratio of the bands 3 and 4 of all the detections of the source SRCID (EP_HR3) weighted by the errors(EP_HR3_ERR).
SC_HR3_ERR (E)
Error on the weighted mean hardness ratio in SC_HR3 (see 2XMM UG, Sec. 3.2.4 for details).
SC_HR4 (E)
The mean hardness ratio of the bands 4 and 5 of all the detections of the source SRCID (EP_HR4) weighted by the errors(EP_HR4_ERR).
SC_HR4_ERR (E)
Error on the weighted mean hardness ratio in SC_HR4 (see 2XMM UG, Sec. 3.2.4 for details).
SC_DET_ML (E)
The total band detection likelihood of the source SRCID is the maximum of the likelihoods of all detections of this source (EP_8_DET_ML).
SC_EXTENT (E)
The total band extent (arcseconds) of the source SRCID is the weighted average of the EPIC extents of all detections of this source (EP_EXTENT).

This column is new in 2XMMi-DR3.

SC_EXT_ML (E)
The total band detection likelihood of the extended source SRCID is the largest of the extent likelihoods of all detections of this source (EP_EXTENT_ML).

In 2XMMi-DR3, the definition of this column is changed from that in 2XMMi (in 2XMMi, it was the average of the EP_EXTENT_ML values).

SC_CHI2PROB (E)
The χ2 probability (based on the null hypothesis) that the unique source SRCID as detected by any of the observations is constant, that is, the minimum value of the EPIC probabilities in each detection, EP_CHI2PROB, is given.
SC_VAR_FLAG (L)
The variability flag for the unique source SRCID is set to VAR_FLAG of the most variable detection of this source.
SC_SUM_FLAG (J)
The summary flag for the unique source SRCID is taken to be the worst flag of all detections of this source (SUM_FLAG).
N_DETECTIONS (J)
The number of detections of the unique source SRCID used to derive the combined values.
SC_DR_FIRST (J)
This flag indicates in which catalogue in the 2XMM catalogue series (starting from 2XMM) this unique source first appeared. The flag is DR1 for 2XMM, DR2 for 2XMMi and DR3 for the present 2XMMi-DR3 catalogue.

This column is new in 2XMMi-DR3.

SC_DR_LAST (J)
This flag indicates in which catalogue in the 2XMM catalogue series (starting from 2XMM) the parameters of this unique source were last updated (e.g. due to the inclusion of one or more new detections which can add to, or even split, the source). The flag is DR1 for 2XMM, DR2 for 2XMMi and DR3 for the present 2XMMi-DR3 catalogue (see Sec.3.2

This column is new in 2XMMi-DR3.

CONFUSED (J)
This flag (True/False) signifies that the 3-sigma error circle of a detection within this unique source overlaps the 3-sigma error circle of a nearby unique source. As such, it is an indicator of possible confusion (uncertainty) about the assignment of detections between sources.

This column is new in 2XMMi-DR3.

Two columns, SC_CHFLAG1 and SC_CHFLAG2, present in 2XMMi, are dropped from 2XMMi-DR3, being replaced by SC_DR_FIRST and SC_DR_LAST which have a simpler interpretation