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Field content and target identification
Ann-Marie StobbartAnja Schroeder, Mike Watson and the XMM-Newton Survey Science Centre
20th Survey Science Centre Consortium meeting
14th November 2006 Ann-Marie Stobbart
2XMMp: selecting observations 2XMMp contains a subset of the total
number of observations to be included in the final 2XMM catalogue.
Subset selected via visual screening of each observation + sources + automatic flags
Quick field identifications based on the number of ‘spurious’ detections i.e. those NOT automatically flagged as spurious
14th November 2006 Ann-Marie Stobbart
2XMMp: selecting observations Observations classified into one of
four quality flags (OBSFLAG=0-3)
‘Good’ observations (OBSFLAG=0-2) included i.e. those with no or few obvious
spurious detections (83% public observations with EPIC data)
14th November 2006 Ann-Marie Stobbart
Observation classes: OBSFLAG=0
52% : no obvious spurious detections (may include one or two non-obvious ones)
14th November 2006 Ann-Marie Stobbart
Observation classes: OBSFLAG=1
30% : one or more spurious detections (but usually < 8 )
14th November 2006 Ann-Marie Stobbart
Observation classes: OBSFLAG=2
0.9% : class 1 + missed detections in a group of very densely positioned sources
14th November 2006 Ann-Marie Stobbart
Observation classes: OBSFLAG=3
17% : not accepted for inclusion in the catalogue
14th November 2006 Ann-Marie Stobbart
Field identification
2XMMp screening effectively independent of target itself
2XMM Serendipitous catalogue Aim for 2XMM is to classify XMM-Newton fields by the
type of target within them
But, is the target: a single object ? a whole field ? extended ?
14th November 2006 Ann-Marie Stobbart
Field identification
5 proposed field classifications:
Point source
Extended source Small extended Large extended
Field (e.g. The Lockman Hole)
Not detected (e.g. OM calibration field)
Unknown
14th November 2006 Ann-Marie Stobbart
Field ID : Large extended
NGC 55 (WEST): 0028740101 : X-ray background and surveys
SIMBAD
PROPOSAL
NED
RA_PNT
DEC_PNT
XSA
14th November 2006 Ann-Marie Stobbart
Field ID : Large extended
NGC 4258: 0059140401 : AGN, QSOs, BL-Lacs and XRB
SIMBAD
PROPOSAL
NED
RA_PNT
DEC_PNT
XSA
14th November 2006 Ann-Marie Stobbart
Target identification
Aim to flag the target of the observation
Difficulties, e.g. for galaxies no source to flag unambiguously
Simplest solution flag the targets from the ‘point source’ field classification
14th November 2006 Ann-Marie Stobbart
Summary
2XMMp screening: quick field identifications 83% public observations included
Aim for 2XMM: field and target identifications work in progress
Difficulties: Finding a position that best identifies the target in
order to classify the field finding an unambiguous target position in order to flag
the target