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