Update on the XMM Slew Survey Richard Saxton 1, M. Pilar Esquej 1 Andy Read 2, Michael Freyberg 3, Bruno Altieri 1, 1 ESAC 2 University of Leicester, U.K. 3 MPE, Garching, Germany 3

Status summary o Finished processing for 15% of sky (revs ) o 5200 (3300) sources detected in total, soft and/or hard band with det_ml>8 (10) o 845 in hard band (426) o Significant number of spurious detections (see later) o Some overlap: 105 sources seen in more than one slew o Mean positional error ~8” o Plan to release catalogue, via the XSA (v2.9) and as FITS file at end of Feb or March. Outstanding Work: Identification of counterparts Removal/assessment of spurious sources

Identifications Cross-correlated source list with Simbad, NED, HEASARC. Also working with the GAVO cross-matching tool to find the most likely optical/2MASS/radio counterparts. Found counterparts for 55% of sources. Represented categories: AGN: 500 Galaxies: 750 Clusters/groups : 80 Active stars: 80 SNR: 12 LMXB: 16 HMXB: 3 WD: 2 HB (Z=3.4)

Correlations with ROSAT  55% of sources correlate with ROSAT (non-extended, DET_ML>10)  1% show variability by > factor of ten Mean rate XMM/ROSAT =10

Spurious detections Extended source: mainly due to SNR Halo of bright source: mainly LMXB High Background: indistinguishable from extended source, 30s flare = 45’ diameter “remnant”. Optical loading:

Large/Bright Extended Sources XMM slewROSAT HRI Sources found in Puppis-A

Bright source

High background Many sources due to background flare

Optical loading Only important for the very brightest Stars. Sirius

Optical loading Only important for the very brightest Stars. SiriusSgr X-3

Hard sources  After removing spurious sources due to the effects mentioned before, we are left with 707 hard sources but expect only ~ from previous ln-n/ln-s work.  Hints that sources may be related to background level

Hard sources  After removing spurious sources due to the effects mentioned before, we are left with 707 hard sources but expect only ~ from previous ln-n/ln-s work.  Hints that sources may be related to background level

Extended sources 15% of sources extended Associations with 81 zwicky/Abell clusters

Galaxy Clusters Sensitive to relatively faint clusters thanks to wide band-pass and low background.

Gallery of famous clusters

A 2029

Also famous SNR VELA

Conclusions  Expect to make catalogue public in 1-2 months  Battling with spurious sources. How many ?, which ones ?, where to cut in parameter space ?  Making progress with identifications  Many high-z detections  Interesting Rosat/XMM variability  Potentially interesting extended sources  Project starting this year to provide an upper- limits server for slew images as part of XSA

Survey Characteristics Source Count DistributionExposure Time Distribution 4 ~ 10 seconds - Can calculate flux limits for the XMM-Slew survey

RASS 5.0x (92% of sky) EMSS 3.0x (2% 0f sky) HEAO-1 3.6x (all-sky) Exosat 5.0x (?% of sky) RXTE 1.0x (all-sky), but with only 1 ° positional accuracy Flux limits

Extremely Bright Sources Several LMXB at few hundred c/s

Detector problems Affects one CCD so must be detector related Often appear as non-single events Very soft spectrum with a peak at 100 eVEvents occur within 1 frame Detector map shows events Confined to 1 CCD.

Spurious Sources… … due to crab off-axis !Sources 1 & 3 of Pilot#1