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Highlights from the XMM-Newton Slew Survey First Catalogue. Andy Read (University of Leicester) Richard Saxton (ESAC) M. Pilar Esquej (MPE/ESAC) [Poster A.13] Michael Freyberg (MPE) Bruno Altieri (ESAC). Average slew length is ~70 degrees
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Highlights from the XMM-Newton Slew Survey First Catalogue Andy Read (University of Leicester) Richard Saxton (ESAC) M. Pilar Esquej (MPE/ESAC) [Poster A.13] Michael Freyberg (MPE) Bruno Altieri (ESAC)
Average slew length is ~70 degrees Slew speed = 90 degrees / hour, i.e. on-source time <~14 secs (average ~10 secs!). Tangential projection not valid over whole slew. Long slews need to be subdivided to maintain astrometry. Divide slew into 1 deg2 images and recalculate sky positions. • Source search using near-standard pipeline tuned for ~zero background.
Initial Analysis MOS PN Extra pn sensitivity + additional MOS background means little to be gained from analysing MOS slews at present Source extended into a 4 arcmin streak due to 2.6 second frame time Full frame (73ms) mode streak = 6 arcsecs – not a problem - MOS slews used for calibration - All PN slews (FF, eFF, LW) larger than 15 minutes down-linked and processed - Processing details in Pili’s poster [A.13]
The XMMSL1 Catalogue ~6250 deg2 (15% of sky) Release April 2006 Full catalogue threshold: DET_ML>8 * Clean catalogue threshold: DET_ML>14 + (DET_ML>10 + BG_RATE<3) Full hard band catalogue contaminated at a level >10% (spurious sources) Full soft band catalogue contaminated at only ~7%
Survey Characteristics Source Count Distribution Exposure Time Distribution 4200 cts - Can calculate flux limits for the XMM-Slew survey
Survey Characteristics – Soft Band XMM-Slew 10-13 10-14 0.5-2 keV flux limit (erg cm-2 s-1) 10-15 10-16 10-17
Survey Characteristics – Hard Band 10-10 Exosat HEAO-1 RXTE (only 1 deg pos.accuracy) 10-11 EMSS 2-10 keV flux limit (erg cm-2 s-1) (only <4keV) XMM-Slew 10-12 10-13 10-14
Identifications Cross-correlation of source list with Simbad, NED, HEASARC, RASS etc. Counterparts found for >50% of sources. AGN: 425 Galaxies: 467 Clusters : 72 Variable stars: 62 SNR: 14 LMXB: 8 HMXB: 5 WD: 2 HB89 0642+449 (QSO) z=3.4 (1.2 ct/s)
Hardness Ratios Galactic Latitude (deg) • LMXRBs (hardest sources) congregating in Galactic plane • Very few soft sources in the Galactic plane (none extragalactic)
RA-Dec Distribution RASS IDs Mean positional error ~8” Random positions
Extremely Bright Sources Galactic Plane RX J173143.6-165736 LMXRB 2600 cts in 8 sec
Sources Detected in Multi-Slews • Source detected in 3 separate slews: Rev 570 Rev 573 Rev 574 • Evidence for variability (factor ~2) 105 sources seen in more than one slew
Correlations with ROSAT • - 55% of sources correlate with ROSAT (non-extended, DET_ML>10) - 1% show variability by > factor of ten Mean rate : XMM-slew/ROSAT=10 XMM slew upper limits to be calculated
DSS Image 2’×2’ Total band (0.2-12 keV) Soft band (0.2-2 keV) Hard band (2-12 keV) Variable star UY Vir : Slew/RASS count rate ratio=240
(D~30Mpc?) (D~12Mpc) Very soft ! Lx ~ 3x1041 erg s-1 ! Lx ~ 2x1042 erg s-1 !? NGC 3599 – Slew/RASS count rate ratio ~500! (RASS upper limit <2x1039 erg s-1)
Extended sources • Associations with 81 Zwicky/Abell clusters 15% of sources extended Extension BG-subtracted counts (0.2-12 keV)
Galaxy Clusters XMM-Slew Sensitive to relatively faint clusters and extended sources in general thanks to wide band-pass, tight PSF and low background.
Supernova Remnants Puppis A ROSAT HRI XMM slew Red: softBlue: hard Also a cause of ‘spurious’ sources
Vela Supernova Remnant Contours of XMM-slew emission (~8 secs exposure)
Vela Supernova Remnant ROSAT XMM-Newton Slew ~½ hour observing time !
Completeness * Including high background slews - Upgrade catalogue using high-background slews, other remaining problematic slews and new slews as they become available
Concluding Remarks • Catalogue (full and clean) public in ~1 week or so - accessible via XMM XSA (also as FITS files) • Soft band survey comparable with RASS • Hard band survey best ever • ~0.65 sources per square degree over ~15% of the sky • ~50% of the sources have identifications • Many high-redshift detections • Extremely interesting ROSAT-XMM variability – Rare events! • Excellent extended source detection and large area mapping capabilities • To come: - Upper-limits server for slew images as part of XSA - Processing of high-BG and problem slews and new slews - Whole sky covered in ~few years time, even using present slew operational mode
Spurious Detections:2. High Background: Indistinguishable from extended source. 30s flare = 45’ diameter “remnant”.
Spurious Detections:3. Optical loadingOnly important for the very brightest stars XMM-Slew counts (0.2-2 keV) USNO R1 magnitude pn ccd#9 pn ccd#6 The very bright star Sirius moving across the pn detector
SNRs in the SMC Raw slew image
Mrk 352 ESO443-IG005 MCG 04-53-021 NGC5899 Four Galaxies Non-RASS
Two Merging Galaxy Pairs NGC 4748 II Zw 742
Well Known Sources N132D (4.1″ pixels)
… and other oddities… Southern source - RASS Northern source – non-RASS
Optical loading Sirius Sgr X-3 Only important for the very brightest Stars.
LII-BII Distribution RASS IDs
Extremely Bright Sources LMXRB 4200 cts in 8 sec
QQ Vul CV QQ Vul (AM Her-type) Slew/RASS count rate ratio=0.38 - Very soft!
Status summary - Finished processing for 15% of sky (revs 314-980) - 5200 (3300) sources detected in total, soft and/or hard band with det_ml>8 (10) - 845 in hard band (426) - Significant number of spurious detections (see later) - Some overlap: 105 sources seen in more than one slew - Mean positional error ~8” - Plan to release catalogue, via the XSA (v2.9) and as FITS file at end of Feb or March. Total band: 0.2-12 keV Soft band: 0.2-2 keV Hard band: 2-12 keV
Overview - 390 slew datasets in archive - PN, MOS-1/2 exposures in Medium filter with the observing mode set to that of previous pointed observation - Average slew length is ~70 degrees - Closed slew, open slew, closed slew. Open slew speed = 90 degrees / hour, i.e. on-source time <~14 secs (average ~10 secs!) - Area covered to date ~8000 deg2 (~20% of sky)
Status summary - Finished processing for 15% of sky (revs 314-980) - 5200 (3300) sources detected in total, soft and/or hard band with det_ml>8 (10) - 845 in hard band (426) - Significant number of spurious detections (see later) - Some overlap: 105 sources seen in more than one slew - Mean positional error ~8” - Plan to release catalogue, via the XSA (v2.9) and as FITS file at end of Feb or March. Total band: 0.2-12 keV Soft band: 0.2-2 keV Hard band: 2-12 keV