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Slews: Fast and Slow


Fast Slew Status
XMMSL1: catalogue of slew sources released May 2006
Revs 314-978, 5180 detections, 2692 clean sources, 259 hard (2-10 keV) sources, 6200 square degrees, attitude error=8" (1 sigma) Read et al, 2006, PASJ - Scientific highlights Esquej et al, 2007, A&A ­ High variability galaxies Saxton et al, 2007, A&A (in prep) ­ Full description


SOFT 0.2-2 keV

HARD 2-12 keV



Fast Slew: work in progress
XMMSL1/delta-1 to be released May/June
Revs 1200-1309, 110 slews, 3800 deg^2, 3850 detections. Still needs to be cleaned. Total of 10,000 deg^2; about 4000 clean sources.


XMMSL1 + Delta-1

Exposure Map


Fast Slew: work in progress
XMMSL1/delta-1 to be released May/June
Revs 1200-1309, 110 slews, 3800 deg^2, 3850 detections. Still needs to be cleaned. Total of 10,000 deg^2; about 4000 clean sources.

6000 deg^2 of useful slews still to process, further deltas planned to be released every few months.


Fast Slew: fast turn-around Variability analysis
o Retrieve SDF from XSA ­ 10-20 days after observation o Initial processing to event file ­ 1 day o Split into discrete images ­ 1 day o Source search ­ 1 day o Calculate RASS upper limits, cross-correlate with NED, SIMBAD ­ 1 day

Can find high variability slew sources 14-24 days after slew in time for follow-up


XMMSL1 J060636.2-694932

SWIFT

Rev 1210 @ F5ts /to Nh=0.xE20ghtBr tDan 6 eV S upper limit 2 i c s; >203 2 bri , B e O h =6 RAS Probably Alsoosea n nneRge of2L6 @ 4.0yc/ical T=20-80 eV a N v e o i d ev 1 4 MC ­ t ps Piled-up, no offset map but can do rough spectral work with slew data


XMMSL1 J060636.2-694932

SWIFT

SWIFT UVOT B and UVW2


Slow Slew

http://...

Available as link from SOC external web


Slow Slew Test
Scan over the Galactic plane at 30 degs/hour Orbit 1242 - 16 legs covering 45 x ~0.5 degs with 15 arcmin overlap between legs ~200 deg^2 Open loop slew for 1.5 hours, followed by closedloop slew of 17 mins to set position to start of next leg. Operationally went very well Drift was very small, typical offset was 2 arc mins. will increase if slew rate decreases


Properties
Mean background (c/arcmin2) from slew legs 5,7: INST 0.2-12 0.2-2 2-12 ----------------------------------------PN 0.56 0.28 0.28 M1 0.10 0.062 0.041 M2 0.11 0.067 0.066 But extraction region bigger for MOS because of extension in slew direction (1.5x depending on final frame time)

Flux Limits INST 0.2-12 0.2-2 2-12 ------------------------------------------------------PN 5x10-13 2.5x10-13 1.6x10-12 PN+MOS1/2 4x10-13 2x10-13 1.3x10-12

3x deeper than XMMSL1

PN: Exposure time ~6x normal slew, limits MOS ~3x lower eff. Area (depending on spectrum, etc.) but 2-3x lower backgnd. MOS 3x3 Pattern 0 = Singles + 2/3 doubles + 4/9 (trips+quads) + Part of Patt 31 Q.E. to be calibrated....


Any advance possible?
Slew speed down to 20 deg/hr certainly possible. Even 10 deg/hr may be achievable without losing too much positional accuracy. In which case: Flux Limits at 10 deg/hr INST 0.2-12 0.2-2 2-12 ------------------------------------------------------PN+MOS1/2 2.5x10-13 1x10-13 8x10-13

Remains to be tested


Slow Slew Summary
PN ­ to run in FF mode, Medium filter MOS ­ intended to run in 3x3 pixel free running mode with ~400ms frame time. Work to do with s/w (nearly complete), calibration and CCFs ­ particularly MOS QE / pattern fractions For efficiency need to have legs of at least 1 hour as turn-around time is 17 mins. Great for mapping large extended sources Probe flux levels intermediate between XMMSL1 and dedicated short pointings, 10-13 Position error is ~4 arcsecs ­ similar to pointed obs for
low count sources


Simulations/Spurious fraction
Find dependence of spurious sources on number of photons in image Randomise the position of every photon in all 11400 slew images and run the standard source search Tabulate number of false sources Real sources and fluctuations for different selections