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Prospects for Swift studies on NS X-ray binaries (sorry, no magnetars). Sergio Campana Osservatorio astronomico di Brera. UVOT. BAT. BAT. XRT. UVOT. XRT. Spacecraft. Spacecraft. Swift Mission (Nov. 2004 - ...). Burst Alert Telescope (BAT) CdZnTe detectors (7 keV energy resolution)
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Prospects for Swift studies on NS X-ray binaries (sorry, no magnetars) Sergio Campana Osservatorio astronomico di Brera Cairo March 2009
UVOT BAT BAT XRT UVOT XRT Spacecraft Spacecraft Swift Mission (Nov. 2004 - ...) • Burst Alert Telescope (BAT) • CdZnTe detectors (7 keV energy resolution) • 15-150 keV • 1-4’ localization over 2 sr field of view • X-Ray Telescope (XRT) • CCD (140 eV @ 6 keV) • 0.3-10 keV • <5” localization over 24’x24’ • (UVOT) UV/Optical Telescope • Imaging & Grism spectroscopy • UV to V • Sub-arc localization • Autonomous re-pointing, 60 - 300 sec • Onboard and ground triggers
Swift strenghts (I) Multi-wavelength coverage XRT UVOT Falanga et al. 2007 SWIFT J1922.7-1716 BAT INTEGRAL XRT RXTE GRO J1655-40 Brocksopp et al. 2006
Swift’s strengths (II) BAT monitoring of the X-ray sky (about 100 sources detected daily). BAT is able to discover new X-ray transient and follow them during the brightest part of the outburst. Daily 1 ks observation of the Galactic Center. Galactic Center region Krimm et al. 2006 1600 s
Swift’s strengths (III) Thanks to its scheduling flexibility (one shot) ideal instrument to perform short exposures to identify and to provide an accurate localization of hard X-ray sources (e.g. INTEGRAL, RXTE, Swift-BAT) as well as past and present X-ray missions (RASS, ASCA and XMMSL). IGR J08408-4503 IGR J18483-0311 Sguera et al. 2007 INTEGRAL ROSAT Swift-XRT ISGRI, JEM-X Swift-XRT Leyder et al. 2007
Swift’s strengths (IV) Thanks to its scheduling flexibility (multiple shots) ideal instrument to perform (loose) monitoring campaigns. 23 d RXS J171824.2-402934 Campana 2009
Strange transients 10 d Wijnands et al. 2009 Consistent with a type I burst from a LMXRB
Accreting ms X-ray pulsars Discovery of the seventh AMXPs SWIFT 1756.9-2508 Krimm et al. 2008
X-ray transients (AMXP) SAX J1808.4-3658 Campana et al. 2008
X-ray transients (classical) EXO 0748-676 Degenaar et al. 2009 unpublished Aql X-1
Monitoring of the Galactic center Degenaar & Wijnands 2009
Fast transients IGR J11215-5952 Romano et al. 2007 P~164.6d Eccentric orbit Romano et al. 2008 INTEGRAL
Fast transients (II) Sidoli et al. 2008
Summary • Swift thanks to: • Wide energy range UV to hard X • Flexibility • Sensitivity (especially for binaries and AXP that are bright objects) • Can in the next few years provide important results in this field • Detecting (new/rare transient sources, bursts, superbursts) • Monitoring (evolution of outbursts, long term spectral changes, timing) • Archiving (long term light curves)
Swift in perspective • Monitor X-ray binary transients’ state changes, launch of micro-jet and jets (BAT, XRT, UVOT) • X-ray burst statistics (BAT) • Detect in real time and follow superbursts (BAT & XRT follow-up) • Follow fast transient outbursts (XRT) • Follow transient outbursts down to quiescence (BAT, XRT & UVOT)
X-ray burst studies & statistics Cornelisse et al. 2003 Cocchi et al. 2001 Burst rate as a function of flux Galloway et al. 2004 Eddington-limited burst Periodic behaviour as a function of flux
Superbursts In’t Zand et al. 2004 4U 1636-53 Strohmayer & Markwardt 2002
State transitions BH XRB Belloni 2007 NS XRB Homan et al. 2007
X-ray transients 2002 2006 mCrab Aql X-1 SAX J1808.4-3658 Campana et al. 1998 Campana et al. 2007a