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X-ray Astronomy in the Near Future. Some Thoughts. Victoria Kaspi (McGill University) Weizmann Institute, June 7, 2010. X-ray Targets. accreting neutron stars, white dwarfs microquasars & accreting black holes Rotation-powered pulsars, cooling NSs Magnetars AGN Galaxy clusters
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X-ray Astronomy in the Near Future Some Thoughts Victoria Kaspi (McGill University) Weizmann Institute, June 7, 2010
X-ray Targets • accreting neutron stars, white dwarfs • microquasars & accreting black holes • Rotation-powered pulsars, cooling NSs • Magnetars • AGN • Galaxy clusters • supernova remnants • Supernovae • Gamma-ray bursts
XTE J1810-197 X-ray Observables Images Spectra Timing Monitoring
Current X-ray Missions NASA Chandra ESA XMM-Newton NASA RXTE ESA INTEGRAL JAXA/NASA Suzaku NASA Swift JAXA/MAXI
Upcoming Missions ASTROSAT (>2011) NuSTAR 2012 eROSITA 2012 Astro-H 2014 GEMS 2014 HMXT 20?? (China) IXO 2021?? EXIST, WFXT, AXTAR: proposed...
MAXI on ISS JAXA/ISS 3 0.5-30 keV X-ray slit cameras scan entire sky every 96 mins though only 1-2% of sky visible at any time PSF 1.5 deg, posndet ~6amin 5sigma 10 mCrab (1 orbit), 1 mCrab (1 week) Not better than ASM...
ASTROSAT • Launch >2011, ISRO w/CSA • 5 instruments: UVIT, LAXPC, SXT, SSM, CzTl • UVIT: 130-180nm, 180-300nm, 320-530nm, twin FOV 28’ diameter circle, ang res 1.8” UV, 2.5” visible channel, 50cm2 eff area, 10 ms time res, 21stmag (5sigma) in 1800s • For UV channels, grating can be used, sliltless spectroscopy w/res ~100 • SXT: 0.3-8keV, like Swift XRT, CCD focusing 3-4’ HPD, 0.35 deg FOV, 200 cm2 @ 1 keV 10 uCrab (5sig) in 10ks • LAXPC: PCA clone 3-80 keV, 3 PCs, 1degx1deg, 6000 cm2 @ 10 keV, 10 us timing, 0.1 mCrab (3sig) in 1ks • CZTl:CDZnTl ~1000cm2 geom area, 10-150 keV, 10 deg FOV up to 100 keV, 2% res @ 60 keV, 2D coded mask • SSM: 3 PCs w/1-d coded mask, like ASM
NuSTAR SMEX; First focusing of hard X-rays; 10m deployable CdZnTe pixel detectors; multi-layer coated segmented mirros in Wolter I like config 5-80 keV, ang res 43” HPC, 7.5” FWHM 13’x13’ FOV but e-dependent; 3’x3’ @ 60 keV Eres 1.2 keV @ 68 keV; tres 0.1 ms ~100x pt src sensitivity of INTEGRAL
eRosita Extended Roentgen Survey with an Imaging Telescope Array Primary instrument on Spectrum-Roentgen-Gamma (SRG) Launch 2012 from Baikonur/Soyuz 2 into L2 orbit Imaging all-sky survey 6-30 keV, will last ~4 yr 7 Wolter I modules, CdTe Effective area 1500 cm2 @ 1.5 keV On-axis PSF HEW 15”, FOV ~0.8 deg2 See Predehl et al. arXiv:1001.2502 Science: detect 50k-100k galaxy clusters to z~1.3 for LSS; complements SPT
Astro-H (ISAS/JAXA/NASA)arXiv:0.807.2007v1; PI Takahashi Launch planned 2014, 550 km 96 min 4 instruments: HXI, SXS, SXI, SGD HXI: 2 HXTs 5-80keV, 12m focal length; 300cm2@30keV; 1.9’ (HPD); 9’x9’ FOV SXS: 210cm2@6keV, 6m focal, 0.3-10 keV w/7eV energy resolution, 2.85’ FOV on side, 1.7’ (HPD)at 6keV 60% higher eff area than Suzaku, about same at 1keV SXI: 35’x35’, CCDs, 6-m focal length, 1.7’ (HPD), eres 150 eV@6keV; 360 cm2 @ 6keV SGD: non-focussing, 10-600 keV, 10x more eff area than Suzaku HXD at 300 keV; 2 keV @ 40 keV; 0.55x0.55 deg2 FOV Possible Canadian Space Agency involvement: metrology system
GEMS (SMEX, PI Swank) Gravity and Extreme Magnetism SMEX Launch 2014; 2 yrs; Core: 35 srcs in 9 mos 2-10 keV; 3 foil mirrors (4.5m focal length) w/e- scattering detectors; eff area 510cm2@6keV; 12’ FOV; PSF 1.5’ Spacecraft rotates 0.1 rpm to mitigate systematics MDP 1% for 20 mCrab in 100 ks; Detector: small gas chamber; X-ray absorbed, e- emitted starting in dir related to polarization. Measure dir of ionization track as e- moves Contrasts w/scattering polarimeter which doesn’t focus
Energy Dependent XPOL: Scientific Motivation • For compact objects imaging generally useless as source too small • Exceptions pulsar wind nebulae, microquasars, AGN • Compact objects generally studied via: • Spectroscopy • Timing • X-ray polarimetry adds: • Polarization fraction • Polarization position angle
IXO (ESA, NASA, JAXA) 3m2@1.25keV, 0.65m2@6keV; 0.015m2@30keV 20 m focal length, 800,000 km around L2 Atlas V or Ariane 5 launch, 2021?? 6 instruments under study:XMS, XGS, WFI, HXI, HRTS, XPOL
How Phase Space Being Covered? • Improved imaging, ang res < 1” • <10 keV: CXO; >10 keV ??? • High throughput below 10 keV • Focusing: IXO; Not focusing: AXTAR • Wide Field Surveys: • Soft: eROSITA; Hard: WFXT, EXIST; Harder: ACT • High-res spectrscopy: Astro-H, IXO • Hard X-ray imaging: NuSTAR, Astro-H • Multiwavelength: Astrosat • Monitor: ASM, MAXI, SSM
What Can be Done? • Wide-field hard X-ray imaging • X-ray Polarimetry • Sensitive all-sky monitoring
Argos-X (2008 SMEX unfunded proposal; PI Remillard MIT) 3pi sr instantaneous sky coverage by 25 2D coded-mask cameras w/pixelated Si detectors (NRL) 50% avg live-time of any point in sky 1.5-28 keV, 600 eV resolution; 122 us time res 1-2 amin positions 1 mCrab (4sig) for known sources in 1 day (10x better than ASM/SSM/MAXI)
V. Kaspi, D. Hanna; McGill U. X-ACTX-ray Astronomy Canadian Telescope THE MISSION: X-ray polarimeter (XPOL), all-sky monitor (ASM) THE TARGETS: black holes, AGN, neutron stars, magnetars, supernova remnants, plerions, blazars, gamma ray bursts, … THE REASON: promise of major breakthroughs in compact object physics from XPOL; ASM, crucial for monitoring the volatile high-energy sky, included for small extra cost THE OPPORTUNITY: XPOL neglected over past 30 yr; virginterritory of which Canada could become leader. Good ASMcrucial to success of GLAST, VERITAS, HESS,… WHY CANADA: World-class, young, active compact object, SNR, TeV, GR research community in Canada. Small satellite nichepossible; good match for Canadian industry.
Predicted polarization fractions and position angles as a function of energy for disk models near a spinning black hole. Disk with 75.5° inclination (Conners, Piran and Stark,1980)
Amplitude Amplitude Model predictions of accreting neutron star polarization properties for different viewing geometries at different energies. Polarization Fraction Polarization Angle Meszaros et al. 1988
Addressing Concerns • Maybe nothing will be polarized. • If nothing polarized at few % level, would be revolutionary… • If we don’t look, we’ll never know. • A non-detection will teach us nothing. • Non-detections at few % level for many sources will be shocking…back to model drawing board • All future models will have to satisfy constraints • Physics of polarimetry complicated. • If we build it, theorists will come. • Spectroscopy is easy? Yet we want Con-X, XEUS… New observational phase space carrying unique information with potential for high impact!